Association of body fat-distribution markers with ischemic ECG changes and with 20-year all-cause and cardiovascular mortality in community-dwelling older adults

Background The association of body fat distribution markers with cardiovascular (CV) outcomes is not established among older adults. Methods 939 adults from the Glucose Intolerance, Obesity, and Hypertension study, were followed for a mean follow-up of 13 years (IQR 8). Nine fat-distribution markers were evaluated for their association with ischemic changes on ECG, and mortality. Multivariable regression models were used, and their performance was assessed using receiver operating characteristic (ROC) curves and net reclassification improvement (NRI) analysis. Results Mean baseline age was 72.3 ± 7 years and 471 (49%) were females. Upper quintiles (Q4–5) of weight-adjusted waist index (WWI) were associated with 1.8 (95%CI: 1.1–2.9, P = .01) greater odds for ischemic ECG changes. During follow-up, 466 (48.4%) participants died, 179 (38.4%) from CV causes. The WWI was the strongest predictor of both all-cause (HR = 1.4, 95%CI: 1.1–1.7, P = .002) and CV mortality (HR = 1.7, 95%CI: 1.2–2.3, P = .0031). ROC analysis showed better predictive ability for WWI (AUC = 0.442, 95%CI: 0.4–0.5, P = .003), and NRI analysis revealed that WWI outperformed other markers, correctly reclassifying 36% (95%CI: 0. 2–0.5, P = .01) and 32% (95%CI: 0.1–0.5, P < .001) of participants for all-cause and CV mortality respectively, compared with Body mass index (BMI)-based model. Conclusions WWI showed the strongest association with mortality and should be considered the preferred marker for identifying abnormal fat distribution, potentially replacing BMI. Key messages What is already known on this topic: Body mass index (BMI) correlates poorly with visceral fat yet data on which body fat distribution markers is the strongest predictor of cardiovascular (CV) morbidity and mortality is lacking among older adults. What this study adds: Weight adjusted waist index (WWI) was the strongest predictor of ischemic ECG changes, all-cause and CV mortality, outperforming BMI. How this study might affect research, practice or policy: WWI should be considered the preferred marker for identifying abnormal fat distribution, screening individuals at risk and guide medical intervention for weight reduction, potentially replacing BMI.