Effectiveness comparison of antipsychotics used in first-episode psychosis: A naturalistic cohort study

Abstract

Introduction: Several studies have explored comparative effectiveness of first prescribed antipsychotics for FEP using time to treatment discontinuation as a proxy measure. Consistent differences are not demonstrated. We explored this in a large clinical sample across different services. We present an interim data analysis. Method: A retrospective cohort study examined the naturalistic treatment of all patients accepted by FEP services across 6 sites in Sussex and Warwickshire over 3 years. Case notes were examined to the point of any-cause discontinuation up to 1 year. Median and mean survival times and rate of discontinuation at 1 year were compared using survival analysis. Results: Of 579 patients prescribed antipsychotic treatment, data were available for 451. Aripiprazole was prescribed in 59 cases, Olanzapine 184, Quetiapine 114 and Risperidone 80 cases. Greatest risk of treatment discontinuation was in the first 3 months for all medications. Risperidone had the longest median time-to-discontinuation (175 days, 95%CI 47.90- 302.09), followed by Aripiprazole (162 days, 95%CI 43.72-280.27), Quetiapine (154 days, 95%CI 81.68-226.32) and Olanzapine (112 days, 95%CI 85.90-138.10). Patients prescribed Olanzapine had highest rates of discontinuation by 1 year (76.4%), followed by Aripiprazole (69.5%), Quetiapine (67.9%) and Risperidone (65.8%). Discontinuation rates for patients prescribed Risperidone versus Olanzapine were significantly different (%, = 3.125; p = 0.0386). Conclusions: Risperidone appears more effective than Olanzapine in the treatment of FEP, where time to all-cause treatment discontinuation is considered. In the light of the greater metabolic influence of Olanzapine, its use as a first line antipsychotic in FEP patients needs further consideration