A Comparison of Long-Acting Injectable Antipsychotics with Oral Antipsychotics on Time to Rehospitalization within One Year of Discharge in Elderly Patients with Schizophrenia

Abstract Objective The effectiveness of long-acting injectable antipsychotics (LAIs) in elderly patients with schizophrenia remains unclear. This study aimed to compare the effect of LAIs with oral antipsychotics (OAPs) on time to rehospitalization within one year of discharge in this population. Other factors potentially associated with time to rehospitalization and trends in LAI prescription rates during the study period were also investigated. Methods Patients over 60 years of age with schizophrenia discharged between 2006 and 2017 were followed for one year under naturalistic conditions. Survival analysis was used in the comparison between LAIs and OAPs regarding time to rehospitalization. Covariates thought to affect time to rehospitalization were also analyzed. The Cochran-Armitage trend test was used to evaluate whether a time trend existed for LAI prescription rates. Results The LAIs group had a significantly lower rehospitalization rate and a significantly longer time to rehospitalization within one year of discharge than the OAPs group. Other factors that were associated with a longer time to rehospitalization included a shorter index hospitalization during the time of the study and fewer previous hospitalizations. No significant time trend was found for LAI prescription rates during the study period. However, the prescription rate of second-generation LAIs grew significantly. Conclusions LAIs were found superior to OAPs in preventing rehospitalization. A continuous increase in second-generation LAI prescription rate may be due to the better side-effect profile of second-generation LAIs compared to first-generation LAIs. More studies investigating the effectiveness of LAIs in elderly patients with schizophrenia are needed in the future.