MEDICAL UPDATES
By Associate Professor Jack Gerschman

LINKING SNOW AND GASTRO

MOUNTAINEERING can be a health hazard.

The increasing popularity of climbing and trekking means that fragile alpine environments are being contaminated by faecal waste that is causing high rates of gastrointestinal illness.

A recent study found one in three climbers suffered gastrointestinal problems while scaling North America's highest peak, Mt McKinley, in Alaska.

While pit latrines were being used at the base camps of many popular climbing spots world-wide problems arose with waste disposal higher up the mountain.

The correct protocol was for waste to be dropped into a crevasse or bagged up and hauled off the mountain.

But, according to researchers, climbers frequently chose the quick easy option of defecating directly into the snow (Wilderness and Environmental Medicine 2005;16:92-96).

"High winds spread faecal particles on to the top layers of snow, which is the water source for climbers," they said. The survey found that 40% of climbers had seen snow contaminated with faeces near camps. But only a minority boiled or purified it - rather than just melting it - before consumption. With alpine trekking growing in popularity, gastro outbreaks would become more common, the researchers warned.

Reassurance for chronic headache sufferers

PATIENTS with a history of chronic headaches can be reassured they are unlikely to be at an increased risk of subarachnoid haemorrhage, new Australian research has revealed.

A study found no evidence that recurrent migraine-like headaches even when the headaches were severe and confined to one side, were a risk factor for rupture of intracerebral aneurysms.

The researchers said these important results could be used not only to guide clinicians in the diagnosis of subarachnoid haemorrhage and predisposing factors for subarachnoid haemorrhage, but also in the counselling of patients.

"Patients, families and caregivers … often seek explanations for this devastating illness and may be concerned about the significance of past and ongoing headaches."

The researchers evaluated the history, frequency and characteristics of headaches in 432 patients living in Adelaide, Hobart, Perth and Auckland. All had experienced a subarachnoid haemorrhage for the first time (J Clin Neurosci, online 22 June).

Almost three-quarters experienced a headache at the onset of subarachnoid haemorrhage, while nearly a quarter reported a recent severe, unexplained headache about five days prior to presentation.

However, when compared with the case controls, there were no differences in the frequency or the types of previous headaches between the two groups. Headache had occurred in about half of the patient populations studied.

The researchers said that, while the findings showed recurrent headaches did not predispose patients to an increased risk of rupture of intracerebral aneurysm, they were not totally unexpected given that migraines were no longer considered a primary vascular disorder.

The neurotransmitter mechanism that activated migraines was likely to be different from factors related to the formation and rupture of cerebral aneurysms, they said.

Low-dose aspirin has no effect on cancer risk

Hopes that low-dose aspirin might help prevent cancer appear to have been dashed, but the jury is still out on a possible role for high-dose aspirin or other NSAIDs, researchers say.

Low-dose aspirin use over an average of 10 years did not reduce total risk of cancer, according to a randomised controlled trial in almost 40,000 women reported in the Journal of the American Medical Association (6 July).

There was no reduction in risk for breast cancer, colorectal cancer or cancer at any other side, apart from a marginally significant reduction in lung cancer risk, the study found.

"The findings from the WHS [Women's Health Study] suggest that aspirin at a dose of 100mg every other day is not effective in reducing risk of cancer in healthy women, although a beneficial effect on lung cancer cannot be ruled out," the authors wrote.

Earlier observational studies had suggested significant risk reductions for a range of cancers, with the evidence of an aspirin benefit strongest for breast and colorectal cancers.

However, two randomised trials had failed to confirm the reduction in colorectal risk, the authors said, while theirs was the first randomised trial to assess aspirin's impact on breast cancer risk.

It was possible that other NSAIDs or higher-dose aspirin might have a protective effect because they were more potent inhibitors of COX-2 activity, they said.

Professor Alan Coates, CEO of the Cancer Council of Australia, said the study's findings were disappointing but chemoprevention was fairly low on the list when it came to cancer prevention strategies. "Cancer prevention doesn't come in a bottle," he said.

Diet, exercise, sun protection and giving up smoking were all more important preventive strategies, he said.
JAMA 2005;294:47-55.

Call to declare wine health benefits

A SYDNEY GP is campaigning to have labels on wine bottles declare the health benefits of drinking wine in moderation.

Currently Australian regulations ban health claims on food and alcohol products, but Dr Philip Norrie, owner of a boutique vineyard in the Hunter Valley NSW, has called for change.

The self-proclaimed "wine doctor" said that the tipple was the best preventive medicine on the market.

"Authorities are reviewing regulations that prevent foods from making health claims," he said. "A box of bran cereal might say that it is good for your digestive health. A bottle of wine should say 'Reduces the risk of heart attack'."

"Patients at my surgery know that I suggest [a glass of] wine instead of a hypnotic or a sedative for helping them sleep at night."

Studies have found benefits of wine include reduced risk of vascular disease, dementia, cancer, macular degenerative, stroke and diabetes.

Dr Norrie advocated regular wine consumption, comparing having a daily drink with taking a daily multivitamin. "What you have on day won't carry into the next," he said.