Treatment patterns and Medicaid spending in comorbid schizophrenia populations: once-monthly paliperidone palmitate versus oral atypical antipsychotics

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