Objectives: To analyse rates of avoidable hospitalisations in Aboriginal and non-Aboriginal residents of the Northern Territory, 1998–99 to 2005–06, and to consider the implications for primary care interventions.Design and setting: Retrospective descriptive analysis of inpatient discharge data from NT public hospitals.Main outcome measures: Avoidable hospitalisations by age, sex, Aboriginality and condition, with annual time trends.Results: Between 1998–99 and 2005–06, Aboriginal people in the NT had an avoidable hospitalisation rate of 11 090 per 100 000 population, nearly four times higher than the Australian rate of 2848 per 100 000. The rate for non-Aboriginal NT residents was 2779 per 100 000. During this period, the average annual increase in avoidable hospitalisations was 11.6% (95% CI, 11.0%–12.1%) in the NT Aboriginal population and 3.9% (95% CI, 3.3%–4.5%) in the non-Aboriginal population. The greatest increase occurred in those aged ≥ 45 years, and was primarily attributable to diabetes complications.Conclusions: The significantly higher rates of avoidable hospitalisations in NT Aboriginal people reflect the emerging epidemic of chronic disease in this population, highlight barriers to Aboriginal people accessing effective primary care, and emphasise the extent of potential health gains with appropriate interventions.

Shu Q Li MPH, MB, BNursing · Natalie J Gray MIPH(Hons), MB BS(Hons), BSc/LLB(Hons) · Steve L Guthridge MB BS, MPH, FAFPHM · Sabine L M Pircher MPH, BNutrDiet

Objective: To evaluate the role of the adult health check for Aboriginal and Torres Strait Islander people aged 15–54 years, in an urban Indigenous primary health care setting.Design, setting and participants: Cross-sectional study of Indigenous patients recruited opportunistically from the Inala Indigenous Health Service between 1 June 2007 and 31 July 2008.Main outcome measures: Newly identified cardiovascular risk factors, investigations ordered and performed, interventions and new diagnoses made.Results: 413 patients out of a possible 509 consented to participate (93% were Aboriginal). High prevalences of cardiovascular risk factors such as smoking (67%), being overweight and obese (61%), harmful levels of alcohol consumption (36%), and depression (23%) were found. The adult health checks resulted in new investigations (in 82% of participants), lifestyle advice (67%), vaccinations (42%), referrals (62%) and new medications (49%). New diagnoses resulting from the health checks included depression (6%), a harmful level of alcohol consumption (4%), chlamydia infection (4%), hypertension (3%) and diabetes (3%). Pap smears were performed in 47% of women as a result of the health check.Conclusions: The adult health check for Aboriginal and Torres Strait Islanders aged 15–54 years is a viable vehicle for evaluating health status, identifying chronic disease risk factors and for implementing preventive health care.

Geoffrey K P Spurling MB BS, FRACGP · Noel E Hayman MB BS, MPH, FAFPHM · Anna L Cooney RN

