People who spend more than four hours a day watching TV or playing video games are at higher risk of having a future cardiovascular event.
People who spend hours watching television, sitting in front of a computer screen or playing video games are more likely to suffer a cardiovascular event like a stroke or heart attack.
"The crucial finding from this study is that people spending in excess of four hours a day watching TV were at high risk of having a future cardiovascular event," says researcher Mark Hamer of University College London, adding there's also a higher risk of death whatever the cause.
Whether or not they use a computer at work, those who spent four hours of leisure time a day sitting at a computer or watching TV were about 50 percent more likely to die than those who spent less than two hours a day in front of a screen.
The researchers used data from 4,500 adults enrolled in an ongoing research program called the Scottish Health Survey.
Researchers accounted for other risk factors, such as smoking and high blood pressure.
"The important aspect of this finding is that we adjusted our analysis for a number of other risk factors - in particular, levels of physical activity that people were taking," says Hamer.
This latest study is generally consistent with previous research by others, which suggests that long periods of sitting are associated with heart attacks and related conditions. Hamer acknowledges that many people do have to spend all day at their computers, and many enjoy relaxing with their favorite TV program or game.
"But I think that what's really harmful is prolonged sitting, and so maybe a simple way to reduce this would be simply to take more breaks in the day and actually get up from your desk and it may be a matter of taking a five-minutes walk just to get your circulation moving again."
The study by Mark Hamer, lead author Emmanuel Stamatakis and others is published in the Journal of the American College of Cardiology.
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