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January 18, 2011

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Exercise may not outweigh health effects of “couch potato” recreation

Jan. 12, 2011
Courtesy of the American College of Cardiology 
and World Science staff

Spend­ing too much lei­sure time in front of a TV or com­put­er screen ap­pears to dra­mat­ic­ally in­crease the risk for heart dis­ease and prem­a­ture death from any cause, per­haps re­gard­less of how much ex­er­cise one gets, ac­cord­ing to a new stu­dy.

The anal­y­sis found that peo­ple who spend more than four hours daily on screen-based en­ter­tain­ment like TV, com­put­er or vi­deogames are more than twice as likely to have a “ma­jor car­di­ac event” in­volv­ing hos­pi­tal­iz­a­tion, death or both com­pared to peo­ple who spend less than two hours on such ac­ti­vi­ties.

Spend­ing too much lei­sure time in front of a TV or com­put­er screen ap­pears to dra­mat­ic­ally in­crease the risk for heart dis­ease and prem­a­ture death from any cause, per­haps re­gard­less of how much ex­er­cise one gets, ac­cord­ing to a new stu­dy. (Im­age cour­tesy U.S. Nat'l Lib­rary of Med­i­cine)

Spending too much leisure time in front of a TV or computer screen appears to dramatically increase the risk for heart disease and premature death from any cause, perhaps regardless of how much exercise one gets, according to a new study The analysis found that people who spend more than four hours daily on screen-based entertainment like TV, computer or video games, are more than twice as likely to have a “major cardiac event” involving hospitalization, death or both than people who spend less than two hours daily on such activities. The research is published in the Jan. 18 issue of the Journal of the American College of Cardiology. Billed as the first study to examine the association between screen time and non-fatal as well as fatal cardiovascular events, it also suggests metabolic factors and inflammation may partly explain the link between prolonged sitting and the risks to heart health. “People who spend excessive amounts of time in front of a screen — primarily watching TV — are more likely to die of any cause and suffer heart-related problems,” said Emmanuel Stamatakis of University College London, who led the research. “Our analysis suggests that two or more hours of screen time each day may place someone at greater risk for a cardiac event.” Compared with those spending less than two hours a day on screen-based entertainment, the study found a 48% increased risk of all-cause mortality in those spending four or more hours a day and a roughly 125% increase in risk of cardiovascular events in those spending two or more hours a day. These associations were independent of traditional risk factors such as smoking, hypertension, excess weight, social class, as well as exercise. The findings have prompted authors to advocate for public health guidelines that expressly address “recreational sitting” especially as a majority of working age adults spend long periods being inactive while commuting or being slouched over a desk or computer. “It is all a matter of habit. Many of us have learned to go back home, turn the TV set on and sit down for several hours – it’s convenient and easy to do. But doing so is bad for the heart and our health in general,” said Stamatakis. “And according to what we know so far, these health risks may not be mitigated by exercise, a finding that underscores the urgent need for public health recommendations to include guidelines for limiting recreational sitting and other sedentary behaviors, in addition to improving physical activity.” Stamatakis said the next step will be to try to uncover what prolonged sitting does to the human body in the short- and long-term, whether and how exercise can mitigate these consequences, and how to alter lifestyles to reduce sitting and increase movement and exercise. The study included 4,512 adults who were respondents of the 2003 Scottish Health Survey, a representative, household-based survey, researchers said. A total of 325 all-cause deaths and 215 cardiac events occurred during an average of 4.3 years of follow up. Measurement of “screen time” included self-reported TV and DVD watching, video gaming, as well as leisure-time computer use. Authors also included multiple measures to rule out the possibility that ill people spend more time in front of the screen as opposed to other way around. Authors excluded those who reported a previous cardiovascular event and those who died during the first two years of follow up just in case their underlying disease might have forced them to stay indoors and watch TV more often. Stamatakis and his team also adjusted analyses for indicators of poor health, such as diabetes and hypertension.