In 2006, with outstanding cooperation from Department of Corrective Services staff at Cessnock Correctional Centre, two Justice Health staff made a huge step in walking together in the constant fight for Aboriginal health. In a mere six and a half hours, 88 Aboriginal offenders — 100% of the Aboriginal population in that centre — were screened for markers of kidney disease. We had been fighting for years to get renal screening into the jails. Finally it happened! A special renal screening research project funded by the Hunter New England Area Health Service was to be carried out in three facilities in the Hunter Valley and northern New South Wales: Cessnock, St Heliers (Muswellbrook) and Tamworth. We were offered five days to do three jails. If anyone could pull it off, I reckoned I could. I’ve been an Aboriginal Health Worker in the system since 1985, longer than most of the “lifers” — but they let me out from time to time, I like to remind everyone. I did some serious thinking and strategic planning on just how to pull this off at the Cessnock site. I had 66 Aboriginal patients spread over five wings and various other locations, and no nurse or place to do the screening. A well-meaning officer jokingly said to me on hearing about it, “How many you wanting to do?” “Sixty-six, officer — the lot”, I answered. He laughed and retorted, “Impossible, you’ll never do it . . . I’d say 30, tops . . . and three days. It’s a bet”. They were fighting words. “You’re on.” That was how this story started. What I first needed was a nurse and a place to do it. I fronted the clinic and did some passionate Aboriginal-kidney-health-at-an-all-time-low talking to the Justice Health Nursing Unit Manager. She was already four nurses down that day, but after some drastic roster raping and creative roster placing, I got my Aboriginal male nurse for the project. We needed a toilet for collection of specimens. Urine testing is not the easiest thing to do in a hurry. Next we needed to give the patients-to-be an incentive. I headed into the prison-yards — “Calling all Kooris!” I’d kick that Koori grapevine into gear fast to get the word out. The bait was a Koori-coloured red, yellow and black water bottle. One each. It wasn’t much, but then most of these guys have almost nothing. To make sure everyone knew what was happening and how important it was to get 66 permission forms signed beforehand, we arranged afternoon tea for the next day. Hot buttered damper with syrup and billy tea were promised. That hit the spot. Full turn-up next day and 66 names and forms were signed and collected, with spares kept at the ready for any new arrivals. The officer’s challenge was taken by all offenders with wry grins and much laughing as hot buttered damper with syrup was consumed with lots of lip-smacking and licking of fingers and enthusiastic agreement as we planned D-Day down to the minute. The jobs of rounding everyone up and getting them from point A to point B were allocated. Twelve patients at a time was agreed — ready to roll out, bladders brimming, as others returned. They were ready — all they needed was complete cooperation from all officers concerned on the day. D-Day arrived. By 7.30 am I was already in the yards as the wings were emptying for breakfast. We rallied the Kooris to win the bet as soon as methadone parade was over. We had 66 for sure, and others signing on, as the transports arrived with more offenders. It was shaping up well. By mid morning, the Aboriginal Delegate (the community leader of all Aboriginal offenders of the centre) had 22 more signed permissions: 100% of the Aboriginal population in the Cessnock facility, now 88 in total. All in. “Bring it on Aunt, we’re ready for them!” The war cry went up. Something was about to break the boredom that day. Everybody knew it and was ready to play a part — not just the Kooris. The operation was fully planned for speed. As each patient arrived in the allotted clinic area, I would give him a specimen cup to write his name and ID number on; record his height and weight; then send him on to the nurse to have his specimen tested and blood pressure taken. Each patient was warned — any abnormality and he would be listed to see the doctor. After receiving their water bottles, each group returned to the yards to spread the word of encouragement and help rally the rest. When the queue got down to five, the Aboriginal Delegate and I would take off down the “avenue” to gather the next 12. This is where the story gets humorous. Some of the old laggers who were taking it easy, sitting in the sun on the walls along the avenue and generally bored silly with the monotonous routine of their surroundings, started to take a keen interest in the comings and goings and the unusual enthusiasm of the Koori lads that morning. At this point they decided to get in on the act too. As they spied them striding fast (you don’t run inside jails) towards the avenue gates, the laggers would call out, “Come on you Koori lads, Aunt is coming for you, boots and all”. Fact is, Kooris never hurry for anyone or anything, it’s kind of a principle — but when they heard that call, “there was movement in the yards, for the word had passed around, that Aunt was coming fast and the boots were gaining ground”, they were gathering and forming up already in lines. The old laggers sitting on the walls were well into the game by now and sent out a new call to the avenue rover: “Hey chief, they’re on their way back now . . . big bunch of ’em coming up fast”. This alerted the rover to open up each of the three security gates promptly for us to pass through. On the third trip down, the old laggers called out in jovial fashion, “Go Aunt, go! We’re taking book on this, you know”. That called for some laughter and cheering as the patients passed each time. The applause and calls of encouragement from the crowd, which had now swelled considerably, added a definite flavour to the day. Our project had become a talking point. Some officers remarked later that the Aboriginal health exercise lifted morale that week for the whole jail. It had been all good. By lunchtime, we were out of resources. Hunter Area Health had only sent 50 packs. We’d ordered more, but were still waiting for them. I phoned again — they were on their way. We still had two wings and the work crews to get through. Cuppa was in order, but then word came — “The parcels are here and on their way down!” Yes! The officers were met halfway. They had two big bags of water bottles and the testing gear. Cheers rang out from the avenue throng and the officers were heroes for a minute or so. Because of the tight security in the next areas (Maximum), it took a little longer, but we finished by 2.30 pm, still with time to catch the Aboriginal lads returning from work in their assigned prison duties for the day. Because of prison staff shortages, early lockdown in Maximum meant they had to be escorted individually down two flights of stairs to take part. With great officer cooperation, it happened. We needed to complete the project before total jail lockdown at 4.00 pm, and we did. Hoping we’d managed to test everyone, the pair of us wearily trudged back through the long jail yards past all five wings to the clinic. Our step