SOURCES: Yuli Huang, M.D., department of cardiology, Southern Medical University, Guangzhou, China; Jennifer Majersik, M.D., associate professor, neurology, University of Utah, School of Medicine, Salt Lake City; Oct. 14, 2015, Neurology, online
WEDNESDAY, Oct. 14, 2015 (HealthDay News) -- Having a high-stress job, particularly one that is demanding but offers little personal control, may raise the risk for a stroke, Chinese researchers report.
An analysis of six previously published studies from several countries included nearly 140,000 people who were followed for up to 17 years. It found those with high-stress jobs had a 22 percent higher risk of stroke than those with low-stress jobs. Among women, the increased risk was even higher -- 33 percent, the researchers reported.
"Many mechanisms may be involved in the association between high-stress jobs and the risk of stroke," said lead researcher Dr. Yuli Huang, from the department of cardiology at Southern Medical University in Guangzhou.
Most important, high-stress jobs may lead to unhealthy behaviors, such as poor eating habits, smoking and a lack of exercise, Huang said.
"It is vital for people with high-stress occupations to address these lifestyle issues," said Huang.
The report was published online Oct. 14 in the journal Neurology.
The studies that Huang's team analyzed included one in the United States, three in Sweden, one in Japan and one in Finland.
Huang and colleagues grouped jobs into four categories based on how much control workers had over their job and how hard they worked or the psychological demands of the job. The categories included passive jobs, low-stress jobs, high-stress jobs and active jobs.
Job factors included time pressure, mental demands and coordination burdens. Physical labor and total number of hours worked were not included.
Those with passive jobs included janitors, miners and other manual laborers, who had little demand and little control. Low-stress jobs included scientists and architects, who had low demand and high control, according to the study.
High-stress jobs, which have high demand and low control, included waitresses, nursing aides and other service industry workers. People with active jobs, like doctors, teachers and engineers, had high demand and high control, the researchers said.
People in high-stress jobs were 58 percent more likely to have a stroke caused by a blood clot in the brain -- an ischemic stroke -- than those with low-stress jobs. Those with passive and active jobs did not have any increased risk of stroke, Huang said.
The researchers said that more than 4 percent of overall stroke risk was caused by high-stress jobs. For women, however, high-stress jobs increased that risk to 6.5 percent.
The study has some limitations, the researchers noted. First, job stress was measured only once in the original studies. Second, other risk factors for stroke, such as high blood pressure or high cholesterol, were not accounted for in the original studies.
Dr. Jennifer Majersik, an associate professor of neurology at the University of Utah School of Medicine in Salt Lake City, and author of an accompanying journal editorial, said the study "shows what people have thought for a long time -- that certain kinds of stress cause negative effects on health."
Previous studies have shown a connection between work stress and heart disease, but this is the first research to show that association for stroke, she said.
However, the new study did not prove a cause-and-effect relationship between work stress and stroke.
Majersik thinks that lowering the risk of stroke may mean having more control over your work.
"There are ways in your workplace to increase control," she said. These might include flexible hours and more power to make decisions. "These may not work, but I'd love to see them tried," Majersik said.
In addition, people can change jobs to find one where they have more control, she said.
"I view job stress as another modifiable risk factor," Majersik said. "We don't yet know what to do about it. But I counsel my patients that this is something they should look at."
Patients often ask if stress caused their stroke, Majersik said. "I haven't known what to say, now I feel I can say, 'You know, maybe.' "
Visit the U.S. National Library of Medicine for more on stroke.