Objective: Depression symptom severity, the most commonly studied outcome in antidepressant treatment trials, accounts for only a small portion of burden related to major depression. While lost work productivity is the biggest contributor to depression's economic burden, few studies have systematically evaluated the independent effect of treatment on work productivity and the relationship between changes in work productivity and longer-term clinical course.
Method: Work productivity was measured repeatedly by the Work Productivity and Activity Impairment self-report questionnaire in 331 employed participants with major depression enrolled in the Combining Medications to Enhance Depression Outcomes trial. Trajectories of change in work productivity during the first 6 weeks of treatment were identified and used to predict remission at 3 and 7 months.
Results: Participants reported reduced absence from work and increased work productivity with antidepressant treatment even after controlling for changes in depression severity. Three distinct trajectories of changes in work productivity were identified: 1) robust early improvement (24%), 2) minimal change (49%), and 3) high-impairment slight reduction (27%). Compared with other participants, those with robust improvement had 3-5 times higher remission rates at 3 months and 2-5 times higher remission rates at 7 months, even after controlling for select baseline variables and remission status at week 6.
Conclusions: In this secondary analysis, self-reported work productivity improved in depressed patients with antidepressant treatment even after accounting for depressive symptom reduction. Early improvement in work productivity is associated with much higher remission rates after 3 and 7 months of treatment.