Volume 168 Issue 4

Surgery for primary hyperparathyroidism 1962-1996: indications and outcomes Leigh W Delbridge, Nidal A Younes, Ana I Guinea, Thomas S Reeve, Phillip Clifton-Bligh and Bruce G Robinson MJA 1998; 168: 153-156 For editorial comment see Edis Abstract - Introduction - Methods - Results - Discussion - Acknowledgements - References - Authors' details - - ©MJA1998 Abstract Objective: To examine changes over the past three decades in the indications for, and outcomes of, surgery for primary hyperparathyroidism. Design: Survey of a prospective hospital database. Setting: Royal North Shore Hospital (a tertiary referral and university teaching hospital), Sydney, New South Wales, January 1962 to December 1996. Patients: All 733 patients who underwent neck exploration for primary hyperparathyroidism. Results: The annual number of parathyroidectomies increased virtually exponentially, from a mean of two in 1962-1969 to 73 in 1996. In the 1960s and 1970s, the most common indication for surgery was the presence of renal calculi (58% and 43%, respectively), but in the 1980s there was a marked increase in presentation of asymptomatic disease after biochemical screening (19%). In the 1990s, low bone mineral density detected by osteodensitometry has become the most common indication for surgery (31%). After initial operation, 11 patients (2%) had persistent hypercalcaemia, with five of these cured by reoperation -- an overall failure rate of 1%. Conclusions: Surgery for primary hyperparathyroidism has become increasingly common, with low bone mineral density replacing renal calculi as the most common indication for surgery. Neck exploration in experienced hands results in an overall cure rate of 99%. Introduction The past few decades have seen dramatic changes in the apparent incidence, presentation and management of primary hyperparathyroidism. With advances such as ready access to serum calcium and parathyroid hormone measurements, the condition is being increasingly recognised and treated, and new patterns of presentation are being seen. The classic bone disease osteitis fibrosa cystica, the principal manifestation early this century, is now rare.1 A clinical picture has emerged characterised either by an absence of symptoms or by subtle and vague symptoms,2-4 such as fatigue, weakness, and variable aches and pains, with the condition often suspected only because of an incidental finding of an elevated serum calcium level on biochemical testing. The recent introduction of bone mineral density screening by osteodensitometry seems also to have increased detection of cases of primary hyperparathyroidism.5 Our aim was to examine the changes over the past three decades in presentation and management of primary hyperparathyroidism at a single large referral centre, and to analyse the indications for, and outcomes of, surgery for this condition. Methods Subjects were all patients who underwent surgery for primary hyperparathyroidism in the Endocrine Surgical Unit at Royal North Shore Hospital, Sydney, New South Wales, from January 1962 (date of the first parathyroidectomy at the unit) until December 1996. Information was obtained from the prospective database of all endocrine surgical procedures maintained at that hospital since January 1957. The database was searched for any follow-up to December 1997. The diagnosis of primary hyperparathyroidism was based on the finding of an elevated serum calcium concentration and, when available, an inappropriately normal or elevated parathyroid hormone concentration. Before 1972, parathyroid hormone assays were not available, and the diagnosis was based on a combination of biochemical, radiological and clinical changes (eg, renal stones, urinary tract infection, abdominal pain and neuropsychological disturbances). Patients with secondary or tertiary hyperparathyroidism were excluded from the study. Information was obtained on the presentation, indications for surgery, operative details, postoperative complications, histopathological results and surgical outcomes. Persistent hyperparathyroidism was defined as hyper calcaemia continuing after surgery. Recurrent hyperparathyroidism was defined as hypercalcaemia returning after a minimum of six months of postoperative normocalcaemia. Results Between January 1962 and December 1996, 733 patients underwent neck exploration for primary hyperparathyroidism at Royal North Shore Hospital. They comprised 161 males (22%) and 572 females (78%), with an age range of 9-96 years (median age, 53 years for males and 60 years for females). Annual numbers of operations for primary hyperparathyroidism are shown in Figure 1. The number has risen virtually exponentially, from one to four annually in the 1960s, to 73 in 1996. Indications for surgery: These are shown in Box 1. The presence of renal calculi was the principal indication for surgery between 1962 and 1969, accounting for 58% of operations, but has progressively decreased in importance, accounting for only 15% of operations between 1990 and 1996. Numbers of asymptomatic patients (in whom none of the recognised symptoms of primary hyperparathyroidism could be identified preoperatively) increased in the 1970s and 1980s, but remained low overall (105 patients, 14%). Between 1990 and 1996, the most marked change was the increase in patients with low bone mineral density detected on screening for osteoporosis (by osteodensitometry or quantitative computed tomography) as the principal indication for surgery. In the 1990s, it was the most common indication (31% of cases), followed by neuromuscular or neuropsychiatric symptoms (20%) and renal calculi (15%), with only 14% of cases considered truly asymptomatic. Surgical and pathological findings: At surgery, single-gland disease (presence of only one enlarged gland) was found in 556 patients (76%), two-gland disease in 40 (5%), three-gland disease in two (0.3%), four-or-more-gland disease in 121 (17%), carcinoma in two (0.3%), cyst in seven (1%), and no parathyroid abnormality in five (0.7%). Complications of surgery: Postoperative hypocalcaemia requiring calcium supplementation was seen in 81 patients (11%), but only two of these had permanent hypoparathyroidism. Eight patients developed a wound infection (1%), eight required reoperation for haemorrhage (1%), six had a permanent vocal cord palsy (1%), and one required a temporary tracheostomy because of intraoral haemorrhage caused by injury to the tongue. One patient with pre-existing ischaemic heart disease died in the immediate postoperative period. Outcomes of surgery: Hypercalcaemia was cured immediately in 716 of the 733 patients. In six of the remaining 17, initial neck exploration showed no abnormalities, and they were subsequently shown to have conditions other than hyperparathyroidism, for which surgery was not indicated: sarcoidosis (three), familial hypocalciuric hypercalcaemia (two), and persistent hypercalcaemia with no apparent cause (one). Eleven patients had persistent hypercalcaemia caused by primary hyperparathyroidism after initial surgery, giving an initial cure rate of 98%. Details of initial and subsequent surgery for these 11 are shown in Box 2. Five were cured by re-exploration of the neck, two remained hypercalcaemic after a further unsuccessful re-exploration, and four had not undergone further surgery (two refused and two were awaiting further assessment). Thus, the overall cure rate for surgery was 99%. Hypercalcaemia was known to have recurred in two patients, at a mean of 10.5 years after successful surgery. Recurrence was associated with multiple endocrine neoplasia Type 1 syndrome (MEN1) in one of these patients and was cured by removal of the remnant and autotransplantation. The second patient had mild asymptomatic hyperparathyroidism for which reoperation was not indicated. Discussion We found that, as expected, surgery for primary hyperparathyroidism became increasingly common at Royal North Shore Hospital over the past three decades. In the 1990s, low bone mineral density replaced renal calculi as the most common indication for surgery. Initial neck exploration resulted in cure in 98% of cases. Primary hyperparathyroidism occurs relatively frequently in the community, with an incidence of at least 1 in 1000 individuals,6 and may be as frequent as 1 in every 500 women over the age of 50 years.7 The very small numbers of patients being diagnosed and treated as recently as two decades ago related to lack of ready access to serum calcium and parathyroid hormone measurements, as well as lack of awareness of the disease. Surgery is indicated in patients with symptoms or a high serum calcium level, and in asymptomatic patients who are not suitable for conservative management.8 The commonest indication for surgery now is the presence of low bone mineral density (36% of operations in 1996). Recovery of bone mass has been documented after successful parathyroid surgery in many series, even in patients with mild or asymptomatic hyperparathyroidism.5 The presence of renal calculi remains a major indication for surgery. Although the percentage of patients undergoing neck exploration for this indication has declined significantly each decade, the actual numbers have, in fact, steadily increased. Renal calculus formation is reduced after successful parathyroid surgery,9 although preformed stones or those associated with idiopathic hypercalciuria may continue to be passed.10 Marked muscular atrophy is rarely seen nowadays, but muscular weakness contributing to a general feeling of tiredness and malaise is noticed in most patients with primary hyperparathyroidism.11 We found neuromuscular disease was the primary indication in 11% of our patients. Abnormalities included muscular atrophy, generalised weakness and fatigue, which are thought to be related to low plasma phosphate level and possibly hypokalaemia. Many patients with these symptoms have reported improvement after parathyroidectomy.12,13 Neuropsychiatric symptoms were the primary indication for surgery in only 9% of patients in this series, but may be found (if sought) in significant numbers of patients with primary hyperparathyroidism (reported incidence, 30%- 100%).14 Symptoms include depression, anxiety, fatigue, lassitude, concentration difficulties, and failing memory. They have been reported to improve or disappear in most patients after surgery.12,15 A recent study showed that the most dramatic changes are reductions in body pain and improvements in vitality and emotional function.16 Similarly, although abdominal symptoms (which may be related to peptic ulcer disease, pancreatitis or constipation) were the primary indication for surgery in only 5% of our patients, they may be seen in up to 20% of patients with primary hyperparathyroidism.17 In our series, 14% of patients appeared asymptomatic. The proportion of patients with primary hyperparathyroidism reported to be asymptomatic varies greatly, from 2% to 80%,3,17-19 possibly depending on the care with which they are