Association of antipsychotic treatment switching in patients with schizophrenia, bipolar, and major depressive disorders

Abstract

Aims: To evaluate the association of relapse and healthcare resource utilization in patients with schizophrenia (SZ), bipolar disorder (BD), or major depressive disorder (MDD) who switched antipsychotic medication versus those who did not.

Materials and methods: Medicaid claims from six US states spanning six years were retrospectively analyzed for antipsychotic switching versus non-switching. For all patients with SZ, BD, or MDD, and for the subset of patients who also had ≥1 extrapyramidal symptoms (EPS) diagnosis at baseline, times to the following outcomes were analyzed: underlying disease relapse, other psychiatric relapse, all-cause emergency room (ER) visit, all-cause inpatient (IP) admission, and EPS diagnosis.

Results: Switchers (N = 10,548) had a shorter time to disease relapse, other psychiatric relapse, IP admissions, ER visits, and EPS diagnosis (all, log-rank p < .001) than non-switchers (N = 31,644). Switchers reached the median for IP admission (21.50 months) vs non-switchers (not reached) and for ER visits (switchers, 9.07 months; non-switchers, 13.35 months). For disease relapse, other psychiatric relapse, and EPS diagnosis, <50% of patients had an event during the two-year study period. Subgroup analysis of those with ≥1 EPS diagnosis revealed similar associations.

Limitations: Only association, not causation, may be inferred, and there may be differences between the patient groups in parameters not evaluated.

Conclusions: These results show that disease and other psychiatric relapse, all-cause ER visits, IP admissions, and EPS diagnosis occurred earlier for patients who switched antipsychotics than for those who did not, suggesting that switching is associated with an increased risk of relapse in patients with SZ, BD, and MDD. This may be attributed to more-severely ill patients being less responsive than those with less-severe illness, which, in turn, may require more episodes of switching.

Keywords:

• Schizophrenia
• bipolar disorder
• major depressive disorder
• tardive dyskinesia
• antipsychotic
• medicaid claims database

Transparency

Declaration of funding

This study was funded by Teva Pharmaceuticals, Petach Tikva, Israel.

Declaration of financial/other relationships

Benjamin Carroll: Employee of Teva Branded Pharmaceutical Products R&D, Inc.

Rajeev Ayyagari: Employee of Analysis Group, Inc.

Darren Thomason: Employee of Analysis Group, Inc.

Fan Mu: Employee of Analysis Group, Inc.

Michael Philbin: Employee of Teva Pharmaceuticals, Field Medical.

Author contributions

BC: Conception and design; analysis and interpretation of the data; drafting of the paper and revising it critically for intellectual content; final approval of the version to be published

RA: Conception and design; analysis and interpretation of the data; drafting of the paper and revising it critically for intellectual content; final approval of the version to be published

DT: Conception and design; analysis and interpretation of the data; drafting of the paper and revising it critically for intellectual content; final approval of the version to be published

FM: Conception and design; analysis and interpretation of the data; drafting of the paper and revising it critically for intellectual content; final approval of the version to be published

MP: Conception and design; revising manuscript critically for intellectual content; final approval of the version to be published

Acknowledgements

We thank Dana Meyen, PhD (Chameleon Communications International with funding from Teva Pharmaceuticals) for editorial assistance in the preparation of this report.