Collaborative care for bipolar disorder: Part II. Impact on clinical outcome, function, and costs

Abstract

Objective: The study addressed whether a collaborative model for chronic care, described in part I (this issue), improves outcome for bipolar disorder. Methods: The intervention was designed to improve outcome by enhancing patient self-management skills with group psychoeducation; providing clinician decision support with simplified practice guidelines; and improving access to care, continuity of care, and information flow via nurse care coordinators. In an effectiveness design veterans with bipolar disorder at 11 Veterans Affairs hospitals were randomly assigned to three years of care in the intervention or continued usual care. Blinded clinical and functional measures were obtained every eight weeks. Intention-to-treat analysis (N=306) with mixed-effects models addressed the hypothesis that improvements would accrue over three years, consistent with social learning theory. Results: The intervention significantly reduced weeks in affective episode, primarily mania. Broad-based improvements were demonstrated in social role function, mental quality of life, and treatment satisfaction. Reductions in mean manic and depressive symptoms were not significant. The intervention was cost-neutral while achieving a net reduction of 6.2 weeks in affective episode. Conclusions: Collaborative chronic care models can improve some long-term clinical outcomes for bipolar disorder. Functional and quality-of-life benefits also were demonstrated, with most benefits accruing in years 2 and 3.