evaluated. Indeed, vague psychiatric and neuromuscular symptoms and generalised weakness may be fully appreciated only in retrospect, once normocalcaemia has been achieved by surgery.20 It is important to consider surgery even in the asymptomatic, as there is increasing evidence that primary hyperparathyroidism affects longevity. Several studies have shown that untreated individuals with mild hypercalcaemia have a reduced survival rate.21 A study of 441 patients followed up for a mean of eight years showed that successful parathyroid surgery reduced the risk of dying,21 while a more recent study of 896 patients confirmed this result and showed that the duration of hyperparathyroidism is also a factor, with early surgery reducing the risk of dying.22 A National Institutes of Health consensus statement from 1990 addressing the management of asymptomatic primary hyperparathyroidism recommends that "all patients with primary hyperparathyroidism should be considered to be candidates for surgery".8 The aim of surgery in primary hyperparathyroidism is to identify and remove all abnormal parathyroid tissue. As multiple-gland disease is common (22% of patients in this series), the mainstay of good surgical technique is to identify all (four or more) parathyroid glands in order to differentiate normal from abnormal glands (see Figure 2). We believe that current passing interest in "minimal access" parathyroid surgery (endoscopic or unilateral minimal incisions based on preoperative localisation) is misguided. Such techniques should be avoided as they will inevitably increase failure rates from unsuspected multiple-gland disease for, at best, a very marginal cosmetic advantage. Localisation techniques such as ultrasonography, computed tomography and scintigraphy with sestamibi have not shown sufficient sensitivity and specificity to justify routine use before initial operation and are certainly not cost-effective.23,24 False positive and false negative results from preoperative localisation tests may add confusion, especially for the inexperienced surgeon. Indeed, surgery undertaken by those not experienced in the procedure has been shown to be associated with a high failure rate and need for reoperation, as well as increased complications.25 For example, a Scandinavian study showed that surgery performed in units doing fewer than 10 parathyroidectomies per year resulted in only 70% of patients achieving long-term normocalcaemia,25 whereas in experienced units a success rate of 98% should be achieved. Acknowledgements We wish to acknowledge the following additional physicians and endocrinologists who have contributed at least several patients each to this study: Dr J Beattie, Dr D Darnell, Dr T Diamond, Dr G Fulcher, Dr S Grant, Dr I Hales, Dr A Jameson, Dr A Joasoo, Dr F Lomas, Assoc Prof JD Wilson, Dr A McElduff, Dr J Miller, Professor S Posen, Dr M Prowse, Dr P Rohl, Dr M Rosman, Dr J Stiel, Dr R Slobodniuk, Dr C White and Dr E Wilmshurst. We also thank the many other physicians and endocrinologists who have each contributed one or two patients. References Welbourn RB. The history of endocrine surgery. New York: Praeger, 1990. Heath H. Clinical spectrum of primary hyperparathyroidism: Evolution with changes in medical practice and technology. J Bone Miner Res 1991; 6: S63-S70. Heath H, Hodgson SE, Kennedy MA. Primary hyperparathyroidism: incidence, morbidity and potential economic impact in a community. N Engl J Med 1980; 302: 189-193. Chan AK, Duh Q-Y, Katz MH, et al. Clinical manifestations of primary hyperparathyroidism before and after parathyroidectomy. Ann Surg 1995; 222: 402-414. Warner J, Clifton-Bligh P, MacElduff A, et al. Longitudinal changes in forearm bone mineral content in primary hyperparathyroidism. J Bone Miner Res 1991; 6 Suppl 2: 91-95. Christenson T, Hellstrom K, Wengle R, et al. Prevalence of hypercalcemia in a health screening in Stockholm. Acta Med Scan 1976; 200: 131-137. Boonstra CE, Jackson JE. Serum calcium survey for hyperparathyoidism: results in 5000 clinical patients. Am J Clin Pathol 1971; 55: 523-526. Consensus Development Conference Panel. Diagnosis and management of asymptomatic primary hyperparathyroidism: consensus development conference statement. Ann Int Med 1991; 114: 593-597. Deaconson TF, Wilson SD, Lemann J Jr. The effect of parathyroidectomy on the recurrence of nepherolithiasis. Surgery 1987; 102: 910-913. Posen S, Clifton-Bligh P, Reeve TS, et al. Is parathyroidectomy of benefit in primary hyperparathyroidism? QJM 1985; 54: 241-251. Turken SA, Cafferty M, Silverberg SJ, et al. Neuromuscular involvement in mild asymptomatic primary hyperparathyroidism. Am J Med 1989; 87: 553-557. Delbridge LW, Marshman D, Reeve TS. Neuromuscular symptoms in elderly patients with hyperparathyroidism: improvement with parathyroid surgery. Med J Aust 1988; 149: 74-76. Kristoffersson A, Bostrom A, Soderberg T. Muscle strength is improved after parathyroidectomy in patients with hyperparathyroidism. Br J Surg 1992; 79: 165-168. Joborn C, Hetta J, Palmer M, et al. Psychiatric symptomatology in patients with primary hyperparathyroidism. Ups J Med Sci 1986; 91: 77-87. Joborn C, Hetta J, Lind L, et al. Self rated psychiatric symptoms in patients operated on because of primary hyperparathyroidism and in patients with longstanding mild hypercalcemia. Surgery 1989; 105: 72-78. Burney R, Jones K, Coon J, et al. Assessment of patient outcomes after operation for primary hyperparathyroidism. Surgery 1996; 120: 1013-1019. Kaplan EL, Yashiro T, Salti G. Primary hyperparathyroidism in the 90s. Ann Surg 1991; 215: 300-317. Ljunghall S, Hellman P, Rasted J, Akersorm G. Primary hyperparathyroidism: epidemiology, diagnosis, and clinical picture. World J Surg 1991; 15: 681-687. Van Heerden JA, Grant CS. Surgical treatment of primary hyperparathyroidism: an institutional perspective. World J Surg 1991; 15: 688-692. Harrison BJ, Wheeler MH. Asymptomatic primary hyperparathyroidism. World J Surg 1991; 15: 724-729. Palmer M, Adami H-O, Bergstrom R, et al. Mortality after operation for primary hyperparathyroidism. A follow-up of 441 patients operated on during 1956-1979. Surgery 1987; 102: 1-7. Hedback G, Oden A, Tisell L. The influence of surgery on the risk of death in patients with primary hyperparathyroidism. World J Surg 1991; 15: 399-407. Miller DC. Preoperative localisation and interventional treatment of parathyroid tumours: when and how. World J Surg 1992; 15: 706-715. Serpell JW, Cambell PR, Young AE. Pre-operative localisation of parathyroid tumours does not reduce operating time. Br J Surg 1991; 78: 589-590. Malmaaeus J, Granberg PO, Halvorsen J, et al. Parathyroid surgery in Scandinavia. Acta Chir Scand 1988; 154: 409-413. (Received 1 Jul, accepted 26 Nov, 1997) Authors' details Department of Surgery, University of Sydney, and Royal North Shore Hospital, Sydney, NSW. Leigh W Delbridge, MD, FRACS, Professor of Surgery; Nidal A Younes, MD, Fellow in Endocrine Surgery; currently, Surgeon, University of Jordan Hospital, Amman, Jordan; Ana I Guinea, BSc(Psych)(Hons), Psychologist; Thomas S Reeve, MD, FRACS, Emeritus Professor. Department of Endocrinology, University of Sydney, and Royal North Shore Hospital, Sydney, NSW. Phillip Clifton-Bligh, FRACP, Clinical Associate Professor in Medicine; Bruce G Robinson, MD, FRACP, Professor of Medicine (Endocrinology), University of Sydney, and Kolling Institute of Medical Research, Sydney, NSW. Reprints will not be available from the authors. Correspondence: Professor L W Delbridge, Department of Surgery, Royal North Shore Hospital, St Leonards, NSW 2065. E-mail: leighd AT med.su.oz.au - Readers may print a single copy for personal use. No further reproduction or distribution of the articles should proceed without the permission of the publisher. For permission, contact the Australasian Medical Publishing Company Journalists are welcome to write news stories based on what they read here, but should acknowledge their source as "an article published on the Internet by The Medical Journal of Australia <http://www.mja.com.au>". <URL: http://www.mja.com.au/>

Leigh W Delbridge · Nidal A Younes · Ana I Guinea · Thomas S Reeve · Phillip Clifton-Bligh · Bruce G Robinson

Overnight hospital stay for carotid endarterectomy Bernard M Bourke and Denis C Crimmins MJA 1998; 168: 157-160 For editorial comment see Lord Abstract - Introduction - Methods - Results - Discussion - References - Authors' details - - ©MJA1998 Abstract Objective: To determine if overnight hospital stay after carotid endarterectomy (CEA) is feasible and safe in the Australian setting. Design: Case series with follow-up of 4-11 months (mean, 7 months). Patients and setting: All patients undergoing primary CEA performed by a vascular surgeon (B M B) between 30 May and 11 November 1996. Surgery was performed in one of four hospitals (a district general public hospital with about 400 beds and three private hospitals) in the Gosford area of New South Wales. Interventions: CEA using regional anaesthesia and sedation, after diagnosis by duplex ultrasound scan, avoiding cerebral angiography and intensive care; planned discharge after overnight hospital stay; review at one month and duplex ultrasound scan at four months. Outcome measures: Length of hospital stay and complications. Results: 65 patients were admitted for CEA during the study period and 59 were scheduled for overnight stay (one had "re-do" surgery, two remained longer for reasons unrelated to carotid artery disease, and three had been scheduled before the change to overnight stay). 