A new British study finds that colder temperatures are followed by a spike in heart attacks. For every one-degree Celsius drop in temperature, relative risk of heart attacks increased by 2%; the higher incidence was seen for up to two weeks after the arrival of colder temperatures. Researchers analyzed data on 84,010 hospital admissions in 15 urban areas of England and Wales over four years, adjusting for a variety of other risk factors. People ages 75-84 and those with a history of coronary heart disease showed the strongest association between cold waves and heart attacks. The scientists suggested several possible ways in which cold might affect the body to help trigger a heart attack, if the association is causal. Cold weather causes responses in blood vessels that may increase the work required for the body to regulate temperature. Or the explanation could be behaviors connected with colder weather, such as shoveling snow, that boost heart-attack risk.TO LEARN MORE:BMJ, August 10, 2010; dx.doi. org/10.1136/bmj.c3823.
