Depression in the workforce: the intermediary effect of medical comorbidity

It is amply documented that mood disorders adversely affect job satisfaction, workforce productivity, and absenteeism/presenteeism. It is also well documented that mood disorders are an independent risk factor for several chronic medical disorders (e.g., obesity, diabetes mellitus, cardiovascular disease). Emerging evidence indicates that the workforce dysfunction associated with depression is partially mediated by medical comorbidity.

We conducted a PubMed search of all English-language articles published between 2005 and July 2009 with the following search terms: major depressive disorder and depression, cross-referenced with work productivity, disability, economic cost, absenteeism, presenteeism, and medical comorbidity. Articles selected for review were based on adequacy of sample size, the use of standardized experimental procedures, validated assessment measures, and overall manuscript quality.

Mood disorders are the most impairing condition amongst working adults. It is estimated that approximately 35-50% of employees with depression will take short-term disability leave at some point during their job tenure. Moreover, 15-20% of the workforce will receive short-term disability benefits during any given year; the annual income of individuals affected by depression is reduced by approximately 10% when compared to unaffected employees. Chronic stress-sensitive conditions independently contribute to workforce maladjustment and associated disability. The mood disorder population is differentially affected by several stress-related medical conditions resulting in greater impairment in the workforce.

Disability modelling in the depressed employee has emphasized the complex interrelationship between depressive symptoms, workforce stress, and consequent disability. A more refined model must include the effects of chronic medical conditions as a powerful mediator and/or moderator of workforce impairment. Multidisciplinary interventions have been demonstrated to reduce, but not eliminate workforce disability related to depression, underscoring the need for elucidating other modifiable factors. Screening, treatment, and prevention initiatives need to target chronic medical conditions in depressed employees in order to reduce overall workforce disability.