Short-Term Impact of Preferred Drug List Changes on Health Care Use and Medicaid Costs: Injectable Risperidone

Abstract

This study assessed short-term effects of the removal of injectable risperidone long-acting therapy from the Florida Medicaid preferred drug list (PDL) in April 2006. A difference-in-difference approach was used to contrast changes (60 days pre and post) in health care utilization and costs of Medicaid recipients who were receiving risperidone long-acting therapy when the policy was changed (N=247) and of a matched sample who received risperidone long-acting therapy in April 2005 (non-PDL, N=247). The policy change was associated with increased acute care events. Whereas acute care events declined for the non-PDL group, involuntary commitments and total acute care events increased for the PDL group, as did expenditures for crisis-related events. Medicaid pharmacy costs fell for both groups, but total expenditures did not decline significantly for the PDL group. The PDL restriction was associated with increased acute care events and did not reduce short-term Medicaid program expenditures.