lightened as we heard the inmates calling to us, “Good on you fellas, did you get them all? . . . Deadly job you two, a great day!” Everyone wanted to know if they had reached the goal, headed by the officer who’d bet we couldn’t do it. With a grin on his face he asked if we’d done all 66 prisoners, looking very confident we hadn’t. I was happy to bring him up to date. Count done: 100% of current Aboriginal offenders had participated and all had been tested. By the clock, we had done 88 patients in six and a half hours! The officer was astounded: “That was some feat you two pulled off . . . I can’t believe it . . . glad I didn’t put money on it!” The serious side of the screening research project showed itself in the results. Of the 88 Aboriginal offenders, 14 screened positive for microalbuminuria and many more were positive for other high-risk chronic illnesses such as hypertension and diabetes. The next two jails visited were St Heliers and Tamworth. At St Heliers, all 37 Aboriginal offenders were screened. Of these, 13 tested positive, and again many were referred for other high-risk illnesses. At Tamworth, 42 Aboriginal people were screened (one refusing), with 14 being positive and one dangerously positive. In all, over the three sites, 167 renal screenings were carried out, resulting in 42 abnormal kidney readings. As a result of this successful renal screening project, one new Aboriginal position has been created for the area: the Coordinator Aboriginal Renal/Health Promotion will be working with the Aboriginal Health team for two years within the existing 16 Aboriginal Chronic Care Program sites. The Program gives us vital information on the cardiovascular health of Aboriginal offenders well in advance of onset of cardiovascular disease. The renal health component is a nice addition to the Program. Aboriginal people normally don’t access the mainstream Justice Health centres in the jails because Aboriginal staff from many external Aboriginal Medical Services can’t regularly visit the centres any more due to a lack of staff and funding. This is why we need Aboriginal Health Workers in every jail, especially in those with a high percentage of identified Aboriginal offenders. Change — stalled a decade ago — is slowly starting to happen again. Twenty per cent of the male client base and 31% of the female client base in NSW prisons are Aboriginal people, with levels as high as 50% in younger offenders. Despite the Royal Commission into Aboriginal Deaths in Custody1 20 years ago, which recommended that culturally appropriate medical care be provided to offenders, with access to Aboriginal Health Workers wherever possible, and despite what you read in annual reports since then, Justice Health 10 years ago adopted an unofficial policy of mainstreamed take-it-or-leave-it medical service to Aboriginal offenders. It is now slowly moving away from this stance by employing its own Aboriginal Health Workers as part of the health centre staffing profile, beginning with one of the newer facilities at Wellington in midwestern NSW. Visiting Aboriginal Medical Services staff should be welcome to work with members of their community who are in jail, but clearly, Aboriginal Health Workers are needed within the system itself, trained to go into the yards with the Aboriginal Delegates to encourage the brothers to access and be tested at the Health Centre. The hardest part of the process is moving the prisoners within the jail. Locked gates, classification, segregation, non-association, constant lockdowns, inter-jail transfers without notice, request forms denied or simply lost — all add to the burden of self-destructive thinking that offenders bring into jail with them. Even knowing of a serious medical problem, they will often give up and cease to care. Aboriginal people in general, and prisoners in particular, are also dealing (or not dealing, as the case may be) with the blight of long-term systemic racism. A popular notion (unfortunately given scientific credibility by Charles Darwin) is that they are the lowest form of human life — one step above the apes: [H]ow little can the hard-worked wife of a degraded Australian savage, who uses hardly any abstract words and cannot count above four, exert her self-consciousness, or reflect on the nature of her own existence? [quoting Büchner] . . . At some future period . . . the civilised races of man will almost certainly exterminate and replace throughout the world the savage races.2 I commend you instead to the words of Kevin Gilbert — a self-educated Wiradjuri man and former offender — writing 100 years later, after doing 15 years for murder: As Aborigines began to sicken physically and psychologically, they were hit by the full blight of an alien way of thinking. They were hit by the intolerance and uncomprehending barbarism of a people intent only on progress in material terms, a people who never comprehended there could be cathedrals of the spirit as well as of stone. Their view of Aborigines as the most miserable people on earth was seared into Aboriginal thinking because they now controlled the provisions that allowed blacks to continue to exist at all. Independence from them was not possible. White people’s devaluation of Aboriginal life, religion, culture, and personality caused the thinking about self and race that I believe is the key to modern Aboriginal thinking. As Robert Kantilla said, “Suffering is that the white people class them as the lowest person on earth”. My thesis is that Aboriginal Australia underwent a rape of the soul so profound that the blight continues in the minds of most blacks today. This psychological blight, more than anything else, causes the conditions we see in reserves and missions today and is repeated down the generations . . . [T]hey have been patterned into that stereotype, and they do live it.3 No more is needed to explain the present and ongoing over-representation of Aboriginal people in the prison population, or their generally poor health. And the solution? Kevin Gilbert goes on to say that it starts with your education, and I agree. But it’s a special education. It’s a pity I don’t have room to quote him more, because he just blows Charles Darwin away. And healthwise, whether you’ve been injured by a truck or by generations of white racism, it’s the same solution, believe it or not — education. Kooris, Gooris, Murris and all Aboriginal people, your health education can start right here, with you learning these principles: Recovery and ongoing maintenance of your good health starts, first and foremost, with a free decision by you to take primary personal responsibility for it. Yes, you can do it, and yes, you are worth it. You need education — information, strategies, and especially role models. Find them, and stick with the strength, or else . . . For the many Aboriginal people locked in prison — especially those also locked in their self-destructive rituals of negativity, resentment and blame — experience shows that the process of health education in prison is only likely to start when they are targeted, brought together and encouraged into the caring hands of Justice Health’s wonderful Health Centres, with their specially trained and enthusiastic Aboriginal Health Workers.