54 (92%) were discharged on the first postoperative day, and only three required readmission within 30 days (for urinary retention, angina and reperfusion syndrome). There were no deaths, no myocardial infarctions and no recognised instances of cerebral ischaemia during follow-up. Conclusion: CEA can be performed safely without cerebral angiography or intensive care, with over 90% expectation of a single night's stay in hospital. Introduction Carotid endarterectomy, once controversial, has now been established by major prospective trials as highly efficacious in preventing cerebral ischaemic events in patients with carotid artery disease.1-4 Reflecting this evidence, the annual number of carotid endarterectomies performed in Australia increased from 3384 in the 1991-92 financial year to 5427 in 1994-95.5 Nevertheless, use of carotid endarterectomy in asymptomatic patients is still questioned, because of its potential for serious complications6 and claims that it is not cost effective.7 In addition, the operation is now facing challenges from new procedures -- carotid angioplasty and stenting -- which are claimed to be effective, with shorter hospital stays.5 However, studies in the United States have shown that the traditional four- to six-day hospital stay after carotid endarterectomy can be reduced and postoperative intensive care avoided without compromising patient safety.8-10 Further, recent major advances in non-invasive methods of diagnosing extra cranial carotid disease (eg, duplex ultrasound)11,12 have raised questions about the need for cerebral angiography (itself carrying about 1% risk of stroke13) before surgery. In addition, although general anaesthesia is used for carotid endarterectomy at most Australian centres (with notable exceptions14), many major overseas centres favour regional cervical or local anaesthesia.15,16 These have the advantage of allowing the procedure to be performed in patients who are unfit for general anaesthesia. We tested the hypothesis that carotid endarterectomy can be performed in the Australian setting with reduced resources (avoiding cerebral angiography and intensive care) while maintaining an acceptable standard of care. We report the outcomes for the first 59 patients scheduled for carotid endarterectomy with overnight hospital stay in the practice of the surgical author (B M B). Methods Subjects and setting Subjects were all patients who had primary carotid endarterectomy performed by B M B between 30 May and 11 November 1996. All were scheduled for overnight postoperative hospital stay, unless longer stay was indicated for management of conditions unrelated to carotid artery disease. Surgery was performed in one of three private hospitals or the major district general public hospital in the Gosford area of New South Wales. Patients had either been referred by general practitioners or other specialists with symptoms of internal carotid artery disease, or signs such as audible cervical bruit, or had been undergoing regular ultrasound monitoring of the internal carotid artery (eg, patients with coronary artery disease or previously treated contralateral coronary disease). Carotid endarterectomy was offered to: Patients with typical symptoms of internal carotid artery disease (retinal ischaemia, cerebral hemispheric transient ischaemic attacks or completed stroke) and 60% or greater stenosis at the origin of the appropriate internal carotid artery; Patients with typical symptoms but less than 60% stenosis, if duplex ultrasound examination showed carotid plaque to be the likely cause of symptoms; Asymptomatic patients with 80% or greater stenosis; and Asymptomatic patients with 60%-79% stenosis, if the stenosis had progressed from less than 60% within six months or they specifically requested surgery. No patients who fulfilled these criteria were considered "medically unfit" for the procedure. All agreed to surgery. Duplex ultrasound Stenosis of the internal carotid artery was assessed by duplex ultrasound examination (combination of Doppler and B-mode ultrasound) performed according to internationally recognised standards17 either by B M B or by one of two fully accredited vascular technologists. Stenosis was graded as none to moderate (< 60%), severe (60%-79%) or critical (80%-99%), according to the haemodynamic parameters of Zwiebel18 (Box 2, below). As degree of stenosis determined by duplex ultrasound examination may differ from that determined by cerebral angiography, we also applied the more stringent haemodynamic criteria of Carpenter et al19 to ultrasound results. The decision to use duplex ultrasound examination routinely instead of cerebral angiography was based on comparison of the results of the two tests and the atheromatous plaque removed at carotid endarterectomy (the "ultimate" gold standard) in about 400 of B M B's previous patients (unpublished data). Since then, duplex ultrasound had been used routinely instead of cerebral angiography for a further 400 patients before the present study. Surgery At the preoperative consultation, B M B explained that the patient would be admitted on the day of surgery and discharged on the first postoperative day. The availability of a relative or friend competent to care for the patient was also assessed. Preadmission assessment (full blood count, coagulation screen, estimation of blood urea, creatinine and electrolytes, electrocardiography and chest x-ray) were performed in the week before surgery. All procedures were performed in conscious patients with regional cervical block and sedation given by the method of Davies et al.14 After surgery, patients were nursed in the recovery room for four to six hours and then either sent back to a general surgical ward (in the public hospital), or assigned a special nurse in a general or high dependency ward (in the private hospitals). All patients were reviewed by medical staff twice on the first postoperative day and discharged in the care of a relative or friend that afternoon with instructions to contact the surgeon about any concerns, unless complications requiring further hospitalisation were apparent. The first 12 patients in the series were telephoned by B M B on the second postoperative day, but this practice was discontinued as it was considered unnecessary and alarming for the patient. Follow-up All patients were followed up with a consultation with B M B a month after surgery and a duplex ultrasound scan four months after surgery, to assess symptom recurrence and development of disabling stroke or significant surgical or medical complications. Patients continue to be followed up at 6- to 12-month intervals. An independent clinician (D C C) retrospectively reviewed all patients' hospital records to verify major morbidity (stroke or myocardial infarction), mortality and consecutiveness of the series, usually within a month of patient discharge. Results Subjects Of the 65 patients who had carotid endarterectomy between 30 May and 11 November 1996, 59 were scheduled for overnight postoperative stay. The other six were not scheduled for overnight stay as they were undergoing "re-do" surgery (one patient), had been scheduled before the change to overnight stay and therefore had not been counselled about a short stay (three patients), or needed longer hospital stay for reasons unrelated to carotid artery disease (two patients). One of these asked to remain in hospital for cataract surgery, and the other was taking warfarin and was admitted under the care of a cardiologist four days before surgery, and remained four days after, for stabilisation of this drug. Independent assessment of these patients' records by D C C to verify the reason for exclusion showed that none experienced complications which would have prolonged their stay more than a night had they been entered into the study. The 59 patients scheduled for overnight stay comprised 38 men and 21 women. Their characteristics are shown in Box 2, and the indications for carotid endarterectomy in Box 3. Forty of the 59 patients had symptoms of carotid artery disease (either typical, such as carotid transient ischaemic attacks, or possible, such as non-hemispheric ischaemia) plus 60% or greater stenosis of the internal carotid artery, according to the criteria of Zwiebel.18 All but three of these also met the criteria of Carpenter et al19 for 60% or greater stenosis. Of the five patients with typical symptoms but less than 60% stenosis, duplex scan showed the carotid plaque to be hypoechoic and, in B M B's opinion, the likely cause of the symptoms. At operation in all five, the plaque was found to be soft, friable and ulcerated, supporting this assessment (Figure 1). All but two of the asymptomatic patients had either a critical (80%-99%) stenosis or a severe (60%-80%) and progressive stenosis (Figure 2). The two exceptions had severe but non-progressive stenosis and requested surgery after the risks and benefits and results of recent trials had been explained to them . Cerebral angiography was used to confirm duplex ultrasound results in one of the 65 patients, as heavy calcification made imaging less than optimal. Of the 54 patients with 60% or greater stenosis by the criteria of Zwiebel,18 all but three also met the criteria of Carpenter et al19 for this degree of stenosis. Therefore, we were confident that almost all would have fitted the criterion of at least 60% stenosis by angiography as applied in the Asymptomatic Carotid Atherosclerosis4 and North American Symptomatic Carotid Endarterectomy1 trials. Hospitalisation and surgery Thirty-six of the operations were performed in a public hospital and 23 in private hospitals. Fifty-three of the 59 patients were admitted on the day of surgery. Another two were already in hospital for investigation of cerebral symptoms under the direction of a neurologist, and four were admitted the previous day (two because of transport difficulties that prevented them reaching hospital early enough on the morning of surgery and two because of administrative errors). In five operations, the arteriotomy was closed primarily, while in 53 operations (90%) a vein patch was inserted; no synthetic patches were used. The remaining operation was aborted after the skin incision, as the patient had an extreme panic attack. Nine patients (15%) required cerebral protection with a shunt after evidence of intraoperative cerebral ischaemia. Average operation times were: without patch, 77 minutes (range, 65-105 minutes), and with patch, 98 minutes (range, 70-145 minutes). Two patients with angina were sent to the intensive care unit for the first post- operative night. Outcome measures Hospital discharge: 54 of the 59 patients were discharged on the first postoperative day (Day 1), and four on Day 2 (two were kept in hospital because of angina and one because of nausea, and one refused to go home on the first day, despite agreeing preoperatively). The remaining patient was not discharged until Day 3 because of prolonged headache. Complications: Complications are shown in Box 4. There were no deaths or cases of cerebral ischaemia or myocardial infarction. All complications, except the reperfusion syndrome, became apparent within one day of surgery. The patient with reperfusion syndrome was readmitted with a generalised seizure on Day 5 and required ventilatory support for 13 hours, but made a complete recovery after 24 hours. Cerebral computed tomography showed frontal oedema associated with a small area of possible cerebral haemorrhage, but no evidence of cerebral ischaemia. Clinically, there were no neurological deficits. Two other patients were readmitted within 30 days, one on Day 3 for urinary retention, which had not been present at discharge, and one on Day 23 for unstable angina. The latter had known inoperable coronary artery disease and had been admitted several times before carotid endarterectomy for angina. Patient acceptance of overnight stay: Discharge on Day 1 was very well accepted by all but one patient, who had agreed to it preoperatively, but in the event refused to go home until Day 2. Most patients were relieved in that discharge the day after surgery seemed to "defuse" the magnitude of the procedure for them. Follow-up: All patients were followed up, for an average of 7 months (range, 4 to 11 months). At one-month follow-up, all previously symptomatic patients reported relief of symptoms, including eight who had had non-hemispheric ischaemia. None reported new neurological