What medical journals say about stroke

HEART VALVE LOWERS STROKE RISK

Heart Valves

A study found that a new, smaller transcatheter heart valve called Sapien 3, by Edwards, is associated with a lower risk of stroke and death than the older version.

High-risk patients who received the new-generation valve had a 1.54 per cent risk of stroke, compared with a 4.5 per cent risk reported for its predecessor. The risk of dying was 2.2 compared with 3.5 per cent.

Sapien, like similar devices, is used to help people with damaged aortic heart valves, a condition that leads to death in more than half of cases within two years.

AIR POLLUTION IS BAD NEWS

Air pollution

New research in the British Medical Journal suggests that short-term spikes in air pollution can lead to an increase in cases of stroke and stroke deaths, particularly in lower-income countries such as China.

University of Edinburgh researchers reached the conclusion after looking at relevant studies published to date. Their work builds on previous findings linking air pollution with heart disease and lung conditions, among others.

The researchers speculate that stroke may occur as a result of pollutants constricting or damaging blood vessels. The effect appears to be strongest for sulphur dioxide and weakest for ozone.

SLEEP LINKED TO STROKE?

Sleep

People who sleep more than eight hours a day may have a 46 per cent higher than average risk of having a stroke, according to a Cambridge University study of 10,000 volunteers, whose sleeping habits were followed for ten years.

The finding, published in the journal Neurology, does not prove that sleep causes stroke, say the study’s authors. Factors other than sleep may have played a role.

Additionally, the data on sleep were from self-reports, which can be unreliable. Sleeping too much could be an early symptom rather than a cause, they say. Further research is needed.