Beverley F Spiers BEd(Aboriginal Adult Ed), GradDipAdultEd

Objective: Design, setting and participants: A population-based study of 789 240 term singleton births in public and private hospitals in 2001–2004, using data from the National Perinatal Data Collection.Main outcome measures: Third- and fourth-degree perineal injury, requirement for high level of neonatal resuscitation, Apgar score < 7 at 5 minutes, admission to neonatal intensive care unit or special care nursery, and perinatal death.Results: 31.4% of the term singleton births occurred in private hospitals. After adjusting for maternal age, Indigenous status, parity, smoking status, diabetes, hypertension, remoteness of usual residence, and method of birth, the rates of all adverse outcomes studied were higher for public hospital births. For women, the adjusted odds ratio (AOR) for third- or fourth-degree perineal injury was 2.28 (95% CI, 2.16–2.40). For babies, the odds of a high level of resuscitation (AOR, 2.37; 95% CI, 2.17–2.59), low Apgar score (AOR, 1.75; 95% CI, 1.65–1.84), intensive care requirement (AOR, 1.48; 95% CI, 1.45–1.51) and perinatal death (AOR, 2.02; 95% CI, 1.78–2.29) were all higher in public hospitals.Conclusion: For women delivering a single baby at term in Australia, the prevalence of adverse perinatal outcomes is higher in public hospitals than in private hospitals.

Stephen J Robson MPH, MD, FRANZCOG · Paula Laws BAppPsych(Hons) · Elizabeth A Sullivan MB BS, MPH, MMed(Sexual Health)

The aim of the National Health Priority Area (NHPA) initiative is to promote cooperation between government and non-government organisations to monitor, report on and develop strategies to improve health outcomes for Australians. The seven existing NHPAs (cancer control, injury prevention and control, cardiovascular health, mental health, diabetes mellitus, asthma and musculoskeletal conditions) were selected on the basis of their profound burden on the health of Australians. Up to eighty per cent of Australians will experience back pain at some point in their lives and 10% will experience significant disability as a result. Back pain disrupts individuals’ quality of life and accounts for an enormous cost to the community. Integrating back pain into the NHPA framework has many potential benefits, including more systematic development and implementation of programs aimed at minimising back pain-related disability by providing a focus for policy, legislation and public awareness; and promotion of best-practice management of the condition. A disadvantage of making back pain an NHPA is the risk that back pain management could become further medicalised and ineffective interventions could become more accepted. Coordinated action on back pain is needed, and integrating back pain into the NHPA framework is one solution. Informed decision making through consultation with key stakeholders is a necessary first step towards ensuring that favourable outcomes are achieved.

