17 January 2005

What comes first?

The cannabis or the psychosis? European researchers have challenged the commonly held belief that people may start using cannabis because they are predisposed to psychosis. They surveyed 2500 young Germans, aged 14 to 24 years, once in 1995 and again, four years later, in 1999. A predisposition to psychosis, determined from a self-report symptom checklist, did not predict future cannabis use four years later. However, exposure to cannabis did increase the risk of psychotic symptoms later in life, especially in those with a predisposition to psychosis. Moreover, there was a dose-response relationship — the greater the cannabis use at baseline, the greater the risk of developing psychotic symptoms, independent of a predisposition to psychosis.

BMJ, doi:10.1136/bmj.38267.664086.63 (published 1 Dec 2004)

Doctors in films

Patients' expectations of doctors may be adversely affected by the current negative movie portrayals of doctors, says a US author. Flores, an associate professor of paediatrics, epidemiology and health policy, reviewed over 130 films depicting doctors, made over eight decades. Until the 1960s, doctors were mostly seen as compassionate and idealistic individuals, but since then movie doctors have been more likely to be portrayed as greedy, egotistical, uncaring and unethical. Flores does not suggest we counter this by joining forces with Hollywood to produce a film that shows doctors not as gods or demons but as people just trying to do the best they can. However, he does put The Doctor at the top of his list of movies that may be useful in medical education. Made in 1991 and starring William Hurt, Flores says the movie is about a hotshot surgeon with a detached demeanour who learns about empathy and compassion when he contracts cancer.

Arch Dis Child 2004; 89: 1084-1088

Look into the future

When it comes to postoperative care, some patients may be just as happy to see their surgeon on screen — via a robotic telerounding visit (see figure) — as in person. Ellison and colleagues compared this procedure with standard ward round-type visits and a web-based video-conferencing system (involving laptop computers) in a randomised trial involving 85 patients who had undergone elective, short-stay, minimally invasive urological surgery. The "robot" arm of the study was assessed just as favourably by patients, and rated particularly well with regard to physician availability. Safety was not assessed.

J Am Coll Surg 2004; 199: 523-530

Slimming slumber

Some welcome news for our patients and the one or two of us who are overweight and not keen on exercising — chronic sleep curtailment may be a previously unrecognised risk factor for obesity. In a small, crossover study involving a dozen healthy young men, two nights of sleep restriction (four hours of sleep) led to increased hunger and appetite compared with two nights of sleep extension (10 hours). There were corresponding changes in circulating hormone levels — a drop in leptin (anorexigenic) and an increase in ghrelin (orexigenic).

Ann Intern Med 2004; 141: 846-850

Stop the super-spreaders

Ever wished there were more ways to slow down, if not stop, the rapid spread of airborne diseases like influenza and SARS? A small, international research study may show us the way forward. Edwards and colleagues explored their study hypothesis — that it might be possible to reduce the amount of aerosols we exhale by altering lung airway surface properties — by administering nebulised isotonic saline to 11 healthy adult volunteers. They found that the number of particles exhaled varied dramatically among the subjects. About half the group were "high-producers", and in these individuals, but not the others, nebulised saline led to a decrease in the number of particles exhaled.

Proc Natl Acad Sci U S A 2004; 101: 17383-17388

All’s well that ends well

In 1993, Australian researchers reported in The Lancet the results of their randomised controlled trial involving about 3 000 pregnant mothers. They found that a routine policy of multiple scans in pregnancy (from 18 weeks' gestation onwards) did not improve pregnancy outcomes over and above a single scan (at 18 weeks). However, they were concerned about an unexplained growth restriction in newborns whose mothers had been allocated to the repeated ultrasound group, and have followed the children involved in the study ever since. Now, they are pleased to report that, after 8 years of follow-up, there has been no adverse effect on long-term growth and development. However, the researchers caution that there is much more to learn before we can rest assured that ultrasound scanning in pregnancy is safe and without risk — today’s equipment is increasingly powerful and, moreover, scans may be conducted much earlier in pregnancy nowadays.

Lancet 2004; 364: 2038-2044

Dr Ann Gregory, MJA