Study: Long work hours can increase risk of stroke by up to 45 percent

Clocking long hours at work might earn you bonus points with your boss, but new research shows that it could also increase your risk of stroke up to 45 percent, especially for those under the age of 50.

Researchers at the American Heart Association found that people who work long hours — particularly those who have been working long hours for 10 years or more — are at significantly higher risk of stroke.

“Working long hours” was defined as working more than 10 hours in a day on at least 50 days out of the year — that’s approximately one 10-hour day a week.

AHA researchers pulled data from a French population-based epidemiological research group called CONSTANCES, which provided information on the age, sex, smoking habits and work hours of 143,592 participants. Additional medical interviews were conducted to gather information about prior stroke occurrences and cardiovascular risk factors.

All participants were within the ages of 18-69, and those who had previously suffered strokes before regularly working long hours and those with part-time employment were excluded from the study.

Researchers found that 29 percent (45,542) of participants worked long hours, and 10 percent (14,481) of participants worked long hours for at least 10 years. Of the total 143,592 participants, 1,224 suffered strokes.

That means that participants who worked long hours were 29 percent more likely to suffer a stroke, and those who worked long hours for 10 years or more were 45 percent more likely to suffer a stroke.

“The association between 10 years of long work hours and stroke seemed stronger for people under the age of 50,” said study author Alexis Descatha, M.D., Ph.D., a researcher at Paris Hospital, Versailles and Angers University and at the French National Institute of Health and Medical Research, but more research is necessary to fully explain this connection.

Some prior studies suggest that long work hours affect people differently depending on profession. These studies found that business owners, CEOs, farmers and managers were less affected by long work hours, which the AHA hypothesizes has something to do with being able to make more of their own decisions and to exert more control in the workplace.

Increased risk of stroke isn’t the only negative side effect of overworking. In 2004, the CDC compiled data from 52 then-recent studies on overworking and published a report on their findings.

In 16 of 22 studies addressing general health effects, overtime was associated with poorer perceived general health, increased injury rates, more illnesses, or increased mortality. One meta-analysis of long work hours suggested a possible weak relationship with preterm birth. Overtime was associated with unhealthy weight gain in two studies, increased alcohol use in two of three studies, increased smoking in one of two studies, and poorer neuropsychological test performance in one study.

Those are steep costs for a handful of extra work hours each week that probably aren’t allowing you to get more work done anyway.Many studies have shown that, after a certain point, working longer hours does nothing to boost productivity and can even be detrimental to workers’ output.