Impact of late-to-refill reminder calls on medication adherence in the Medicare Part D population: evaluation of a randomized controlled study

OBJECTIVES This study evaluates a nationwide pharmacy chain's late-to-refill (LTR) reminder program that entails local pharmacists placing reminder calls to Medicare Part D patients. METHODS We conducted a randomized controlled study among 735,218 patients who exhibited nonadherent behavior by not refilling a maintenance medication 3 days from an expected refill date. Patients were randomly assigned to an intervention group who received LTR reminder calls or to a control group. We used Walgreens pharmaceutical claims data from 2015 to estimate the impact of LTR calls on short-term and annual adherence. RESULTS The initial refill rate within the first 14 days of the expected refill date significantly increased in the intervention group by 22.8% (6.09 percentage points) compared to the control group (P<0.001). The proportion of days covered (PDC) in the intervention group increased significantly by 1.5% (0.856 percentage points) relative to the control group (P<0.001) over 365 days. Patients in the intervention group were significantly more adherent (PDC ≥80%) by 3% (0.97 percentage points) compared to the control group (P<0.001). Over a 270-day follow-up period, persistence significantly increased by 2.15 days in the intervention group (P<0.001). CONCLUSION Results from this study suggest that LTR reminder calls increased adherence for Medicare Part D patients who are late in refilling their medications and therefore have the potential to reduce their risk for hospitalization and health care costs. Additionally, the intervention increased the number of patients with PDC ≥80% by ~3%, positively impacting Medicare Part D plan quality rating.