symptoms, and there were no significant medical or surgical complications (ie, requiring hospitalisation or outpatient treatment). Four-month duplex scanning showed that three patients had evidence of intimal hyperplasia (peak systolic velocity in the internal carotid artery greater than 130 cm/s), and one patient had asymptomatic occlusion of the internal carotid artery. The remaining endarterectomised vessels were widely patent without abnormality. Discussion The results of this case series show that carotid endarterectomy can be performed safely with basic resources, avoiding both carotid angiography and intensive care, and with reduced postoperative hospital stay. Complications in this series compared favourably with those found in previous, major surveys (0-7.5% major complication rate,1,3,21 depending on the type of patient). No deaths or strokes occurred in our series. The only major complication was one case of reperfusion syndrome. This is a rare event after carotid endarterectomy (incidence, 0.4%), and is thought to be caused by revascularisation of a chronically ischaemic cerebrovascular bed. It may occur up to seven days after operation and may progress to seizures, cerebral haemorrhage and death.22 It is usually preceded by a headache, and, although minor headache is common after carotid endarterectomy, patients with severe headaches should not be discharged. Importantly, all complications except the reperfusion syndrome became apparent within one day of surgery, supporting the proposal that longer monitoring in hospital is not needed for patients who have shown no signs of complications within this time. Avoiding cerebral angiography and intensive care and shortening postoperative hospital stay reduces the cost of carotid endarterectomy. In the United States, Ascer et al showed that averting standard angiography and limiting hospital stay to one night saves US$6900 per patient.23 Avoiding cerebral angiography also reduces costs indirectly; the investigation itself can cause stroke,11 which must be included in the overall cost analysis. According to an NHMRC cost analysis, a stroke costs the community $40 243.5 Reducing the cost of carotid endarterectomy could make the procedure more cost effective in asymptomatic patients. In symptomatic patients with high grade stenosis, it is highly cost effective because of its great efficacy in reducing stroke (17% absolute risk reduction).1 In contrast, in asymptomatic patients, it is calculated that 19 carotid endarterectomies are needed to prevent one stroke in five years,4 leading commentators to question its cost effectiveness in these patients.7 However, the dilemma is that most patients experience no warning symptoms of stroke, and if preventive measures are to have an impact they need to be directed to the asymptomatic population as well as the symptomatic population.24 As our study involved only 59 patients, it can be regarded as only a pilot study. However, it confirms the conclusions of overseas studies that carotid endarterectomy can be performed safely with use of only basic resources.8-10,12,13 Since this study, a further 108 consecutive patients have undergone carotid endarterectomy performed by B M B with overnight stay. We have had no reason to alter the overnight policy. Proponents of alternative treatments for carotid bifurcation disease, such as carotid angioplasty and stenting, will not only have to prove the efficacy of these procedures, but will also need to justify the costs of using cerebral angiography (often more than once), disposables (sheaths, wires, angiography catheters, angioplasty balloons, contrast agents) and stents, together with the costs of any short or long term complications. References North American Symptomatic Carotid Endarterectomy Trial Collaborators: Beneficial effect of carotid endarterectomy in symptomatic patients with high-grade carotid stenosis. N Engl J Med 1991; 325: 445-453. North American Symptomatic Carotid Endarterectomy Trial (NAS-CET) Steering Committee: North American Symptomatic Carotid Endarterectomy Trial: Methods, patient characteristics, and progress. Stroke 1991; 22: 711-720. European Carotid Surgery Trialists' Collaboratory Group: MRC European Carotid Surgery Trial: Interim results for symptomatic patients with severe (70-99%) or with mild (0-29%) carotid stenosis. Lancet 1991; 337: 1235-1243. Asymptomatic carotid atherosclerosis study group. Endarterectomy for asymptomatic carotid artery stenosis. JAMA 1995; 273: 1421-1428. National Health and Medical Research Council. Clinical practice guidelines: prevention of stroke -- the role of anti-coagulants, anti-platelets and carotid endarterectomy. Canberra: NHMRC, 1996. Easton JD, Serman DG. Stroke and mortality rate in carotid endarterectomy: 228 consecutive operations. Stroke 1977; 8: 565-568. Hankey GJ. Asymptomatic carotid stenosis: how should it be managed? Med J Aust 1995; 163: 197-200. Hirko MK, Morasch MD, Burke K, et al. The changing face of carotid endarterectomy. J Vasc Surg 1996; 23: 622-627. Collier PE. Are one-day admissions for carotid endarterectomy feasible? Am J Surg 1995; 170: 140-143. Calligaro KD, Dougherty MJ, Raviola CA, et al. Impact of clinical pathways on hospital costs and early outcome after major vascular surgery. J Vasc Surg 1995; 22: 649-660. Goodson SF, Flanigan P, Bishara RA, et al. Can carotid duplex scanning supplant arteriography in patients with focal carotid territory symptoms? J Vasc Surg 1987; 5: 551-557. Kuntz KM, Skillman JJ, Whittemore AD, Kent KC. Carotid endarterectomy in asymptomatic patients -- is contrast angiography necessary? A morbidity analysis. J Vasc Surg 1995; 22: 706-716. Hankey GJ, Warlow CP, Sellar RJ. Cerebral angiographic risk in mild cerebrovascular disease. Stroke 1990; 21: 209-222. Davies MJ, Mooney PH, Scott DA, et al. Neurologic changes during carotid endarterectomy under cervical block predict a high risk of post-operative stroke. Anesthesiology 1993; 78: 829-833. Imparato AM, Ramirez A, Riles T, Minzer R. Cerebral protection in carotid surgery. Arch Surg 1982; 117: 1073-1078. Connolly JE. Carotid endarterectomy in the awake patient. Am J Surg 1985; 150: 159-165. Thiele BL, Jones AM, Hobson RW, et al. Standards in non-invasive cerebrovascular testing: report from the Committee on Standards for Non-invasive Vascular Testing of the Joint Council of the Society for Vascular Surgery and the North American Chapter of the International Society for Cardiovascular Surgery. J Vasc Surg 1992; 15: 495-503. Zwiebel WJ. Introduction to vascular ultrasonography. 3rd ed. Philadelphia: WB Saunders, Harcourt Brace Jovanovich, 1992: 123-132. Carpenter JP, Lexa FJ, Davis JT. Determination of sixty percent or greater carotid artery stenosis by duplex Doppler ultrasonography. J Vasc Surg 1995; 22: 697-705. Rosenberg N. CRC handbook of carotid artery surgery: facts and figures. 1st ed. Boca Raton, Fla: CRC Press, 1989. Riles TS, Fisher FS, Lamparello PJ, et al. Immediate and long term results of carotid endarterectomy for asymptomatic high grade stenosis. Ann Vasc Surg 1994; 8: 144-149. Reigel MM, Hollier LH, Sundt TM, et al. Cerebral hyperperfusion syndrome: a cause of neurologic dysfunction after carotid endarterectomy. J Vasc Surg 1987; 5: 628-634. Ascer E, Pollina RM, Lorensen E, et al. Carotid endarterectomy for asymptomatic stenosis. A safe simplified cost effective approach [abstract]. Cardiovasc Surg 1995; 1 : 46. 3 Suppl. Bock RW, Gray-Weale AC, Mock PA, et al. The natural history of asymptomatic carotid artery disease. J Vasc Surg 1993; 17: 160-171. (Received 20 Feb, accepted 26 Sep, 1997) Authors' details Gosford Hospital, Holden Street, Gosford, NSW. Bernard M Bourke, FRACS, DDU, Vascular Surgeon; Denis C Crimmins, FRACP, Neurologist. Reprints: Dr B M Bourke, 213 Albany Street North, Gosford, NSW 2250. Readers may print a single copy for personal use. No further reproduction or distribution of the articles should proceed without the permission of the publisher. For permission, contact the Australasian Medical Publishing Company Journalists are welcome to write news stories based on what they read here, but should acknowledge their source as "an article published on the Internet by The Medical Journal of Australia <http://www.mja.com.au>". <URL: http://www.mja.com.au/>

Bernard M Bourke · Denis C Crimmins

Health Care Establishing a collaborative service model for primary mental health care A collaborative project between general practitioners and mental health services, which links a consultation-liaison model with shared care, was piloted with success. This article provides a broad overview of the service model and the stages in its development. Graham N Meadows MJA 1998; 168: 162-165 Introduction - History of the CLIPP service - Activity of the service - Benefits and costs - Summary and prospects - Acknowledgements - References - Authors' details - - More articles on Psychiatry Introduction Improving collaboration between mental health services and general practitioners in caring for people with serious mental illness is an aim of Commonwealth Government policy.1,2 Recent documents examining the psychiatry workforce have also recommended stronger links between specialist and generalist services in this area.3-5 Mental health care needs may often be more appropriately met by general practitioners than by long term specialist care. This will be true for many patients with anxiety disorders and depression, but also for selected patients with psychotic disorders. General practitioner involvement with people with continuing mental illness may also provide an opportunity to address unmet physical health needs,6 and may ultimately have an impact on the high rates of physical morbidity and mortality associated with major mental disorder.7Various models of consultation-liaison links between psychiatric services and GPs have been described in reports from the United Kingdom.8-11 Although this area of activity in Britain was described as "the silent growth of a new service" in 1984,12 a more recent review noted that many such schemes had not proceeded beyond pilot phase. This review stressed the need for further evaluations, including cost-benefit evaluation, in response to this situation.13 In Australia, a pilot scheme in Newcastle, New South Wales, providing consultation-liaison attachments to GPs was initially reported positively,14 but a later viewpoint paper alluded to less encouraging aspects, and the project did not move beyond pilot phase.15 A recent survey of psychiatrists in South Australia suggests considerable enthusiasm for collaboration in consultation-liaison models,16 but revealed little actual activity in this area. The Consultation Liaison in Primary Care Psychiatry (CLIPP) service model developed in the Northwest Melbourne Area Mental Health Service promotes collaboration between GPs and public mental health services in managing psychiatric problems. CLIPP is now established, with recurrent funding from State public mental health