20 October 2003

Practical peak

A peak expiratory flow rate (PEFR) — alone (ie, without spirometry) — is good for detecting patients with chronic obstructive pulmonary disease (COPD) in the community, according to UK researchers. Data from a cross-sectional national survey of 3874 adults aged 50–90 years found that a PEFR of less than 80% detected more than 90% of the subjects with COPD, including all of those with moderate or severe disease. Although sensitive for COPD, it was not as specific; however, many of the false positive results were in smokers.

BMJ 2003; 327: 653-654

Smokescreen

Children and adolescents appear to have easy access to tobacco products via the Internet, say US authors. In their study, four adolescents (under adult supervision) were able to buy cigarettes from 90% of 55 vendors' websites located in 12 states. Although most of the sites had posted an age warning on their web-site and the adolescents lied about their age when making their orders, no age verification was sought for any of the deliveries.

Although there is a variety of state legislation relating to cigarette sales to minors, there is no federal legislation in the USA that bans Internet and mail order tobacco sales to minors. More than half of the web-sites implicated in this study were located on Indian reservations, and tribal sellers have, in the past, claimed exemption from state laws because of sovereignty.

JAMA 2003; 290: 1356-1359

Anaphylaxis again and again

A Canberra allergy expert says that in any year, one in 12 patients who have suffered anaphylaxis will experience a recurrence and that one in 4 of these events will be severe. Professor Mullins had gained follow-up data for 304 patients who had been referred with anaphylaxis, finding that the best predictor of serious recurrence was the presence of serious symptoms on initial presentation. Although accidental ingestion of peanuts or tree nuts caused the largest number of relapses, the highest risk of any recurrence was associated with wheat and/or exercise sensitivity.

Clin Exp Allergy 2003; 33: 1033-1040

Moving target

In patients with nonvalvular atrial fibrillation who are at high risk for stroke, the target INR with warfarin should be set at a minimum of 2.0, aiming for an optimum of perhaps 2.5, say US researchers. Their advice is based on findings from their cohort study of 13 559 patients: anticoagulation with an INR set at 2.0 or more not only nearly halved the frequency of stroke but also reduced the severity and risk of death from stroke. The risk of serious haemorrhage was low until the INR was 4.0 or more.

N Engl J Med 2003; 349: 1019-1026

Getting a life . . . or a mortgage?

Traditional factors in the career choices young doctors make, such as remuneration and prestige, are being outgunned by lifestyle concerns in the USA.1 The specialties that senior medical students have sought to enter over the six years from 1996 to 2002 seem to reflect an increasing interest in having control over the hours worked per week and adequate time for leisure, family and other pursuits. In workforce terms, disciplines like anaesthetics and dermatology are winners, while positions in general practice, and even general surgery, remain unfilled.

Meanwhile, in some parts of Canada medical students are graduating with debts of more than $100 000.2 Looking more like mortgages than student loans, these debts come courtesy of rising tuition fees, reduced government support, the replacement of grants with loans and an increasing reliance on lines of credit to cover living costs while studying. There is anecdotal evidence that career choices are being affected, with one graduate asking, "Is a career in public health going to be lucrative enough to pay off a 6-figure debt?"

1. JAMA 2003; 290: 1173-1178
2. CMAJ 2003; 169: 457-458

Women's health initiative

Brisk walking for between 75 to 150 minutes a week will reduce the risk of breast cancer in postmenopausal women by about 18% when compared with inactive women, according to the US Women's Health Initiative (WHI) Cohort study. This study analysed data from 74 171 women aged between 50 and 79 years, of whom 1780 had breast cancer newly diagnosed over nearly 5 years of follow-up. The beneficial effect was even greater in those who exercised for longer durations; it was seen particularly in women who were of normal weight.

The WHI study has previously found that in postmenopausal women the risks of hormone replacement therapy include breast cancer.

JAMA 2003; 290: 1331-1336

— Dr Ann Gregory, MJA