Andrew M Briggs BSc(PT)Hons, PhD · Rachelle Buchbinder MB BS(Hons), PhD, FRACP

Clinical record A 68-year-old man presented to our general district hospital in December 2006 with the chief complaint of sore throat, which had started abruptly 2 hours earlier. The pain was described as intense with a stabbing character. He reported minimal improvement after being given 10 mg of morphine subcutaneously. The patient did not report experiencing any cardiac or pulmonary discomfort, and he had no pertinent past medical history. His family history included one sister who had died of a ruptured aortic aneurysm. The patient was a non-smoker and denied any recent medication use. Physical examination showed that the patient’s vital signs were stable, with a normal level of consciousness, a regular pulse of 61 beats/min, and a blood pressure equal at both arms of around 115/70 mmHg. He was slightly tachypnoeic and diaphoretic. An ear, nose and throat examination did not provide any diagnostic clues as to the cause of the pharyngeal pain. Findings of a cardiovascular examination were normal apart from an audible right carotid artery bruit. No other physical abnormalities were detected. Results of laboratory tests were unremarkable, except for a markedly elevated d-dimer level (8.41 mg/L; upper limit of normal, 0.50 mg/L). Routine chest radiography was suggestive of mediastinal widening (Figure A). On the basis of these findings, a thoracic computed tomography scan was performed, which showed a 5.4 cm dissecting ascending aortic aneurysm (Figure B). The dissection involved the aortic root, ascending part of the aorta and aortic arch, and propagated into the right brachiocephalic trunk and left common carotid artery (Figure C). Transthoracic echocardiography additionally showed the presence of a bicuspid aortic valve with moderate grade 2/4 aortic insufficiency. Thoracic aortic dissection was diagnosed, classified as a Stanford type A dissection, given the involvement of the ascending aorta. A congenital bicuspid aortic valve and an ascending aortic aneurysm were predisposing factors for aortic dissection. The patient successfully underwent emergency surgery with graft replacement of the aortic valve and the dissected aortic segment. A: Chest x-ray showing mediastinal widening. The upper normal mediastinal width is defined as a mediastinum to chest-width ratio of over 0.25, measured at the level of the aortic arch (illustrated by the length of the solid line); this is noticeably exceeded in our patient (dashed line). B: Computed tomography scan showing an aneurysmatic dilatation of the ascending aorta with a classical dissection flap (black arrowhead) separating a true and false lumen. C: Propagation of the dissection process into the supra-aortic vessels (white arrows). The clinical presentation in our case was rather trivial, but the combined results from two basic investigations — an elevated d-dimer level and an abnormal chest x-ray — heightened our clinical suspicion for aortic dissection and led us to perform aortic imaging. Thoracic aortic dissection generally results from a laceration of the intimal lining of the aorta. This allows blood leakage into the aortic wall resulting in a propagating separation of the aortic media, thereby creating a false blood-filled lumen.1 Hence, the major criterion for definitive diagnosis of aortic dissection includes visualisation of a so-called intimomedial flap that divides the aorta into a true and a false lumen. Several aortic imaging techniques can be used for this purpose, of which contrast-enhanced computed tomography (CT) and transoesophageal echocardiography (TOE) are the most feasible to perform in an emergency department setting.1,2 Moreover, these investigations help to localise the dissection, thereby allowing appropriate classification. Currently, the Stanford classification of aortic dissection is the most widely adopted system.1,2 This system has the virtue of merely dividing aortic dissection into two subtypes, depending on whether the ascending aorta is involved (type A) or not (type B).1,2 While the definitive diagnosis of aortic dissection is usually straightforward, making the initial clinical diagnosis can be extremely challenging. Aortic dissection is associated with a dramatic rate of misdiagnosis and delayed recognition.3 This is no doubt partially explained by the highly variable clinical presentation of the condition. Our case is a striking illustration of why acute aortic dissection is colourfully called a “clinical chameleon”.1 Although most patients with aortic dissection present with severe chest or back pain (Box 1), the pain can be variably localised to the neck, jaw or throat.4 Throat pain occurs most often in cases of a dissection of the aortic arch, particularly when the supra-aortic vessels are involved. Our patient complained only of a sore throat, and denied having