services, and is being extended into another area mental health service. This article describes the CLIPP model and the activity involved in ensuring its continuation beyond the pilot phase. History of the CLIPP service In 1993, Health and Community Services Victoria received Federal Government National Mental Health Initiative funding expressly for promoting shared care initiatives in mental health. Early in 1994, staff of the Northwest Melbourne Area Mental Health Service and local GPs (represented by the Division of General Practice) proposed a pilot project, for which they were granted $97 000 over two years. These funds supported a half-time psychiatric nurse case manager for 18 months and most of the cost of a half-time psychologist project officer for two years. The area mental health service contributed about four half-day sessions per week of psychiatrist time. Consultation-liaison attachments, although they are well liked and help to improve GP confidence, have been criticised as doing little to enhance GPs' involvement with the care of the seriously mentally ill.15 Shared care arrangements for specific patients with serious mental disorder may result in GPs feeling that public mental health services are not helping them with the types of problems they see most frequently. We aimed to counter these problems by combining the two approaches. Consultation-liaison attachments were set up first. General practitioners were recruited by mail through the Division. Interested GPs were followed up with personal visits by project staff, then with fortnightly visits by a psychiatrist to each practice (similar to the British "liaison-attachment" model9). Details of the consultation-liaison attachment system are shown in Box 1. Three months after setting up these attachments, shared care was initiated by asking participating GPs to accept patients referred from the area mental health service. At this point, the number of psychiatrist consultation appointments for patients referred by GPs was generally reduced to two each session to allow time for discussion of the shared care patients referred from the area health service. Operation of the shared care system is described in Box 2. During 1995, consultation-liaison attachments were set up with seven group practices of between two and 12 GPs. By late 1995, all of these practices were accepting patients transferred from the area mental heath service. The CLIPP service was recognised by a National Mental Health Achievement Award in 1996, in the category of prevention and health promotion. The project was reported to Health and Community Services Victoria, with an account of the development, and a cost-benefit analysis supported by work carried out in the area mental health service.17 Activity of the service During its first two years, CLIPP provided care to over 220 patients through the clinical consultation-liaison service, patients having been referred by 31 of the 40 GPs from the seven participating group practices. It has facilitated the transfer of over 90 clients from the area mental health service into shared care with 28 GPs, including GPs from each participating practice. Box 3 lists the clinical diagnoses of the patients in these two groups. The most common single impediment to the transfer of care to GPs -- affecting about 15 patients -- is drug costs. Some regimens are free to patients under area mental health service care, but prohibitively expensive (under the Pharmaceutical Benefits Scheme) for others. A change to a rebated alternative drug may sometimes remove this impediment, but is not always clinically appropriate. One partial solution would be for a GP to see patients every two to four weeks for clinical monitoring, while the psychiatrist sees them around six-monthly, prescribing through the area mental health service pharmacy. Among patients transferred to GPs, telephone follow-up by area mental health service staff has found that 90% report being satisfied with their management. One year after transfer to GP care, 60% felt their physical health care had improved with the increased GP input. In some 20% of cases, review of GP case notes showed that newly identified physical health problems had been treated. Two patients whose care was transferred to GPs died of natural causes. No other cases have so far been lost to follow-up. An unexpected referral route developed during the pilot phase of the service, with public community mental health services making one or two referrals a month to GPs working with CLIPP. This is appropriate for patients who present directly to these specialist services, but whose needs could be as well, or better, met in this augmented primary care model. Benefits and costs The pilot project was reported to Human Services Victoria in June 1996. While the clinical service had been running for little over a year, and was hardly ready for summative evaluation, the following benefits could be claimed on the basis of a combination of qualitative and quantitative data. The model: provides a large number of courses of GP care, with (through consultation-liaison attachments) specialist assessment and supervision; provides a valued educational opportunity for interested GPs; complements general practice care with systematic monitoring and community outreach (provided by the area mental health service) when necessary. This augments the capacity of GPs to provide care to individuals with continuing mental disorder; allows area mental health care to be provided locally and with more flexibility; shows high levels of consumer acceptability; and promotes the physical health of clients transferred to GPs. A detailed cost-effectiveness report of the project is in press.18 Costing analyses included projecting estimates of the activity of the service forward up to two years, and examining the projected cost effectiveness that could be reasonably expected from the service over that time. A simplified version of this analysis can be rendered as follows. The total cost of the CLIPP service was compared with the cost of providing care through area mental health services for the 110 patients in CLIPP who would otherwise have been cared for in the area mental health service. This group comprised 90 patients transferred from the area mental health service to GPs, 10 patients seen in the consultation-liaison attachments who would otherwise have had their care transferred to the area mental health service, and 10 patients diverted from triage at the area mental health service to GPs. Two patterns of area mental health service care that would otherwise have been required for the patients transferred into shared care through CLIPP were identified. These were 1-25 community service contacts per year, and 25-50 such contacts per year. The median cost per case for area mental health service care was estimated to be $623 and $2261 per annum, respectively.17 The 110 patients transferred to the CLIPP service were estimated to have originated from these two groups in a ratio of 4:1 (88 patients at $623 and 22 patients at $2261 per annum). From these estimates, the annual costs of mental health service care for the 110 patients transferred to GPs within CLIPP is $104 566. By comparison, the total cost of the CLIPP program (including the cost of staff initally funded through the Commonwealth Government grant, and psychiatrists whose time was committed from area mental health service budgets) was estimated at within $1000 of this sum. Hence, the model can be argued to be cost neutral for the area mental health service, but with the advantages to patients described earlier. The evaluation report was positively received by Human Services Victoria. In late 1996, commitment was made to continue funding for the project through the Western Region of Human Services Victoria, and extended to developing another project along similar lines in a nearby area of metropolitan Melbourne. Further development of the service is now an active process of participation between Western Region as purchasers and the Western Health Care Network as providers, with the support of academic staff from the University of Melbourne. Summary and prospects It has been previously shown that GP consultation-liaison services can be implemented in Australia.14 In the CLIPP model, the strengths of the relationships established through consultation-liaison links have been harnessed in support of effective shared care. Combining these two activities means that a cost-effectiveness case can be presented which is more convincing than that for a consultation-liaison service alone. Experience of this development suggests that, if such schemes are to continue, they need to meet the needs and expectations of all stakeholders with purchaser and provider roles -- GPs, patients, case managers, psychiatrists, and mental health service managers. Current plans for further development of the CLIPP model include use of computer-based reminder systems to support GPs in managing transferred patients, and providing periodic group education sessions for participating GPs. Over the next three years, CLIPP will provide the setting for a Commonwealth Department of Health and Family Services examination of process and outcome in shared care (General Practice Evaluation Program Grant 518). The new study uses a quasi-experimental design to compare processes and outcomes of care in the shared care setting with those in a community mental health service. Further systematic analysis of the consultation-liaison service is under way. This will include description of GP referral patterns, management suggestions from psychiatrists, determinants of outcomes, and a further cost-benefit analysis. I believe CLIPP to be a very useful model for improving collaboration between GPs and psychiatric services. It has allowed a diverse group of practitioners to work together in ways that transcend funding and organisational barriers in the interests of sensible arrangements for the delivery of health care. Acknowledgements Human Services Victoria for funding through Western Metropolitan Region budgets, particularly Mr John Hedditch for support in expansion of the service. The Commonwealth Government for funding through Mental Health Initiative funding and General Practice Divisional resources; also, Dr Philip Hegerty of the Northwest Division, Dr Bob Long, and the many other GPs involved. The project team from the Northwest Area mental health services: Dr Lynette Joubert, Mr Guy Dobson, Dr Carol Harvey, Dr Rajeev Kumar, Dr Philip Price, and Dr Michael Wong. Western Health Care Network management staff, particularly Mr George Shaw, for support. Mr Paul Mcrone, health economist at the Institute of Psychiatry, London, for assistance with cost-benefit analyses. References Australian Health Ministers' Advisory Council. National mental health plan. Canberra: AGPS, April 1992. Commonwealth Department of Human Services and Health. Better health outcomes for Australians: national goals, targets and strategies for better