Medicare Star Ratings Reveal Strong Link Between Medication Adherence and Cardiovascular Outcomes

A recent peer-reviewed study analyzed the relationship between Medicare Star Ratings for medication adherence and other intermediate and process health measures related to cardiovascular diseases and diabetes. The cross-sectional analysis covered health plan performance data from 2015 to 2025. It assessed how adherence to specific medication classes like renin-angiotensin system antagonists (RASA), noninsulin antidiabetics, and statins correlated with clinical outcomes such as blood pressure control, blood glucose control, and statin therapy use among patients with cardiovascular diseases and diabetes. The findings demonstrated that health plans with top ratings (5 stars) for medication adherence had significantly higher odds of achieving high ratings in related clinical process measures. For instance, plans scoring 5 stars in antidiabetic adherence were more likely to achieve high scores in blood glucose control, evidencing a strong link between adherence and clinical outcomes. The research suggests that targeted interventions to improve medication adherence can enhance both clinical outcomes for patients and financial incentives for health plans. This insight is crucial for payers and providers aiming to optimize performance within Medicare Star Ratings frameworks, emphasizing the role of medication adherence in broader quality and compliance metrics. The study was conducted by Dickinson and Company and published in The American Journal of Managed Care in 2025.