eMJA: In other journals - 3 February 2003

AAA screening vindicated

All men should have a single ultrasound at age 65 to screen for abdominal aortic aneurysm, says an editorial¹ commenting on the recent MASS study.^{2, 3} The Multicentre Aneurysm Screening Study randomised nearly 70 000 British men, inviting half to have a screening ultrasound. Eighty per cent (27 147) accepted; 1333 aneurysms were detected and then monitored or repaired. Follow-up was for a mean of four years, in which time there were 65 aneurysm-related deaths in the invited group (including 22 men who had been invited but had not accepted) compared with 113 among controls, giving a risk reduction of 42%. 710 men needed to be screened to prevent one death. The cost-effectiveness ratio at 10 years was estimated to be £8000 per quality-adjusted life-year gained, well under the threshold for acceptability in Britain's National Health Service.

1. BMJ 2002; 325:1123-1124

2. BMJ 2002; 325:1135-1138

3. Lancet 2002; 360: 1531-1539

Sun, serotonin and SAD

Melbourne researchers have shown that sunlight increases brain serotonergic activity, which thus may contribute to mood seasonality and seasonal affective disorder. They measured neurotransmitter levels in 101 volunteers, in blood obtained from a high internal jugular vein catheter (to directly sample venous blood from the brain) and from a central arterial catheter, and related the levels to detailed meteorological data. Brain serotonin turnover was lowest in winter. Serotonin production was directly related to the duration of bright sunlight and varied acutely with luminosity: median 395 pmol/min on bright days, compared with 49 pmol/min on dull days. There was no seasonal variation in extracerebral serotonin turnover, nor in cerebral turnover of norepinephrine or dopamine.

Lancet 2002; 360: 1840-1842

Steroids for meningitis

European investigators advise that adults with bacterial meningitis should be given adjunctive dexamethasone (10 mg qid for 4 days) to improve their outcome. The rationale is based on animal studies which have shown that the subarachnoid space inflammatory response is a major factor contributing to morbidity and mortality. Dexamethasone attenuates this response. In a randomised placebo-controlled trial of 301 patients, those given dexamethasone (in addition to antibiotics) were less likely to have a poor outcome (15% v 25%) or to die (7% v 15%) than controls. The effect was most apparent in patients with pneumococcal meningitis. No effect was seen on neurological sequelae such as hearing loss.

N Engl J Med 2002; 347: 1549-1546

Window to the lungs?

Topical β-blockers given for glaucoma are known to exacerbate bronchospasm in patients with chronic obstructive pulmonary disease or asthma, but a recent study suggests that it's not just those with known respiratory problems who are at risk. British researchers used the Mediplus database to identify 2645 people without a history of respiratory disease who were first exposed to topical β-blockers between 1993 and 1997, and compared their subsequent diagnoses of respiratory problems with those of 9094 matched controls. In the year after commencing therapy the exposed patients were 2.29 times more likely than the unexposed patients to be given, for the first time, a drug used in the treatment of reversible airways obstruction. This was equivalent to a number needed to harm of only 55 patients.

BMJ 2002; 325: 1396-1397

A caution on preventers

Amid growing concern about adrenal suppression in people taking high doses of inhaled corticosteroids for asthma, researchers have attempted a survey of adrenal crises associated with these medications in the United Kingdom. Surveys were sent to all paediatricians and endocrinologists in the UK, and those who identified a potential case completed a detailed questionnaire. Thirty-seven episodes in 33 patients (28 children and five adults) were identified. Most children presented with altered consciousness or coma associated with acute hypoglycaemia, whereas adults generally experienced a more insidious onset. Thirty patients had been treated with fluticasone (mean daily doses of 980 µg in children and 1380 µg in adults). Of interest was the finding that fluticasone was the drug used in 91% of cases, yet it accounted for less than 20% of all prescriptions for inhaled steroids in the UK in 1998. The authors postulated that this might relate to its high lipophilicity, allowing entry into the blood via the lungs, without first-pass hepatic metabolism. They suggested great caution in using doses of more than 400 µg/day of fluticasone in children and 1000 µg/day in adults.

Arch Dis Child 2002: 87: 457-461