Evaluation of the Safer Use of Antipsychotics in Youth (SUAY) Study on Population Level Antipsychotic Initiation: An Interrupted Time Series Analysis

Background: Atypical antipsychotics carry a high risk profile and may be prescribed for youth with conditions where other first line treatments are more appropriate. This study aimed to evaluate the population-level effectiveness of the Safer Use of Antipsychotics in Youth (SUAY) intervention, which aimed to reduce inappropriate atypical antipsychotic prescribing. Methods: We conducted an interrupted time series analysis using segmented regression to measure changes in prescribing trends of antipsychotic initiation rates pre- and post- SUAY intervention at four U.S. health systems between 2013 and 2020. Results: In our overall model, adjusted for age and insurance type, antipsychotic initiation rates decreased by 0.73 (95% CI: 0.30, 1.16) prescriptions per 10,000 person months before the SUAY intervention. In the first quarter following the intervention, there was an immediate decrease in the rate of antipsychotic initiations of 6.57 (95% CI: 0.99, 12.15) prescriptions per 10,000 person months. When comparing the post-intervention period to the pre-intervention period, there was an increase of 1.09 (95% CI: 0.32, 1.85) prescriptions per 10,000 person months, but the increasing rate in the post-intervention period alone was not statistically significant (0.36 prescriptions per 10,000 person months, 95% CI: -0.27, 0.99). Conclusion: Further analyses are needed to confirm these unexpected results. The declining trend of antipsychotic initiation seen between 2013 and 2018 (pre-SUAY intervention) may have naturally reached a level at which prescribing was clinically warranted and appropriate, resulting in the rate leveling out. The COVID-19 pandemic, which began in the final three quarters of the post-intervention period, may also have increased antipsychotic medication initiation.