Psychotropic Polypharmacy for the Treatment of Bipolar Disorder in Taiwan

Objective: Psychotropic polypharmacy in the treatment of bipolar disorder has proliferated. Yet evidence about the prevalence and predictors of different combinations of polypharmacy in inpatient settings is scarce. Methods: The Nationwide Psychiatric Inpatient Medical Claims (2000-2007) in Taiwan were used to examine prescriptions for mood stabilizers, antipsychotics, and antidepressants among recently discharged patients with bipolar disorder (N=5,449; 51% women, mean +/- SD age=36.8 +/- 12.4). Results: A total of 71% of prescriptions involved between-class polypharmacy, and 17% involved within-class polypharmacy. Patients older than 50 and patients at medical centers (>500 beds) were less likely to receive polypharmacy. Lower prescribed doses predicted polypharmacy. Receiving polypharmacy was not associated with a higher rate of readmission within one year. Conclusions: There was substantial use of various forms of polypharmacy in the treatment of inpatients with bipolar disorder. Randomized studies should be used to compare the cost-effectiveness of common psychotropic combinations and monotherapy to treat bipolar disorder.