Relationship between patient socio-demographic characteristics and discontinuance of olanzapine following a new prior authorization requirement in Florida's Medicaid Program

Objective: A priority of Healthy People 2010 is eliminating health disparities. Using a sample of Medicaid enrollees 18 to 64 years old, we examined whether there were age, race or gender disparities in discontinuance of olanzapine following a new prior authorization (PA) requirement for this drug

Methods: Medicaid claims data were used to examine the relationship between patient socio-demographic characteristics and the discontinuance of olanzapine following the PA policy change. We compared patient characteristics of those participants who discontinued olanzapine prior to the PA change to characteristics related to discontinuation at the time of the PA requirement.

Results: Prior to the date of preauthorization implementation, 16% of people taking olanzapine discontinued the medication within the following two months. In comparison, subsequent to implementation of the PA policy 62% of patients discontinued the medication within the following two months. Logistic regression was used to compare factors related to discontinuing olanzapine prior to preauthorization requirements to discontinuances under the new policy. Compared to the prior period, individuals who were 34 years old or older (p<.0001), females (p=.0421), Hispanics (p=.0010), and those on the medication for a shorter period of time (p<.0001) were more likely to discontinue olanzapine. The implications of these findings are important for future policy decisions.