The mediational role of cognitive function on occupational outcomes in persons with major depressive and bipolar disorder

Abstract Background Improving functioning in adults with major depressive disorder (MDD) and bipolar disorder (BD) is a priority therapeutic objective. Methods This retrospective post hoc secondary analysis evaluated 108 patients with MDD or BD receiving the antidepressants vortioxetine, ketamine, or infliximab. The analysis aimed to determine if changes in objective or subjective cognitive function mediated the relationship between depression symptom severity and workplace outcomes. Cognitive function was measured by the Perceived Deficits Questionnaire (PDQ-5), the Digit Symbol Substitution Test (DSST), and the Trail Making Test Part B (TMT-B). Depression symptom severity was measured by the Montgomery–Åsberg Depression Rating Scale (MADRS). Workplace function was measured by the Sheehan Disability Scale (SDS) work–school item. Results When co-varying for BMI, age, and sex, the association between MADRS and SDS work scores was partially mediated by PDQ-5 total scores and DSST total scores, but not DSST error scores and TMT-B time. Limitations This study was insufficiently powered to perform sub-group analyses to identify distinctions between MDD and BD populations as well as between antidepressant agents. Conclusions These findings suggest that cognitive impairment in adults with MDD and BD is a critical mediator of workplace function and reinforces its importance as a therapeutic target.