www.safetyandhealthmagazine.com/articles/working-overtime-is-bad-for-the-heart-study-2

Working overtime is bad for the heart: study

May 20, 2010

Working 10 hours or more a day may increase a person's risk for heart problems, suggests research from the University College London and the Finnish Institute of Occupational Health in Helsinki.

An 11-year study of 6,014 British civil servants found that compared with people who did not work overtime, those who worked three or more hours longer than a seven-hour day had a 60 percent higher risk of heart-related problems such as heart disease, nonfatal heart attacks and angina, according to a press release from the European Society of Cardiology. The society, based in Sophia Antipolis, France, publishes European Heart Journal, in which the study appeared.

Researchers gave several possible reasons for the correlation: Overtime was associated with Type A behavior, psychological distress, lack of sleep and not taking enough time to unwind before bed. Chronic stress, "hidden" high blood pressure and overtime workers being more likely to work while ill also could be factors, the release said.

The findings are part of the Whitehall II study, which has been tracking British worker health since 1985. The research appeared in the May 11 online edition of European Heart Journal.