No one wants to talk about employees and their mental health, but there's a business issue at stake: lost productivity, according to a new study, due to one out of every 40 workers possibly being affected by depression.

Findings are based on an analysis of depression-related short-term disability claims among nearly 63,000 workers employed by three major Canadian companies.

About three percent of the employees had taken short-term disability leave at least once because of a mental health problem, and 2.5 percent of them had one or more leaves of absence that were depression-related, it was reported in the July issue of the Journal of Occupational and Environmental Medicine.

Overall, at least 144,700 workdays were lost due to depression-related short-term disability among the study participants, amounting to a loss of roughly $20.5 million in productivity, the report indicates.

What's more, these workers remained on disability for about 95 days, almost one month longer than workers on disability for other types of mental health problems.

About 12 percent of employees on short-term depression-related disability had reportedly experienced at least one other episode of short-term disability during the previous year that was related to a mental health problem.

In contrast, less than ten percent of employees on leave due to some non-depression-related mental health cause had a previous episode of short-term disability in the past year.

Still, about three quarters of the workers on depression-related short-term leave returned to work rather than quitting, retiring or taking long-term disability, the study notes. Women, who were more likely to be on short-term disability for depression-related reasons, were also more likely to return to work afterwards. Men were more likely to quit, retire or stop working.