Time to Discontinuation of Depot and Oral First-Generation Antipsychotics in the Usual Care of Schizophrenia

OBJECTIVE: This study compared the time to discontinuation for any reason of first-generation antipsychotics--in oral versus depot formulation--in the usual care of schizophrenia. METHODS: This study used data from a three-year, prospective, nonrandomized, noninterventional, multisite study of schizophrenia. Participants initiated on oral haloperidol or fluphenazine (N=202) were compared with those initiated on haloperidol or fluphenazine in depot formulation (N=97) on time to all-cause discontinuation for one year after initiation, by using Kaplan-Meier survival analysis, a Cox proportional hazards regression model, and propensity score-adjusted bootstrap resampling methods. RESULTS: Compared with participants treated with the oral formulation, those treated with depot first-generation antipsychotics had a significantly longer mean time to all-cause medication discontinuation and were twice as likely to stay on the medication. CONCLUSION: In the usual care of schizophrenia, treatment with first-generation antipsychotics in depot formulation appears to be associated with longer time to all-cause medication discontinuation compared with oral formulation of the same medication.