The study is particularly significant at a time when the Canadian economy continues to face uncertainty. Mental illness costs the Canadian economy an estimated $51 billion annually, with a third of that attributed to productivity losses.

Published in the current issue of the Canadian Journal of Psychiatry, the study examined data from a large-scale community survey of employed and recently employed people in Alberta.

People who experienced a depressive episode were significantly less likely to be highly productive, the study showed. "We expected this, as past research has found that depression has adverse effects on comprehension, social participation, and day-to-day-functioning," said Dr. Carolyn Dewa, Head of CAMH's Centre for Research on Employment and Workplace Health and lead author.

"What's exciting is we found that treatment for depression improves work productivity. People who had experienced a moderate depressive episode and received treatment were 2.5 times more likely to be highly productive compared with those who had no treatment," she says. "Likewise, people who experienced severe depression were seven times more likely to be high-performing than those who had no treatment."

Of the 3000 workers looked at in the sample, 8.5 per cent experienced a depressive episode, representing 255 workers.

Though the results showed the effectiveness of treatment on work and performance, the data also showed a troubling trend. "We found that among all study participants who had been diagnosed with a severe depressive episode, 57 per cent did not receive treatment; 40 per cent of those who experienced a moderate depressive episode did not receive treatment," said Dr. Dewa. "When we look at the success of workers in the sample who received treatment while still in the workplace, it really speaks to the importance of prevention and the need for employers to facilitate treatment and support. If people are able to receive treatment early, disability leave, which costs companies $18,000 per leave, may be avoided."

"Stigma and discrimination have often affected people's willingness to access services, as has the lack of knowledge around supports available in the workplace," added Dr. Dewa. "It is crucial that employers offer mental health interventions to their employees and support them in engaging in treatment, as well as continuing to support them as they transition back into the workplace."

The data for this analysis was collected by the Institute for Health Economics, Alberta.

Note: If no author is given, the source is cited instead.

• Workplace Health
• Mental Health Research

• Depression
• Mental Health

• Industrial Relations
• Scientific Conduct

• Postpartum depression
• Seasonal affective disorder
• Dementia
• Illusion of control
• Psychopathology
• Antidepressant