health outcomes into the next century. Canberra: AGPS, 1994. Solomon S and Associates, Buckingham B and Associates, Epstein M. Report of consultancy for the mental health workforce committee on medical workforce financing arrangements. Melbourne: The Associates, 1993. McKay B and Associates. Proposals for change final report: optimum supply and effective use of psychiatrists. Canberra: Bernie McKay and Associates, 1996. McKay B and Associates. Issues and options supplementary paper: optimum supply and effective use of psychiatrists: Canberra: Bernie McKay and Associates, 1996. Brugha TS, Wing JK, Smith BL. Physical health of the long term mentally ill in the community. Is there unmet need? Br J Psychiatry 1988; 155: 777-781. Allebeck P. Schizophrenia: a life shortening disease. Schizophrenia Bull 1989; 15: 81-89. Strathdee G, King M. The interface between primary and secondary psychiatric care. In: Williams P, Wilkinson G, Rawmsley K, editors. The scope of epidemiological psychiatry: Essays in honour of Michael Shepherd. London: Routledge, 1989: 420-433. Creed F, Marks B. Liaison psychiatry in general practice: a comparison of the liaison-attachment scheme and shifted outpatient models. J R Coll Gen Pract 1989; 39: 514-517. Strathdee G, McDonald E. Innovations: establishing psychiatric attachments to general practice: a six stage plan. Psychiatr Bull 1992; 154: 72-76. Strathdee G. Psychiatrists in primary care: the general practitioner viewpoint. Fam Pract 1988; 5: 111-115. Strathdee G, Williams P. A survey of psychiatrists in primary care: the silent growth of a new service. J R Coll Gen Pract 1984; 34: 615-618. Gask L, Sibbald B, Creed F. Evaluating models of working at the interface between mental health services and primary care. Br J Psychiatry 1997; 170: 6-11. Carr VJ, Donovan P. Psychiatry in general practice: a pilot scheme using the liaison-attachment model. Med J Aust 1992; 156: 379-382. Carr VJ, Reid ALA. Seeking solutions for mental health problems in general practice. Med J Aust 1996; 165: 435-436. Barber R, Williams AS. Psychiatrists working in primary care: a survey of general practitioners' attitude. Aust N Z J Psychiatry 1996; 30: 278-286. Meadows G, Gielewski H, Falconer B, et al. The pattern of care model: a tool for planning community mental health services. Psychiatr Serv 1997; 48: 218-223. Meadows G, Joubert L, Mcrone P, Dobson G. Consultation, collaboration and cost effectiveness: reflections on four years of shared care in Melbourne. In: Ellis P, editor. Community care -- working together. Proceedings of the Geigy Psychiatric Symposium; 1997 Dec 3-5; Wellington, New Zealand. Sydney: Novartis. In press. Received 1 Sep, accepted 22 Dec, 1997 Authors' details Department of Psychiatry, University of Melbourne, Royal Park Hospital, Melbourne, VIC. Graham N Meadows, MRCP(UK), FRANZCP, Senior Lecturer. Reprints: Dr G N Meadows, Department of Psychiatry, University of Melbourne, Royal Park Hospital, Private Bag 3, PO Parkville, VIC 3052. E-mail: g.meadowsATmedicine.unimelb.edu.au 1: Format for consultation-liaison attachments in the CLIPP project Psychiatrists provide consultation services for any patient referred by GPs. This service is provided at the general practice clinic. For group practices, visits are usually fortnightly, and 2-3 patients are seen per consultation Specific forms, which include a global impression rating by the GPs, are used to document the consultancy request from the GPs and responses by psychiatrists; follow-up forms are completed by GPs after three months, and include a repeat of the previous global impression rating and a change score. These forms are complemented by face-to-face discussion between GPs and psychiatrists during the fortnightly consultation at the GP's clinic, during which any patient can be discussed, including those not seen personally by the psychiatrist. Psychiatrist consultations are generally specifically intended to leave continuing care of each patient with the GP. General practitioners have been remunerated at the hourly rate for "Divisional activities by GPs" through a Divisional seeding grant for time spent in discussion with psychiatrists. The Royal Australian College of General Practitioners recognises this activity as continuing medical education, and awards two CME points per hour, or one point per patient referred. Back to text 2: Format for shared care in the CLIPP project Case managers within the area mental health service identify candidate patients -- typically clinically stable, without recent relapse, with fair to good insight, and with some social support. Patients are referred to the CLIPP nurse, who prepares the transfer. A concise summary of diagnosis, history, and treatment adherence is prepared from the case notes. Impediments to transfer are identified and acted upon where possible; the outcome of this action is recorded. The CLIPP nurse drafts a management plan and arranges a first CLIPP appointment, at which the GP, psychiatrist and patient discuss the draft and establish the plan for continuing management. The GP takes over the primary responsibility for the care of the patient. A patient registration and tracking system maintained by area mental health service staff supports the GP in maintaining continuity of care and provides information about satisfaction and other quality assurance. As part of this tracking system, an administrator maintains an electronic diary of due dates for review of each patient. Clinical staff then review patients three-monthly by telephone contact with the patient and by checking the GP's case notes for continued contact. Management plans usually also recommend that psychiatrists review patients every 6-12 months. Back to text 3: Diagnoses of CLIPP service patients, by origin of referralBroad diagnostic category*Consultation- liaison referralsReferrals from mental health service to GPsDepression and dysthymia105 12Adjustment disorder40--Anxiety disorders281Problems related to substance abuse11--Schizophrenia856No diagnosis8Bipolar disorder711Eating disorder4--Pain disorder3 --Axis ii (personality disorder) diagnosis only2--Delusional disorder12Somatoform disorder1--Dementia of Alzheimer type1--Dissociative fugue1--Medication-induced movement disorder1--Schizoaffective disorder--10Brief psychosis--1Totals22193* From Diagnostic and statistical manual of mental disorders, fourth edition. Washington, DC: American Psychiatric Association, 1994. Back to text

Graham N Meadows

Notable Cases Echinacea-associated anaphylaxis Raymond J Mullins A woman with atopy experienced anaphylaxis after taking, among other dietary supplements, a commercial extract of echinacea. Hypersensitivity was confirmed by skinprick and RAST testing. Regular ingestion of echinacea by up to 5% of surveyed patients with atopy, combined with detection of echinacea-binding IgE in atopic subjects (19% by skin testing; 20% with moderate to strong reactivity by RAST testing), raises the possibility of severe allergic reactions, even with first-time use, due to cross-reactivity with other structurally similar allergens. Patients with atopy should be cautioned about the risk of developing life-threatening reactions to complementary medicines, including echinacea. MJA 1998; 168: 170-171 For the full text of this article, see the pdf version

Raymond J Mullins

Improving the mental and physical health of unemployed people: why and how? Strategies that reduce the negative effects of joblessness are likely to benefit us all MJA 1998; 168: 177-178 Unemployment has been a recurring social problem throughout this century, and a permanent feature of economic life in Australia and other industrialised countries since the early to mid 1970s. Our current unemployment rate hovers between 8% and 9%,1 although the Australian Council of Social Services estimates that there could be just as many "hidden unemployed", who do not feature in official statistics.2 The "hidden unemployed" comprise two main groups: those who do not register for work because of illness or for personal reasons or who have given up job-seeking (discouraged workers), and those who hold part-time and casual jobs but would prefer full-time work (the underemployed).3 The official unemployment rate equates to some 800,000 people out of work, with about a third of these being long-term unemployed (ie, out of work for 12 months or more).1 It is now well documented that for many the experience of unemployment brings with it physical and mental health problems. Furthermore, longitudinal studies have shown that the negative effects of unemployment have largely resulted from people moving from being employed to being unemployed, and are not associated with workers with few skills or inadequate personal resources "drifting" into joblessness.4 Not all groups in our community are equally affected by unemployment. Australian Aboriginals, people from non-English-speaking backgrounds, especially recent migrants, and people with disabilities are especially vulnerable. Young people are another seriously disadvantaged group. Three articles in consecutive issues of the Journal will highlight the health problems faced by unemployed people. The first will review the evidence for the detrimental effects of unemployment on health (see Mathers and Schofield in this issue of the Journal);5 the second will address the particular problems of young unemployed people (Morrell et al, MJA 1998; 2 March);6 and the third will look at how the health system can respond to the health problems of unemployed people (Harris et al, MJA 1998; 16 March).7 Satisfactory employment has many benefits that unemployed people are denied. These benefits are firstly financial, but equally important are the assignment of identity and status, the increased social contact, being part of a collective purpose and joint effort, and being able to engage in regular activity.8 The substantial cuts to income that most unemployed people face are associated with real and relative deprivation that, in itself, can be psychologically destructive. Poverty clearly affects physical and psychological well-being. It also reduces confidence and restricts personal agency and empowerment.9 Loss of income and resulting poverty can be especially psychologically destructive for adults, as they are likely to have financial and family commitments. For young people, failure to find satisfactory employment may adversely affect their psychological development and have negative long term consequences. The lowered self-confidence associated with unemployment10 can reduce the number and types of jobs applied for, restrict the uptake of training, and inhibit engagement in self-employment or cottage/craft industries. Furthermore, lack of confidence also means that low levels of commitment, motivation and effort will be brought to bear, perseverance will be low, and, in particular, the capacity to persist with an activity in the face of setbacks or adversity will be greatly reduced. Unemployed people with poor self-confidence