Study links overtime to depression

May 15, 2012

Study links overtime to depressionIf you regularly work more than 11 hours a day, you could be twice as likely to experience a major depression compared to a colleague who works seven to eight hours a day. So says a British study that examined the careers of 2,000 middle-aged British civil servants. None of the employees showed signs of depression when the study began.

Researchers followed the civil servants for an average of 5.8 years. After adjusting the data for socio-demographic factors, lifestyle (e.g., smoking, alcohol use), job strain and social support at work, the researchers found a 2.3 to 2.5 times greater risk of a major depression for regular overtime workers compared to peers working standard hours. Workers were more likely to have a major depression if they were younger, female, lower in occupational grade, had a chronic physical disease, and used alcohol moderately.

The researchers noted that positive work characteristics, such as high control or high rewards, may protect an employee against the adverse health effects of long working hours. On the other hand, they said, working long hours may also mean higher exposure to poor working conditions.

The researchers warn that “plausible explanations of why long working hours are associated with the development of depression cannot be drawn directly from our study.” It’s possible that long working hours may affect mental health in part through factors they didn’t measure, they said, such as work-family conflicts, difficulties in unwinding after work, or prolonged increased cortisol levels.

The study, “Overtime Work as a Predictor of Major Depressive Episode: A 5-Year Follow-Up of the Whitehall II Study,” was published in PLoS ONE, an international, peer-reviewed online journal. View the full article.

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