Background: Studies have shown that the economic consequence of relapse is costly and found to be six times higher than maintenance costs.
Objective: Estimate the probability of relapse in patients diagnosed with schizophrenia treated with paliperidone palmitate long-acting injection (PP) or oral atypical antipsychotic (OAT). Methods: This preliminary analysis used data from REACH OUT, a naturalistic, observational study of adult schizophrenia patients receiving atypical antipsychotic treatment in community behavioral health organizations. Health resource utilization data collected at 6-months post-baseline were analyzed. The number of relapse events (NRE) was defined as the total number of psychiatric or all-cause hospitalizations, visits to emergency departments (ED), crisis centers, and assertive community treatment. An indicator for relapse was defined if NRE>0. A supplemental control group analysis employing propensity matching technique was used. A logistic regression modeled the probability of relapse and the mean NRE was estimated using Poisson regression. Wilxocon-Rank Sum test tested the differences in probabilities and mean NRE between PP and OAT.
Results: The final matched dataset of 354 PP to OAT patients showed the cohorts were comparable in baseline demographics, inpatient admissions (P=0.413), and ED visits (P=0.430). In the 6-months follow-up period, a significantly lower probability of relapse was observed in PP vs OAT patients (0.29 vs 0.41; P<0.001). The estimated mean number of relapse was significantly lower in PP vs OAT (1.34 vs 1.49; P<0.001). No adjustment for multiplicity was made.
Conclusions: Preliminary results suggest a potential long-term benefit from PP based on reduced probability of relapse and mean NRE.