Long-term effectiveness and cost of a systematic care program for bipolar disorder

Abstract

Context: Despite the availability of efficacious treatments, the long-term course of bipolar disorder is often unfavorable.

Objective: To test the effectiveness of a multicomponent intervention program to improve the quality of care and long-term outcomes for persons with bipolar disorder.

Design: Randomized controlled trial with allocation concealment and blinded outcome assessment.

Setting: Mental health clinics of a group-model prepaid health plan.

Patients: Of 785 patients in treatment for bipolar disorder who were invited to participate, 509 attended an evaluation appointment, 450 were found eligible to participate, and 441 enrolled in the trial.

Interventions: Participants were randomly assigned to a multicomponent intervention program or to continued care as usual. Three nurse care managers provided a 2-year systematic intervention program, including the following: a structured group psychoeducational program, monthly telephone monitoring of mood symptoms and medication adherence, feedback to treating mental health providers, facilitation of appropriate follow-up care, and as-needed outreach and crisis intervention.

Main outcome measures: In-person blinded research interviews every 3 months assessed mood symptoms using the Longitudinal Interval Follow-up Examination. Health plan administrative records were used to assess the use and cost of mental health services.

Results: Intent-to-treat analyses demonstrated that the intervention significantly reduced the mean level of mania symptoms (z = 2.09, P = .04) and the time with significant mania symptoms (19.2 vs 24.7 weeks; F(1) = 6.0, P = .01). There was no significant intervention effect on mean level of depressive symptoms (z = 0.19, P = .85) or time with significant depressive symptoms (47.6 vs 50.7 weeks; F(1) = 0.56, P = .45). Benefits of the intervention were found only in a subgroup of 343 persons with clinically significant mood symptoms at the baseline assessment. The incremental cost (adjusted) of the intervention was 1251 dollars (95% confidence interval, 55-2446 dollars), including approximately 800 dollars for the intervention program services and an approximate 500 dollars increase in the costs of other mental health services.

Conclusions: Population-based systematic care programs can significantly reduce the frequency and severity of mania in bipolar disorder, and cost increases are modest considering the clinical gains. The incorporation of more specific cognitive and behavioral content or more effective medication regimens may be necessary to significantly reduce the symptoms of depression.