Abstract
BACKGROUND: Hypertension, hyperlipidemia, and type 2 diabetes (T2D) are 3 of the most common chronic conditions, but related medication adherence rates are far below 80%. Consequences of poor adherence include high health care utilization/costs and increased mortality. There is accumulating evidence in support of the benefits of affording pharmacists the opportunity to practice at the full scope of their licensure by engaging in patients' clinical care. OBJECTIVE: To examine the impact of a large national pharmacy chain's pharmacist-led interventions to improve medication adherence among older adults with hypertension, hyperlipidemia, or T2D. A secondary objective was to estimate the potential cost savings associated with improved adherence. METHODS: Participants were Medicare patients aged 18 years or older who had 2 or more prescription fills in at least 1 of the 3 therapeutic classes. The primary outcome, optimal adherence, was defined as proportion of days covered (PDC) of 80% or higher. A difference-in-differences (DID) design with a generalized linear model analytical approach was applied to examine differences between intervention participants and controls. The study period spanned from 2020 to 2022. RESULTS: Intervention participants (n = 317,613, age 70.1 years, female sex 57.0%) had lower baseline optimal adherence than controls (n = 943,389, age 73.3, female sex 56.1%) for diabetes (76.9% vs 79.8%), hypertension (79.0% vs 83.0%), and cholesterol (78.6% vs 82.1%). The DID results showed that between 2020 and 2022, optimal adherence had significant absolute increases for intervention participants (diabetes: +4.0%, hypertension: +6.3%, cholesterol: +6.1%) vs controls who declined in adherence (diabetes: -1.6%, hypertension: -0.4%, cholesterol: -1.4%). All DID models were significant at P < 0.0001. Total cost of care was projected based on improvements in adherence. Based on PDC improvements for the test population, we estimate that the pharmacist consultations were associated with annual total health care cost savings of $10,329,284 ($109 per capita), $31,640,660 ($122 per capita), and $21,589,875 ($75 per capita) for test population patients with diabetes, hypertension, and hyperlipidemia, respectively. CONCLUSIONS: The study found that the pharmacist-led interventions were significantly associated with increased optimal adherence over 2 years. These findings demonstrate the potential of pharmacist-led interventions to improve medication adherence among older adults with chronic conditions. Strategies to expand pharmacist-provided care must be further examined.