A study in JAMA Network Open, supported by the National Heart, Lung, and Blood Institute, finds a clinical calculation for developing atherosclerotic heart disease, the narrowing of the arteries caused by plaque that can lead to a heart attack, stroke, or death, works well for most people but may overestimate 10-year risks for people with moderate to severe obesity.
The pooled cohort equation (PCE) integrates age, sex, race, cholesterol, blood pressure, medication use, diabetes, and smoking history into a 10-year prediction for coronary heart disease-related events, such as a heart attack or stroke. The risks range from low, less than a 5% chance, to intermediate, starting at 7.5%, and high, classified as 20% or more. The study found people with a predicted coronary heart disease risk of 20% or more, regardless of their body weight, had fewer cardiac incidents than predicted 10 years before. Similarly, obese men and obese black study participants had higher heart disease risks, based on this model, compared to actual heart-related events. Early placement in a high-risk heart disease category may result in unnecessary medical interventions, such as premature use of cholesterol-lowering drugs.
To reach these conclusions, the researchers used eight studies to compare prior 10-year heart disease risk estimates with the actual outcomes of 37,311 adults, ages 40 to 79. Despite the outliers, the researchers find the heart disease prediction tool is still useful for most patients, including those with obesity. For example, the average risk estimate for patients developing coronary heart disease was 10.3 to 11.6%. The actual average was 8.6 to 10.7%. The assessments were most accurate for people on the threshold of intermediate heart disease risk, 7.5%.