will timidly pursue occupational possibilities, and are likely to desist altogether in the face of repeated failures. This pattern will repeat itself in other areas of these people's lives, impinging on their ability to cope with their financial commitments and their social and family life. Not only does unemployment reach beyond those who are jobless, and put at risk the well-being of their partners and children,11,12 but there is also growing evidence that high levels of unemployment have an adverse effect on those in the workforce, with job insecurity being associated with elevated stress levels.13 The picture is further complicated by increasing numbers of people who, on the one hand, are underemployed, and those who, on the other hand, are in full-time employment but are required to work ever-longer hours to maintain their jobs. Little is known about the health effects on these two groups. Despite the evidence of the detrimental effects of unemployment on health, there is little debate in the community about these issues. The assumption remains that it is a temporary problem and that the emphasis should be on encouraging people to enter training or to find work. This is despite the fact that unemployment and underemployment are now long-standing and near-universal problems. This assumption has resulted in too few resources being expended on the development and evaluation of interventions to reduce the adverse effects of unemployment. Harris et al, in the final article in this series, document the few interventions that have been tried, and outline possible strategies to address this problem.7 It is important to reduce the negative effects of unemployment to minimise individual misery of unemployed people, as well as to benefit their families and the commun ity in general. While this task does include the development and implementation of individual health and well-being programs, the solution also lies in our responses to the changing nature of work and how we will structure our major institutions in the next century. We need to develop policies and strategies to reduce the stigma of joblessness. The right of all to be able to engage in meaningful and community-sanctioned activities that bring with them opportunities for financial security is central to reducing the debilitating effects of unemployment. Unemployment is a long-standing problem. It is not likely to disappear in the short to medium term. Income support from government sources will inevitably continue, and could do so without the stigma with which it is currently associated and at levels that ensure that unemployed people do not live in poverty. This, together with an expansion of reciprocal relationships between the community and unemployed people (as is currently being tested under the "work-for-the-dole scheme" which commenced in December 1997), offer some scope for setting a new agenda in this area. Peter A Creed Lecturer, School of Applied Psychology Griffith University, Gold Coast, QLD Australian Bureau of Statistics. 1997 Year Book Australia. No 97. Canberra: AGPS; 1997 (Catalogue No. 1301.0.). Spiers R. Growing problem of long term unemployed. Financial Review (Sydney) 1991; 11 Mar: 6. Canadian Public Health Association. 1996 Discussion paper on the health impact of unemployment. Winefield AH, Tiggemann M, Winefield HR. Growing up with unemployment: longitudinal study of its psychological impact. London: Routledge, 1993. Mathers CD, Schofield DJ. Health consequences of unemployment: the evidence. Med J Aust 1998; 168: 178-182. Morrell S, Taylor R, Kerr C. Unemployment and young people's health. Med J Aust 1998; 168. In press. Harris E, Webster I, Harris M, Lee P. Unemployment and health -- the healthcare system's role. Med J Aust 1998; 168. In press. Jahoda M. Work, employment and unemployment: values theories and approaches in social research. Am Psychol 1981; 36: 184-191. Fryer D. Benefit agency? Labour market disadvantage, deprivation and mental health. Psychologist 1995; 8: 265-272. Bandura A. Self efficacy: the exercise of control. New York: Freeman, 1997. McLoyd VC. Socialization and development in a changing economy: the effects of paternal job loss on children. Am Psychol 1989; 44: 293-302. McKee L, Bell C. His unemployment, her problem: the domestic and marital consequences of male unemployment. In: Allen S, Watson S, Purcell K, Wood S, editors. The experience of unemployment. Basingstoke: Macmillan 1986: 134-149. Winefield AH. Unemployment, occupational stress and psychological distress. In: Hicks R, Creed P, Patton W, Tomlinson J, editors. Unemployment: developments and transitions. Brisbane: Australian Academic Press, 1995: 77-88. Readers may print a single copy for personal use. No further reproduction or distribution of the articles should proceed without the permission of the publisher. For permission, contact the Australasian Medical Publishing Company Journalists are welcome to write news stories based on what they read here, but should acknowledge their source as "an article published on the Internet by The Medical Journal of Australia <http://www.mja.com.au>". <URL: http://www.mja.com.au/>

Peter A Creed

The health consequences of unemployment: the evidence Colin D Mathers and Deborah J Schofield For editorial introduction see Creed Mathers and Schofield, from the Australian Institute of Health and Welfare, review recent studies, including Australian research, on the health effects of unemployment and the mechanisms by which unemployment causes adverse health outcomes. The relationship is complex: ill-health also causes unemployment, and confounding factors include socioeconomic status and lifestyle. However, longitudinal studies with a range of designs provide reasonably good evidence that unemployment itself is detrimental to health and has an impact on health outcomes -- increasing mortality rates, causing physical and mental ill-health and greater use of health services. (MJA 1998; 168: 178-182) Introduction - Health outcomes and determinants - Conclusions - Acknowledgements - References - Authors' details - - ©MJA1998 Introduction The first convincing evidence of a causal relationship between unemployment and ill-health came from a British longitudinal study in the mid 1980s.1,2 At the same time an influential series of reviews in the British Medical Journal (1985; 291), and a related book,3 drew widespread attention to the effects of unemployment on health. Australian studies during the 1980s and early 1990s demonstrated adverse effects of unemployment on the mental health of young people4,5 (see Morrell et al in the next issue of the Journal [2 March 1998] for a review of the health consequences of youth unemployment6), and in the past few years the National Health Strategy and reports from the Australian Institute of Health and Welfare have documented worse health among unemployed Australians using a wide range of health indicators.7-9 There has been subsequent vigorous debate about the direction of causality: Does unemployment cause a deterioration in health? Are the sick more likely to become unemployed (health selection effects)? Or are both unemployment and poor health associated with another, underlying, causal factor such as socioeconomic disadvantage? Here, we review the Australian and international evidence for an association between unemployment and adverse health outcomes and the potential causal mechanisms for this association. We searched the literature for the past decade using MEDLINE and chose key studies evaluating current knowledge about the relationship between unemployment and ill-health for a range of health outcomes and determinants: mortality rates, mental health, lifestyle factors, and health service use. We have included some pivotal studies drawn from a longer time span, and refer to existing recent relevant reviews. We placed particular emphasis on recent Australian studies. In assessing the evidence, it is important to keep in mind that unemployment is a complex and diverse experience rather than an easily categorised exposure variable like tobacco smoking, and that its effects will be mediated by a large number of social and individual factors. Health outcomes and determinants Mortality rates Analyses of aggregated population data from the 1930s onwards have demonstrated correlations between unemployment levels and mortality rates, such as maternal mortality, infant mortality and deaths from rheumatic heart disease.3 In the 1970s, Brenner found correlations for several countries at the population level between annual unemployment levels and mortality rates over periods of up to 40 years.10-12 However, these studies have been seriously criticised and cannot be used to infer causation.3,13 Other studies looked at correlations between variations in unemployment levels and death rates for geographical regions and obtained generally consistent findings.14,15 Again, such studies cannot be used to infer causation, as unemployment may be correlated at the population level with other factors causing increased mortality. Much more convincing evidence for causality was obtained from longitudinal studies (not specifically set up to examine unemployment and health) in several countries in the 1980s. A 1% sample of census records was used to analyse mortality in unemployed men aged 15 to 64 in England and Wales in 1971 and 1981.1,2 For both samples, employment meant lower mortality rates than the average (the "healthy worker" effect). Those unemployed who had a pre-existing illness or disability had mortality rates over three times higher than the average. Those who were unemployed but not ill at census time showed a 37% excess mortality over the following 10 years (95% confidence interval [CI], 22%-52%). In all social classes, the mortality rate of unemployed people was higher than that of the employed, particularly for deaths from cardiovascular disease, lung cancer, accidents and suicide. If health selection were occurring among the "not-ill" unemployed, despite a strong incentive to declare illness to obtain additional benefits, then there would have been higher mortality rates at the beginning of the follow-up period that would have fallen with time. This pattern occurred among the group chronically ill at the beginning of follow-up, but the excess mortality for those "not-ill" and unemployed rose slightly over the 10-year follow-up. These findings were confirmed and extended by other large longitudinal studies in Europe.16-18 A census-linked study in Denmark found a 40%-50% excess death rate among the unemployed after adjustment for occupation, housing category, geographical region and marital status,16 with suicides and accidents being prominent causes of excess mortality. Excess mortality was also found among unemployed women, although the relative mortality was somewhat higher for unemployed men. There was also an inverse association between relative mortality and the level of local unemployment. A Finnish longitudinal study of linked