Stressful, long working hours, along with heart disease and diabetes can be a deadly mix for men, according to a new study published online June 5 in The Lancet Diabetes & Endocrinology.
For the study of more than 100,000 adults, researchers identified published studies through a systematic review of PubMed and Embase from inception to August 20, 2014. They obtained unpublished data for 20 cohort studies from the Individual-Participant-Data Meta-analysis in Working Populations Consortium and open-access data archives. They used cumulative random-effects meta-analysis to combine effect estimates from published and unpublished data.
The researchers found a 1.7 times increased risk of death in men with pre-existing cardiometabolic disease—such as those with diabetes, coronary heart disease, or a history of stroke—and job strain, compared to those with cardiometabolic disease but no job strain. No such excess risk was seen in men free of cardiometabolic disease or in women.
In men with cardiometabolic disease, a greater mortality risk was associated with job strain and remained even when the men exercised, controlled their weight, cholesterol, and blood pressure, and did not smoke, according to the researchers.
“This suggests that the adverse effects of stress in vulnerable people cannot be mitigated simply by physical activity and maintaining a healthy weight,” says lead author Mika Kivimaki, chair of social epidemiology at University College London.
These findings suggest that more attention should be paid to the management of vascular risk factors in individuals who work long hours, according to the authors.
“So, just following a healthy lifestyle is not going to solve the problem. It is important that healthcare executives realize that some people are especially vulnerable to stress because of their pre-existing disease and think how that can be best managed,” Kivimaki says
The researchers did not find a similar link between work stress and mortality in women.
“The reasons for this sex difference are not known,” Kivimaki says. “One possibility is that work is a greater source of stress for men than women.”