Work stress triggers heart disease and diabetes

Led by Dr Tarani Chandola, the study builds on previous supposed connections between chronic work-related stress and heart disease, although evidence of the biological processes was unclear until now. The findings have been published online by the British Medical Journal (BMJ).

The research team examined the association between work-related stress and the metabolic syndrome - a cluster of factors that increase the risk of heart disease and type-two diabetes - in 10,308 British civil servants aged between 35 and 55 over a 14-year period. This research was part of the larger Whitehall II Study, which was set up in 1985 to determine what underlies the social gradient in death and disease in men and women.

Work stress was measured on four occasions between 1985 and 1999. Components of the metabolic syndrome, such as obesity, high blood pressure, and high cholesterol levels, were measured between 1997 and 1999. Social position and health damaging behaviours, such as smoking, heavy alcohol consumption, and no exercise, were also recorded. Even after these other risk factors were taken into account, a strong relationship was found between stress and metabolic syndrome. Men with chronic work stress were nearly twice more likely to develop the syndrome than those with no exposure to work stress. Women with chronic work stress were also more likely to have the syndrome, but they formed a small group.

Both men and women from lower employment grades were more likely to have the syndrome, confirming previous reports that the syndrome has a social gradient.

The association between the metabolic syndrome and exposure to health damaging behaviours was stronger among men than women. Poor diet, smoking, heavy alcohol consumption, and physical inactivity were all associated with higher odds of the syndrome.

Dr Chandola said: "One possible explanation is that prolonged exposure to work stress may affect the nervous system. Alternatively, chronic stress may reduce biological resilience and thus disturb the body's physiological balance."

• Links:
• UCL Epidemiology and Public Health
• BMJ
• Whitehall II