census data for people aged 25-59 years found a higher mortality rate in unemployed than employed people, after controlling for age, education, type of occupation and marital status.18 Mortality ratios for men and women unemployed for the first time in 1990, at a time of low national unemployment, were 2.11 (95% CI, 1.76-2.53) and 1.61 (95% CI, 1.09-2.36), respectively. The comparable ratios for those unemployed for the first time in 1992, when the national employment rate was very high, were much lower: men, 1.35 (95% CI, 1.16-1.56); women, 1.30 (95% CI, 0.97-1.75). A recent prospective cohort study of over 6000 British men, aged 40-59 years, and continuously employed for the five years before initial screening, found that men who experienced some unemployment or retired during the five years after screening were twice as likely to die in the following 5.5 years as those who remained continuously employed.19 After excluding men who became unemployed or retired because of ill-health, and adjusting for the effects of socioeconomic status, smoking, alcohol consumption, body weight and health indicators, the mortality ratio was 1.47 (95% CI, 1.10-1.96) for the unemployed group and 1.86 (95% CI, 1.34-2.59) for the retired group. In Australia, the serious limitations of the information recorded on death certificates have prevented analysis of mortality rates for unemployed people.8 However, an early Australian study20 found a correlation between aggregate unemployment trends and death from ischaemic heart disease (see also Morrell et al6 for suicide rate and unemployment rate correlations in Australia). Mental health Cross-sectional and longitudinal studies3,13 (including longitudinal studies of young Australians4,5 -- see Morrell et al6 ) have consistently found poorer psychological health in unemployed compared with employed people. A prospective US study clearly showed that men aged 35-60 years who became unemployed had higher levels of depression and anxiety than those who remained employed.21 A study of unemployed German men over the age of 45 found higher levels of psychological distress and that these regressed with re-employment or retirement.22 As with mortality, it is likely that the impact of unemployment on mental health is dependent on general social conditions. An earlier British study found lower levels of psychological distress among men from areas of chronically high unemployment than among men living in areas of low unemployment23 -- perhaps reflecting better adaptation through networks, community solidarity and lower costs of living in areas with higher unemployment. In Australia, several longitudinal studies have shown poorer psychological health in unemployed compared with employed young people and that these differences first emerge after entry into the labour market. Furthermore, when unemployed young people find jobs their mental health improves.4,5,24 Disease and disability Cross-sectional population studies have documented more illness and poorer self-reported health in unemployed people after adjusting for the effects of social status and other variables.8,25-27 An analysis of population survey data for Britain in 1991-92 found that, after controlling for education level and type of occupation, unemployed men and women had over twice the odds of having a limiting chronic illness compared with employed men and women, and a 60%-80% higher odds of reporting poor health.27 Factory-closure studies, which minimise the effects of health selection, have found increased levels of medically diagnosed health problems, particularly cardiovascular disease and its risk factors, including high serum cholesterol levels and high blood pressure.28-30 Despite occasional studies finding no association between unemployment and ill-health,31 the balance of evidence suggests that unemployment, at least among adult men, has an association with physical health, and in particular with cardiovascular disease. In Australia, unemployed men and women aged 25-64 years were found to be about twice as likely to report being in poor or fair health (as opposed to good or excellent health); they also reported 30%-40% more serious chronic illnesses and 20%-30% more recent health problems than their employed counterparts. Differences in levels of smoking, risk drinking, physical inactivity and overweight did not account for these health differences (Figure).8 Lifestyle risk factors Several studies have found higher rates of smoking and alcohol use and poorer diet among unemployed people,32-35 although a causal link has not been confirmed.36,37 A prospective study of British men aged 40-59 years found no evidence that they increased their smoking or drinking on becoming unemployed, but they were more likely to gain weight.36 The men who became unemployed had higher levels of smoking and alcohol consumption at the initial screen, emphasising the importance of controlling for lifestyle factors (and socioeconomic status). In Australia, the 1989-90 National Health Survey found that unemployed Australians were about 40%-50% more likely to be smokers, but were less inactive than the employed;8,38 unemployed men were 57% more likely to have had measured hypertension than employed men (95% CI, 13%-100%).8 Health service use Cross-sectional studies and factory-closure studies have documented higher levels of hospital admissions, doctor visits and outpatient visits among the unemployed.28,39 These are usually interpreted as an indicator of poorer health. There has been little attempt to determine whether the higher level of health service use by the unemployed is commensurate with increased need. In Australia, the 1989-90 National Health Survey found that unemployed men visited the doctor significantly more often, unemployed women reported significantly more hospital outpatient visits, and unemployed people used more pharmaceutical agents.8,40 A multivariate analysis suggested that reported health status largely accounted for reported differentials in health service use.8 Differences between demographic groups Unemployment falls disproportionately on younger and older workers and on already disadvantaged groups such as low income earners, recent migrants, indigenous people and workers with few skills.26,27,41,42 In one study, the difference in levels of ill-health between unemployed and employed men was found to be greater for those in lower socio economic groups (as defined by education level and last occupation).27 This may be a result of lower re-employment prospects among the unskilled or their fewer financial resources to cushion the effects of unemployment, although health selection may also play a greater role in lower socio economic groups. Excess mortality caused by unemployment is highest for middle-aged men, and there is also some evidence that unemployment affects mental health more for this group than others. Health status reported by unemployed women tends not to be as low as for unemployed men, and similarly unemployed women report fewer health risk factors.8,27,38 All these studies emphasise that the health consequences of unemployment are not the same for all groups in the population. This point is also underlined by the few studies that have found groups of employed people whose health is worse than that of unemployed people.5 Interpersonal effects There have been surprisingly few studies of the effects of unemployment on the health of other family members. The British Office of Population Censuses and Surveys longitudinal study found a 20% excess mortality (95% CI, 4%-41%) among wives of unemployed men.2 Other adverse effects of unemployment on family life include higher risk of separation and divorce, domestic violence, unwanted pregnancy, increased perinatal and infant mortality, poorer infant growth and increased health service use.3,13,37,43 In Australia, children whose parents are unemployed, compared with those with one or more of their parents employed, were reported to have around 26% more serious chronic illnesses (95% CI, 3%-55%), 20%-30% more visits to the doctor, and around twice as many outpatient visits.44 Aetiology Few studies of unemployment and health have advanced beyond questions of causality and the magnitude of health effects to investigate aetiological issues. At the individual level, poverty, psychological impacts and health-related behaviours and lifestyle changes have been suggested (Box 1). Conclusions Although the relationship between unemployment and health is complex and varies for different population groups, there is consistent evidence from different types of studies that unemployment is associated with adverse health outcomes. Health selection effects do occur, but longitudinal studies provide reasonably convincing evidence that unemployment has a direct effect on health over and above the effects of socioeconomic status, poverty, risk factors, or prior ill-health. Our review highlights several priorities for future research (Box 2). Acknowledgements The authors thank Sarojini Martin for assistance in literature searches. References Moser KA, Goldblatt PO, Fox AJ, Jones DR. Unemployment and mortality: comparison of the 1971 and 1981 longitudinal study census samples. BMJ 1987; 1: 86-90. Moser K, Goldblatt P, Fox J, Jones D. Unemployment and mortality. In: Goldblatt P, editor. Longitudinal study: mortality and social organisation. London: OPCS, 1990. 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Canberra: Australian Institute of Health and Welfare, 1995. (Health Monitoring Series No. 3.) Marmot MG, Bosma H, Hemingway H, et al. Contribution of job control and other risk factors to social variations in coronary heart disease incidence. Lancet 1997; 350: 235-239. Harris E, Webster I, Harris M, Lee P. Unemployment and health: the healthcare system's role. Med J Aust 1998; 168. In press. Saunders P. Employment growth and poverty: an analysis of Australian experience 1983-1990. Sydney: University of New South Wales, Social Policy Research Centre, 1990. (Discussion Paper No. 25.) Authors' details Australian Institute of Health and Welfare, Canberra, ACT. Colin D Mathers, BSc(Hons), PhD, Principal Research Fellow, Health Division; Deborah J Schofield, BSpThy, GradDipCompSc, Project Manager, National Public Health Indicators. Reprints will not be available from the authors. Correspondence: Dr C D Mathers, Principal Research Fellow, Australian Institute of Health and Welfare, GPO Box 570, Canberra, ACT 2601. E-mail: colin.mathers AT aihw.gov.au Readers may print a single copy for personal use. No further reproduction or distribution of the articles should proceed without the permission of the publisher. For permission, contact the Australasian Medical Publishing Company Journalists are welcome to write news stories based on what they read here, but should acknowledge their source as "an article published on the Internet by The Medical Journal of Australia <http://www.mja.com.au>". <URL: http://www.mja.com.au/>

Colin D Mathers · Deborah J Schofield