Working Longer Hours Increases Risk of Stroke, Study Says

Working longer hours increases the risk of stroke, according to a new European study.

Physical inactivity, heavy drinking and a tendency to ignore symptoms of health problems could all be part of the reason that people who spend extra hours at the office had a 33 percent higher risk for cerebrovascular events, according tothe [1] study published this week by The Lancet [1].

“Our findings show that individuals who work 55 hours or more per week have a 1.3 times higher risk of incident stroke than those working standard hours,” the authors concluded. “Long working hours were also associated with incident coronary heart disease, but this association was weaker than that for stroke.”

The meta-analysis of 25 previous studies tracked 603,838 people, the authors wrote. They adjusted for self-reported factors such as smoking, alcohol, body mass index and other factors.

The longer working people had higher rates of strokes when they crunched the numbers, they said. They also found that people who from lower socioeconomic groupings also tended to have more strokes and were more likely to develop coronary heart disease – though the risk of the latter was only increased 13 percent, they added.

The 44 scientists listed as authors on the paper hypothesized that physical inactivity, a propensity for heavier alcohol consumption and even just a tendency to ignore healthy symptoms while at the desk could partially explain the linkage. However, the very pressure of being at work could be the main underlying cause.

“Sudden death from overwork is often caused by stroke and is believed to result from a repetitive triggering of the stress response,” they concluded.

“The pooling of all available studies on this topic allowed us to investigate the association between working hours and cardiovascular disease risk with greater precision than has previously been possible,” said Mika Kivimaki, the lead author, from University College London.

The study is the “strongest indication of a causal association” yet for cardiovascular consequences of working too much, according to an accompanying Lancet analysis published by Urban Janlert [2], an epidemiologist from Umea University in Sweden.

“Long working hours are not a negligible occurrence. Therefore, that the length of a working day is an important determinant mainly for stroke, but perhaps also for coronary heart disease, is an important finding,” he wrote.

“For now, we have a risk factor that could and should be the subject of general policy decisions,” Janlert added.