Researchers questioned 143,592 adults 18 to 69 years old who had at least six months of work experience and predominantly full-time jobs about their typical work schedules. They also had physicians take detailed medical histories for each participant, including any history of stroke or risk factors for stroke, like diabetes, high blood pressure, or elevated cholesterol. Overall, 42,542 participants, or about 30 percent, reported working more than 10 hours daily for at least 50 days a year — which researchers defined as long working hours. And 14,481 people, or about 10 percent, reported at least a decade of long working hours. A total of 1,224 participants, or roughly 1 percent, had a stroke at some point after they started working long hours. Working long hours was associated with a 29 percent higher risk of stroke than working less than 10 hours a day, researchers reported. And when people worked long hours for a decade or more, they had a 45 percent higher risk of stroke. “We need to learn to slow down after 10 years,” says Alexis Descatha, MD, PhD, senior author of the study and a researcher at Paris Hospital, Versailles and Angers University and at the French National Institute of Health and Medical Research (Inserm). The study wasn’t a controlled experiment designed to prove whether or how long work hours might directly cause a stroke. But it’s possible stress from long hours played a role, and that a lack of free time for healthy lifestyle habits also contributed, Dr. Descatha says. “Long work hours, and the chronic stress associated with that, can accelerate natural aging,” says Joshua S. Yamamoto, MD, a cardiologist at Johns Hopkins Sibley Memorial Hospital in Washington, DC, who wasn’t involved in the study. High stress leads the body to produce more stress hormones like adrenaline. These hormones raise blood pressure, increase the work load on the heart, strain blood vessels, and increase the likelihood of irregular heartbeats known as atrial fibrillation that are a major cause of stroke, Dr. Yamamoto says. Having too many hours at work also leaves too little time for the healthy things we can do outside the office to help protect against stroke, Yamamoto added. Men and women had a similar increase in stroke risk with long work hours. Younger workers appeared especially vulnerable, however. People under 50 who worked long hours for at least a decade were more than twice as likely to have a stroke than their counterparts who worked less. The increased stroke risk for years of long hours was just 36 percent for people over 50. People in positions of authority at work may also be less susceptible to strokes with long hours than workers without much control over their schedules or job duties. Business owners, executives, and managers in the study who worked long hours for a decade or more had a 21 percent higher risk of stroke, the study found. The increased risk shot up to 59 percent for blue collar workers and 70 percent for people with low-skilled white collar jobs. “People working in highly demanding jobs — low control jobs or working long hours — are under continuous stress and the effects will show on the body in the long term,” says Pouran D. Faghri, MD, director of the Center for Environmental Health and Health Promotion at the University of Connecticut in Storrs. We can’t all quit our jobs and still pay our bills. But we can minimize the risk of stroke associated with long hours by getting a good night’s sleep, eating a healthy breakfast, and taking as many breaks as possible during the day to stretch our legs or meditate in a quiet place, Dr. Faghri says.
