Do medical homes increase medication adherence for persons with multiple chronic conditions?

Abstract

Medications are an integral component of management for many chronic conditions, and suboptimal adherence limits medication effectiveness among persons with multiple chronic conditions (MCC). Medical homes may provide a mechanism for increasing adherence among persons with MCC, thereby enhancing management of chronic conditions. To examine the association between medical home enrollment and adherence to newly initiated medications among Medicaid enrollees with MCC. Retrospective cohort study comparing Community Care of North Carolina medical home enrollees to nonenrollees using merged North Carolina Medicaid claims data (fiscal years 2008-2010). Among North Carolina Medicaid-enrolled adults with MCC, we created separate longitudinal cohorts of new users of antidepressants (N=9303), antihypertensive agents (N=12,595), oral diabetic agents (N=6409), and statins (N=9263). Outcomes were the proportion of days covered (PDC) on treatment medication each month for 12 months and a dichotomous measure of adherence (PDC>0.80). Our primary analysis utilized person-level fixed effects models. Sensitivity analyses included propensity score and person-level random-effect models. Compared with nonenrollees, medical home enrollees exhibited higher PDC by 4.7, 6.0, 4.8, and 5.1 percentage points for depression, hypertension, diabetes, and hyperlipidemia, respectively (P's<0.001). The dichotomous adherence measure showed similar increases, with absolute differences of 4.1, 4.5, 3.5, and 4.6 percentage points, respectively (P's<0.001). Among Medicaid enrollees with MCC, adherence to new medications is greater for those enrolled in medical homes.