thoracic pain. Only two similar cases have been previously reported.5,6 Moreover, findings on physical examination can be very subtle.1 Classical signs consistent with the diagnosis of thoracic aortic dissection, such as an aortic insufficiency murmur or decreased femoral arterial pulsation, were not present in our patient. According to the International Registry of Acute Aortic Dissection,7 these so-called typical findings are infrequently detected during physical examination (Box 1). In our case, the only notable features of the physical examination were diaphoresis and a right carotid artery murmur. The latter was presumably the result of propagation of the dissection into the right brachiocephalic trunk. Because symptoms and signs of aortic dissection can be diverse and sometimes treacherously trivial, the initial diagnostic suspicion might rely on abnormalities observed during the basal diagnostic work-up. This routinely consists of laboratory testing with d-dimer analysis and chest radiography. d-dimer analysis has only recently come to the fore, with several studies focusing on the stringent association between the d-dimer level and aortic dissection.3,8,9 The pathophysiological mechanism for this relationship is well explained by the release of tissue factor from the dissected aortic wall. This sets off a cascade of events — activation of the extrinsic coagulation system, generation of fibrin, and secondary fibrinolysis with d-dimer formation.8 The d-dimer assay is reported to have an excellent sensitivity and negative predictive value for aortic dissection (Box 1). The quoted sensitivity is equal for both types of dissection, although absolute d-dimer values tend to be higher in type A aortic dissections as they are usually more extended.10 Given its high sensitivity and negative predictive value, d-dimer testing is an attractive tool for the diagnostic work-up of aortic dissection, particularly in the setting of a low pretest probability for aortic dissection. In such cases, a normal d-dimer result can reliably exclude the presence of aortic dissection, hence obviating the need for further investigations.9,10 Besides elevation of the d-dimer level, the clinical suspicion for aortic dissection should also be heightened if the chest radiograph is abnormal (Box 1). Mediastinal widening (relative mediastinum to chest-width ratio > 0.25;11 Figure A) is the most common radiographic finding in aortic dissection.7 Of note, absolute estimations of the mediastinal width are practically inaccurate, as these measurements are influenced by the distance between the roentgenographic source and the thorax.12 It is worth mentioning that one in three patients with aortic dissection has a normal chest x-ray.11 Thus, relying on chest radiography alone as the initial diagnostic modality is inefficient as it clearly carries a high risk of misdiagnosis. When readily available, contrast-enhanced CT and TOE are the preferred imaging modalities in an acute care setting. Both investigations have a comparable diagnostic accuracy and allow a definitive diagnosis of aortic dissection to be established.1,2 However, the diagnosis must first be suspected before it can be confirmed — this case serves as a reminder of this life-threatening condition’s wide variability in clinical presentation, and the need to maintain continuing vigilance. 1 Clinical and basic diagnostic features of thoracic aortic dissection, and percentages of patients presenting with these features who are subsequently diagnosed with Stanford type A or B aortic dissection1,2 Stanford classification Features Type A* Type B† Clinical symptoms and signs7 Presence of any pain 94% > 95% Retrosternal pain 71% 44% Interscapular pain 33% 41% Back pain 47% 64% Abdominal pain 22% 43% Blood pressure Hypotension or shock/tamponade < 25% < 5% Hypertension 35% 70% Aortic insufficiency murmur < 45% < 15% Decreased or absent peripheral pulsations < 20% < 10% Laboratory analysis8,9 d-dimer sensitivity (cutoff, 0.50 mg/L) > 95% > 95% d-dimer negative predictive value (cutoff, 0.10 mg/L) 100% Not reported Chest radiography7 Mediastinal widening 63% 56% Abnormal or blurred aortic contour 47% 53% Other radiographic features‡ < 25% < 25% * Dissection with involvement of the ascending aorta. † Dissection of the descending aorta without involvement of the ascending aorta. ‡ Such as displaced aorta, aortic calcification, tracheal displacement, pleural effusion. Lessons from practice Thoracic aortic dissection is characterised by a highly variable clinical picture, which has led to the condition being called a “clinical chameleon”. d-dimer testing can be of value in excluding aortic dissection. A normal chest x-ray does not rule out the possibility of aortic dissection. Advanced aortic imaging should be performed early in patients who have symptoms suggestive of aortic dissection in order to prevent misdiagnosis.

