Drop in temperature can raise risk of heart attack

THERE IS a strong connection between weather and health, according to a new study that shows that falling temperatures can increase the risk of heart attacks.

A fall of just one degree below the average daily temperature was shown to be sufficient to cause up to 200 extra heart attacks a day.

The number of people presenting with heart attacks increases whenever the temperature outside drops, according to a report by the London School of Hygiene and Tropical Medicine.

Researchers studied data from more than 84,000 hospital admissions in England and Wales and matched them up against daily temperatures from the British Atmospheric Data Centre.

They found that every one degree reduction in average daily temperature was associated with a 2 per cent increased risk of heart attack and the increased risk was cumulative if the temperature continued to fall below average.

This might seem a small risk but this would amount to an extra 200 heart attack patients a day across England and Wales, the authors said.

They found that the increased risk lasted for about 28 days and then tailed off, with the highest heart attack risk coming within the first two weeks after a temperature drop.

Those facing the greatest danger were older people between 75 and 84 and also people with previous coronary heart disease, according to the study which is published online this morning by the British Medical Journal (bmj.com).

People who took long-term, low-dose aspirin were at a slightly lesser risk, the researchers found.

Many earlier studies had shown that the outdoor temperature was linked to mortality risk over the short-term, with warm and cold extremes having an effect, the paper’s authors state.

Their study has now quantified the risk for “myocardial infarctions” (heart attacks) when the temperatures fall.

The results were adjusted to eliminate other factors such as air pollution, influenza activity and seasonality.

These findings showed the need to study the impact of higher temperatures on heart attack incidence given the threat of climate change, according to an accompanying editorial.

It also meant that clinicians should recognise exposure to high and low temperatures were risk factors in cardiovascular disease. They should be considered in terms of risk prevention, the editorial said.