Men in middle and upper social classes who experience psychological stress at work are about one and a half times more likely than others to have a stroke, according to a new study published in the Journal of Occupational and Environmental Medicine. About 10 percent of strokes among this group of men can be attributed to stress at work, the study noted.

Researchers examined data collected on 5,000 men, ages 40 to 59, living in Copenhagen. The 30-year study began in 1970 and consisted of physical exams and interviews regarding alcohol consumption, smoking habits, work stress, and whether they were treated for diabetes. The men were grouped according to five social classes (based on education level and job position). Men with a history of heart disease or a heart attack were not included in the study.

During the course of the study, 779 men had a stroke and 167 died from a stroke.

Men in the top three social classes were 38 percent more likely to have a stroke than men with little or no stress on the job. No link was found between work stress and strokes for men in the lower two social classes – although this may be due to less work stress for these groups, researchers noted.