Waist measures improve cardiovascular risk classification

Waist circumference and waist-to-hip ratio added meaningful cardiovascular risk information beyond body mass index.
*Pooled prospective cohort study; Level 2 (OCEBM).

Citation

Dardari ZA, Yao Z, Zhang J, et al. Risk Reclassification Beyond BMI by Waist Circumference and Waist-to-Hip Ratio Across 9 Cardiovascular Outcomes. JACC. 2026;88:670-684.

Background

Body mass index is widely used to classify weight status, but it does not show where body fat is carried. Abdominal fat may better identify people at higher heart and blood vessel risk.

Patients

259,388 adults from 15 prospective cohorts without known coronary heart disease at baseline. Exclusions included body mass index below 18.5, missing body mass index, and prior disease-specific outcomes for those analyses.

Intervention

Risk classification using waist circumference or waist-to-hip ratio added to body mass index categories.

Control

Traditional body mass index categories alone, with normal weight and low waist measure as the reference group.

Outcome

Heart attack, stroke, heart failure, atrial fibrillation, coronary heart disease, cardiovascular disease, coronary death, cardiovascular death, and all-cause death.

Follow-up Period

Median 20.0 years.

Results

Finding Result
Normal weight but high abdominal fat 5% by waist circumference; 18% by waist-to-hip ratio
Overweight with high abdominal fat 39% by waist circumference; 40% by waist-to-hip ratio
Obesity but lower abdominal fat 9% by waist circumference; 45% by waist-to-hip ratio
Obesity: atrial fibrillation attributable to high waist circumference 48.9% (95% CI 41.2 to 55.6)
Obesity: heart failure attributable to high waist circumference 46.2% (95% CI 30.1 to 58.6)
Obesity: coronary death attributable to high waist circumference 36.3% (95% CI 28.5 to 43.3)

Among normal-weight or overweight adults, high waist measures were associated with 15% to 50% greater risk for most outcomes. This was an observational analysis, so number needed to treat does not apply.

Limitations

Observational design cannot prove causation. Residual confounding is possible. Waist measures were assessed once. Physical activity, diet, and genetic obesity risk were unavailable. Historical cohorts may understate current obesity-related risk.

Funding

Mostly public/government grants; one author reported several industry advisory roles.

Clinical Application

Measure waist circumference, not body mass index alone, when assessing cardiovascular risk in primary prevention.