Medication adherence among recipients with chronic diseases enrolled in a state Medicaid program

Limited information is currently available about medication adherence for common chronic conditions among the Medicaid population. The primary objective of this study was to assess medication adherence among Medicaid recipients with depression, diabetes, epilepsy, hypercholesterolemia, and hypertension. Factors influencing adherence were determined. The authors also assessed whether adherence influences the utilization of acute care services. The target population included nonelderly adult recipients (ages 21-64 years) who were continuously enrolled in the Mississippi (MS) Medicaid fee-for-service program from January 1, 2006 to December 31, 2007. Recipients were identified who had a medical services claim with a diagnosis of depression, diabetes, epilepsy, hypercholesterolemia, or hypertension in calendar year 2006. Within each chronic disease sample, medication adherence was determined using calendar year 2007 data for recipients who met inclusion and exclusion criteria. Recipients with adherence ≥80% were classified as adherent. Logistic regression analyses were used to determine the factors that predict medication adherence and the effect of adherence on concurrent all-cause acute care service (ie, hospitalization, emergency room visit) utilization. Approximately 24% of recipients with depression, 35.9% with diabetes, 53.6% with epilepsy, 32% with hypercholesterolemia, and 42.2% with hypertension were adherent. Within each chronic disease sample, males and whites had higher adherence than females and blacks. After controlling for demographic and disease-related covariates, recipients who were adherent had lower concurrent acute care service utilization than nonadherent recipients. Given the inverse relationship between adherence and acute care service utilization, policy makers should consider implementing educational interventions aimed at improving adherence in this underprivileged population.