LONDON, Ontario, Sept. 28 (UPI) -- Increased levels of job strain and a lack of social support at work are associated with higher risk of depression -- a study of Canadian workers found.

Emma K. Robertson Blackmore of the University of Rochester Medical Center, in New York and Canadian researchers utilized data from the Canadian Community Health Survey, a population-based survey of 24,324 employed, community-dwelling individuals conducted in 2002.

The researchers also assessed the prevalence of lifetime and 12-month depressive episodes and psychosocial work stress.

The study, published in the American Journal of Public Health, showed increased levels of job strain were significantly associated with an increased risk of major depressive episodes among men. A similar, but statistically insignificant, trend was also seen among women. However, for both genders, a lack of social support at work was significantly related to depression.

"Depression in the workplace is a major public health problem that requires intervention yet remains under recognized and under treated," the study authors said in a statement.