Sébastien Anguille MD · Aurélie M Derweduwen MD · Jeroen Lenz MD · Luc Vanuytsel MD, PhD · Frank J Cools MD

Melamine in milk The recent epidemic of urinary tract stones in young children in China has been formally linked to melamine contamination of infant formula, according to the results of a clinical study. Over 500 children aged 36 months or younger were screened in the study, which set out to determine the level of exposure to melamine, and symptoms of and predisposing factors for urinary tract stones. Clinical tests included urinalysis, tests for glomerular dysfunction, ultrasound, and biochemical markers. High melamine content in formula was significantly associated with urolithiasis — children fed high-melamine formula were seven times more likely to develop stones than those fed no-melamine formula. Most children with melamine-associated urinary stones did not have classic symptoms and signs, such as haematuria and white cells in urine. The authors advise that screening for urolithiasis should be based on the history of exposure to melamine, as symptoms may be non-specific or absent. N Engl J Med 2009; 360: 1067-1074 Maternal migraine Women who experience migraine in late pregnancy appear to be at higher risk of cardiovascular events, say US researchers. In a population-based sample of almost 34 000 post-partum women, diagnoses jointly associated with migraine at hospital discharge were assessed. Stroke, myocardial infarction, pulmonary embolus, hypertension, smoking, and diabetes were found to be related to migraine. In particular, peri-partum migraine was associated with a 17-fold increase in the risk of pregnancy-related stroke. The authors comment that the link between migraine and vascular disease in pregnancy is most likely due to the existence of overlapping pathophysiological mechanisms, combined with the physiological alterations of pregnancy. BMJ 2009; 338: b664 Folate in pregnancy Taking folic acid supplements during pregnancy may be associated with a slightly increased risk of wheeze and lower respiratory tract infection in infants, according to US and Norwegian researchers. In a study involving over 32 000 children born between 2000 and 2005, data were collected on the timing of folate and other vitamin supplementation in pregnancy, and wheezing and respiratory tract infection in children up to 18 months of age. Over 79% of mothers took folate supplements at some point during pregnancy. Women who took folate supplements were likely to be more educated, breastfeed for longer, and less likely to smoke. Wheeze and lower respiratory tract infections were most strongly associated with exposure to folic acid supplements in the first trimester of pregnancy. The authors postulate that the action of folate as a methyl donor may affect the fetus by epigenetic mechanisms influencing gene expression and phenotypes. They also caution that the effect measured was small, and that unmeasured confounding factors may be acting to influence this association. Arch Dis Child 2009; 94: 180-184 Legacy of Wittenoom Of the almost 3000 women and girls who lived at the blue asbestos mining and milling town of Wittenoom in Western Australia, 40 had died of malignant mesothelioma by the end of 2004. Australian researchers studying the outcomes for those living in the area between 1943 and 1992 have gone a step further and calculated the predicted mortality from mesothelioma for these women, who were either mine or mill workers, or residents. In the cohort of 2402 women remaining, the authors predict between 66 and 87 deaths up to 2030, with no decline in the number of deaths each year. The model that the researchers used to estimate future mortality included risks from other causes, time since first exposure, lag periods, and rates of clearance of crocidolite from the lungs. They comment that using rate of fibre clearance in the model avoids over-estimation of the predicted number of malignant mesotheliomas, a problem encountered in other studies. Occup Environ Med 2009; 66: 169-174 Absorbable stents The use of metallic drug-eluting coronary stents has been controversial because of the association with late stent thrombosis and difficulties with subsequent surgical revascularisation. Bioabsorbable everolimus-eluting stents may be a viable alternative, according to the results of a 2-year clinical follow-up of 29 patients treated with the stents. All participants had a single de-novo coronary artery lesion and were assessed using multiple imaging methods. After 2- years, the biodegradable stent had been absorbed and was incorporated into the vessel wall in all patients. No stent thrombosis occurred and the device appeared safe, with no cardiac deaths and one myocardial infarction in participants. The authors of the small study, which was funded by the stent manufacturers, admit that, although promising, the research has limitations and that results should be interpreted as preliminary findings only. Lancet 2009; 373: 897-910

Tanya Grassi

Objectives: To estimate the prevalence of depression among older Australians with common medical morbidities, and to determine the association between poor physical health and depression in this age group.Design: Cross-sectional, postal questionnaire survey.Setting and participants: 20 183 community-dwelling adults aged 60 years and over, under the care of 383 general practitioners participating in the Depression and Early Prevention of Suicide in General Practice (DEPS-GP) project (conducted between 2005 and 2008; the data in this article were collected during the baseline phase of the study in 2005).Main outcome measures: Depressive symptoms (measured by the nine-item depression scale of the Patient Health Questionnaire), health status (measured by the 12-item Short Form Health Survey and a medical morbidity inventory), social support (measured by the subjective support subscale from the Duke Social Support Index), and demographic and lifestyle information.Results: 18 190 participants (90.1%) reported having at least one chronic physical health condition, while 1493 (7.1%) experienced clinically significant depression (3.1% major depressive syndrome; 4.0% other depressive syndrome). Most chronic physical illnesses were associated with increased odds of depression, and participants with numerous medical morbidities and a high level of functional impairment were three to four times more likely to have a depressive illness.Conclusions: Depression is more the exception than the rule in later life, and among those who are medically unwell, the level of associated impairment may determine their risk of depression more than their acquired physical illness. Many of the factors associated with depression in medically ill patients are amenable to treatment, and GPs are in a unique position to address this important public health issue.

