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Cold weather increases heart attack risk

A new study has warned that cold weather could increase the risk of heart attacks, with people in the 75-84 age group appearing to be more vulnerable than others.

The study concluded that every 1C drop in temperature is associated with around 200 extra cases of heart attack across the country.

According to the research, reported in the the British Medical Journal, people who have suffered from heart disease in their past are also vulnerable, while those taking aspirin are less susceptible.

On the other hand, the study found that increases in temperature do not raise the risk of heart attacks. This, however, might be because the country does not usually experience very hot weather.

The study was conducted by a group of experts from the London School of Hygiene and Tropical Medicine. The researchers examined data for 84,010 hospital admissions for heart attacks in England and Wales in 2003 to 2006.

Factors such as air pollution, flu rates, seasonal patterns and long-term trends were taken into consideration while conducting the study.

The scientists found a 1C fall in the average daily temperature was associated with a cumulative 2% increase in the risk of heart attacks for 28 days.

They noted that even a small increase in the risk translated into "substantial absolute numbers" of extra heart attacks.

People in the UK suffer an estimated 146,000 heart attacks a year, equivalent to an average of 11,600 in a 29-day period.

Ellen Mason, Senior Cardiac Nurse at the British Heart Foundation, said: "Although the increased risk is small, if there is a nationwide drop in average temperature it could equate to a significant number of heart attacks each day.

"This timely piece of research reminds us that older people and anyone with heart disease should keep warm in their homes after the summer draws to a close."

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British Medical Journal