Spillover effects of state medicaid antipsychotic prior authorization policies in US commercially insured youth

To evaluate spillover effects of Medicaid antipsychotic prior authorization (PA) policies among commercially insured youth.

Commercially insured youth residing in nine US states that implemented PA exclusively for antipsychotics in 2011 or 2012 were identified using a 10% random sample of enrollees in the IQVIA PharMetrics Plus database spanning 2007 to 2015. Youth were included if they were ≤18 years, met the age criteria of the PA at the time of dispensing, and had at least 1 month of prescription drug coverage from 2007 to 2015. The primary outcome of interest was the monthly prevalence of antipsychotics. We implemented segmented regression of interrupted time series analysis to estimate changes in the monthly prevalence of targeted medications, overall and stratified by age. Trends were compared in the 4-year period before and the 3-year period after implementation of PA policies.

Antipsychotics prescribing significantly decreased 6.74/10 000 (95% CI, -9.04 to -4.44) enrollees per month immediately after PA implementation. However, PA was not associated with significant long-term trend changes (-0.06; 95% CI, -0.16 to 0.03). Antipsychotic prescribing in children <12 years-old significantly decreased 0.14/10 000 (95% CI, -0.21 to -0.07) enrollees per month after PA implementation, while prescribing in adolescents 12 to 18 years-old significantly increased 0.32/10 000 (95% CI, 0.16 to 0.47) enrollees per month.

While Medicaid PA polices for antipsychotic oversight did not affect overall prescribing, there were spillover effects in U.S. commercially insured children <12 years-old. This suggests that state-level Medicaid policies intended to improve the quality of care and safe use of antipsychotics can have broad reach.