Severity of mood symptoms and work productivity in people treated for bipolar disorder

Objective: To evaluate the relationship between mood symptoms and work productivity in people with bipolar disorder. Methods: A total of 441 outpatients treated for bipolar disorder were enrolled from mental health clinics of a health plan in Washington State. A baseline assessment included confirmation of diagnosis (using the Structured Clinical Interview for DSM-IV) as well as assessment of employment status, functional impairment, and days missed from work. Eight follow-up interviews over 24 months included self-reported employment status, self-reported days missed from work due to illness, and assessment of current and interval mood symptoms using the Longitudinal Interval Follow-up Examination. Results: Averaged over four assessments, patients with current major depression were 15% less likely to be employed than those without significant depressive symptoms [odds ratio (OR) = 0.84, 95% confidence interval (CI): 0.76-0.92]. Manic or hypomanic symptoms were not significantly associated with probability of employment (OR = 0.93, CI: 0.83-1.04). Among those employed, major depression was associated with 4.06 additional days of work missed per month (CI: 1.05-7.06) compared to those without significant depressive symptoms. Meeting criteria for manic or hypomanic episode was associated with a similar number of missed work days, but this difference was not statistically significant (adjusted difference = 4.11 days, CI: -0.18-8.40). Conclusions: Among patients with bipolar disorder, depression is strongly and consistently associated with decreased probability of employment and more days missed from work due to illness. Symptoms of mania or hypomania have more variable effects on work productivity.