Jon J Pfaff PhD, MSc · Brian M Draper MD, FRANZCP · Jane E Pirkis PhD, MPsych · Nigel P Stocks MD, FRACGP · John A Snowdon MD, FRANZCP · Moira G Sim MB BS, FRACGP, FAChAM · Gerard J Byrne PhD, FRANZCP · Nicola T Lautenschlager MD, FRANZCP · Leon A Flicker PhD, FRACP · Ngaire M Kerse PhD, FRNZCGP · Robert D Goldney MD, FRANZCP · Osvaldo P Almeida PhD, FRANZCP

Objective: To describe the natural history and risk of early chronic kidney disease (CKD) in Indigenous Australian populations.Design, setting and participants: A prospective cohort of 2266 Aboriginal and non-Aboriginal children enrolled from primary schools throughout New South Wales from February 2002 to June 2004 and followed for 4 years.Main outcome measures: Urinalysis, height, weight, blood pressure, birthweight and sociodemographic status at baseline and 2- and 4-year follow-up; CKD risk factors: haematuria, albuminuria, obesity, and systolic and diastolic hypertension.Results: 2266 children (55% Aboriginal; 51% male; mean age, 8.9 years [SD, 2.0 years]) were enrolled at baseline. 1432 children (63%) were retested at 2-year follow-up, and 1506 children (67%) at 4-year follow-up. Prevalence of baseline CKD risk factors was frequent (2%–7%), but most abnormalities were transient. Besides persistent obesity (5.0%), persistence of CKD risk factors at final follow-up was low: haematuria (1.9%), albuminuria (2.4%), systolic hypertension (1.5%) and diastolic hypertension (0.2%). There was no difference in prevalence of persistent CKD risk factors between Aboriginal and non-Aboriginal children.Conclusions: Over 4 years of follow-up, Indigenous Australian children had no increased risk for early evidence of CKD. More than 70% of baseline risk factors were transient, and persistent risk factors were uncommon. Our findings suggest the increased risk for end-stage kidney disease seen in Indigenous adults is not yet manifest in these schoolchildren, and may be potentially preventable.

Leigh Haysom MB BS, MClinEpi, FRACP · Rita Williams BA · Elisabeth M Hodson MB BS, FRACP · Pamela A Lopez-Vargas BN, BSc, BHSc(TCM) · Leslie P Roy MB BS, MD, FRACP · David M Lyle MB BS, PhD, FAFPHM · Jonathan C Craig MB BS, PhD, FRACP

Objective: To determine whether the proportion of babies born large for gestational age (LGA) in New South Wales has increased, and to identify possible reasons for any increase.Design and setting: Population-based study using data obtained from the NSW Midwives Data Collection, a legislated surveillance system of all births in NSW.Participants: All 1 273 924 live-born singletons delivered at term (≥ 37 complete weeks’ gestation) in NSW from 1990 to 2005.Main outcome measures: LGA, defined as > 90th centile for sex and gestational age using 1991–1994 Australian centile charts; maternal factors associated with LGA were assessed using logistic regression.Results: The proportion of babies born LGA increased from 9.2% to 10.8% (18% increase) for male infants and from 9.1% to 11.0% (21% increase) for female infants. The mean birthweight increased by 23 g for boys and 25 g for girls over the study period. Increasing maternal age, higher rates of gestational diabetes and a decline in smoking contributed significantly to these increases, but did not fully explain them.Conclusions: There is an increasing trend in the proportion of babies born LGA, which is only partly attributable to decreasing maternal smoking, increasing maternal age and increasing gestational diabetes.

Ruth M Hadfield BSc, GCBiostat, DPhil(Oxon) · Samantha J Lain BComm, BHlthSci(Hons), MPH · Judy M Simpson PhD, CStat · Jane B Ford BA(Hons), PhD · Camille H Raynes-Greenow BA, MPH, PhD · Jonathan M Morris MM, FRANZCOG, PhD · Christine L Roberts MB BS, DipObs(RACOG), DrPH