Abstract
Objective: To compare treatment patterns and Medicaid spending between schizophrenia patients initiating once-monthly paliperidone palmitate (PP1M) and oral atypical antipsychotics (OAAs) within four comorbid populations: cardiovascular disease (CVD), diabetes, hypertension and obesity.
Methods: Five-state Medicaid data identified comorbid adults with schizophrenia initiating PP1M or OAAs (index) from September 2009 balanced with inverse probability of treatment weighting. Chi-squared and t-tests compared index antipsychotic (AP) exposure (no gap >90 days) duration, AP polypharmacy, and index AP adherence (proportion of days covered ≥80%) and persistence (no gap ≥60 days) at 12 months post-index. Linear models with a non-parametric bootstrap procedure compared costs.
Results: PP1M patients consistently had longer index AP exposure (e.g. CVD: 244 vs. 189 days; p < .001) and less AP polypharmacy (e.g. CVD: 21.1% vs. 28.1%; p < .001) versus OAA patients. Relative to OAA patients, adherence was more likely in PP1M patients with CVD or obesity (e.g. CVD: 28.6% vs. 22.1%; p < .001) and less likely for patients with diabetes (22.0% vs. 24.4%; p = .031). Persistence was consistently more likely for PP1M versus OAA patients (e.g. CVD: 49.9% vs. 27.4%; p < .001). Total costs were not significantly different between PP1M and OAA patients for any comorbidity. PP1M patients with diabetes, hypertension or obesity had higher pharmacy and lower medical costs (all p < .05).
Conclusions: Treatment with PP1M versus OAAs may reduce AP polypharmacy and increase AP persistence in comorbid patients with schizophrenia, without increasing total healthcare costs. Comorbidities are a highly prevalent driver of excess mortality in this vulnerable population; thus, future studies should specifically address the real-world effectiveness of therapies, including long acting injectable therapies (LAIs), for these patients.
Transparency
Declaration of funding
This research was funded by Janssen Scientific Affairs LLC.
Author contributions: Analyses were carried out by R.K., D.P., P.L. and B.E. All authors participated in the conception and design of the study and the interpretation of data, and all approve the final manuscript for publication.
Declaration of financial/other relationships
R.K., D.P., P.L. and B.E. have disclosed that they are employees of Analysis Group Inc., a consulting company that has received research grants from Janssen Scientific Affairs LLC, to conduct this study. K.J. has disclosed that she is an employee of Janssen Scientific Affairs LLC.
CMRO peer reviewers on this manuscript have received an honorarium from CMRO for their review work, but have no relevant financial or other relationships to disclose.
Acknowledgements
Writing assistance was kindly provided by Samuel Rochette and Federica Torres Sakai, both from Analysis Group Inc.
Previous presentation: Part of the material in this manuscript has been presented at the 28th American Psychiatric Association Annual Meeting, Atlanta, GA, USA, 14–18 May 2016