Utilization of health care services following Georgia Medicaid's 2004 policy change for the atypical antipsychotics

Background: In 2004 the Georgia Medicaid program implemented a prior-authorization policy for atypical antipsychotic drugs resulting in an average savings of $2.7 million per year. The objective of this study was to determine if implementation of this program significantly impacted healthcare utilization in the Georgia Medicaid Program. Research Design: Single-cohort, observational study utilizing segmented regression and time series analysis. The population of interest was continuously eligible, adult Georgia Medicaid recipients with a schizophrenia diagnosis and use of an atypical antipsychotic during the study period (final N = 12,210). Outcomes: Healthcare services utilization: emergency room visits, outpatient office visits, hospital admissions and length of stay during the study period. Analysis of a non-continuously eligible population was also performed, where applicable, to investigate disenrollment bias in study results. Results: Significant models were identified for emergency room visits and hospital admissions. A significant decline in post-policy trend for the average number of emergency room visits (absolute difference = -0.042 per member per month; relative difference = -20.92%) and the average number of hospital admissions per member per month (absolute difference = -0.010 per member per month; relative difference = -22.27%) was observed at the end of the study period. Significant models were not identified for outpatient visits or length of stay. Conclusions: To the extent that medical utilization reflects patient health outcomes and health status, the results of this study indicate this prior authorization program has potentially improved the health of schizophrenic patients in Georgia while lowering program costs.