Among patients with first-episode schizophrenia in Japan, initiation of long-acting injectable (LAI) antipsychotics was extremely rare. Patterns of switching from oral medication to an LAI and of LAI initiation were identified for the first time using JMDC data.
A research group at Kyoto University longitudinally described patterns of LAI antipsychotic initiation in a cohort approximating patients with first-episode schizophrenia, using the JMDC claims database and covering the period from January 2005 to March 2024. The study included 24,226 patients, with a median follow-up of 30 months.
During the study period, only 437 patients, or 1.8% of the total, received an LAI at least once. The median time from diagnosis to the first LAI dispensing was 12 months, and the proportion receiving an LAI remained below 2% throughout the period.
Among patients who switched from oral medication to an LAI, the median PDC during the year before LAI initiation was 0.82, and 26.9% experienced hospitalization for medical care and protection during that period.
The authors interpret these findings as showing that LAI initiation was rare in the claims population of Japanese health insurance enrollees and was generally carried out after oral medication had been initiated. They state that the findings demonstrate the actual pattern of LAI initiation among patients with schizophrenia who had recently begun treatment.