Modifiable Risk Among Medicare Beneficiaries Enrolled in the Million Hearts® Cardiovascular Disease Risk Reduction Model
Authors: Markovitz A. 
Published: August 2020

Research ObjectiveThe Million Hearts ® Cardiovascular Disease (CVD) Risk Reduction Model aims to reduce CVD for those at highest 10‐year risk of myocardial infarction or stroke, but it is unclear how much risk is modifiable through key prevention strategies—blood pressure control, cholesterol control, smoking cessation, and aspirin therapy.Study DesignUsing clinical data and Medicare Part D pharmacy claims, we examined CVD risk factors, medication use, and 10‐year risk of myocardial infarction or stroke at baseline among Medicare beneficiaries enrolled in the Million Hearts Model. Among beneficiaries who met the model’s criteria for high (>30%) or medium (15‐30%) CVD risk, we identified the proportion of risk that could be modified through risk factor control, using the Million Hearts® Longitudinal Atherosclerotic CVD Risk Assessment Tool to predict future risk after reaching target goals. Targets included reducing systolic blood pressure (SBP) below 130 mmHg, reducing low‐density lipoprotein below 70 mg/dL, universal smoking cessation, and aspirin use (where appropriate).Population Studied297,740 Medicare beneficiaries enrolled in the Million Hearts Model by intervention or control organizations.Principal FindingsIn both the intervention and control groups, eighteen percent of beneficiaries were at high risk for myocardial infarction or stroke and 40% were at medium risk. High SBP and other modifiable risk factors were common despite prevalent medication use at baseline, including antihypertensive use among 90% of high‐risk beneficiaries. We found that if beneficiaries reached targets, it would lead to a 15 percentage point absolute risk reduction in high‐risk beneficiaries, amounting to 39% of their CVD risk, and a six percentage point risk reduction in medium‐risk beneficiaries, amounting to 28% of their CVD risk. Among the prevention strategies, blood pressure control alone would result in the largest risk reduction for high‐risk beneficiaries, leading to an 11 percentage point risk reduction. Blood pressure and cholesterol control would each result in a two percentage point risk reduction for medium‐risk beneficiaries.ConclusionsThere is substantial room to reduce CVD risk among the Million Hearts Model’s target Medicare population. Blood pressure control has the greatest opportunity to reduce risk among the high‐risk group, and the greatest benefits may come from medication intensification, rather than initiation, as most beneficiaries are already on medication.Implications for Policy or PracticeWithout a substantial amount of modifiable risk, the Million Hearts Model could not achieve its intended goal of reducing the risk of heart attacks and stroke. These findings are encouraging that almost 40 percent of all CVD risk in the high‐risk target population could be reduced through the key Million Hearts prevention strategies. Blood pressure control, in particular, has a large potential to reduce CVD risk in the Million Hearts target population and likely more generally for higher risk Medicare beneficiaries across the United States.Primary Funding SourceCenters for Medicare and Medicaid Services.