BMI and Waist Circumference Jointly Predict Mortality Risk in Older Adults

In US adults aged ≥65 years, overweight and class I–II obesity were associated with lower all-cause mortality risk, whereas high waist circumference and being underweight were associated with higher mortality risk, highlighting the importance of central adiposity and the limitations of BMI alone for mortality risk stratification. Using 14 years of longitudinal data (2011–2024) from 6,905 participants in the National Health and Aging Trends Study, researchers assessed the independent and joint associations of BMI category and waist circumference (WC) with all-cause mortality after adjustment for age, race, education, annual income, smoking status, and homebound status. Compared with normal-weight males, overweight males had a lower mortality risk (HR, 0.54), as did males with class I and II obesity (HR, 0.49), while high WC was associated with greater mortality risk (HR, 1.24); similar patterns were observed in females. In joint BMI-WC analyses, overweight was associated with lower mortality risk regardless of WC, while class I and II obesity with high WC was also associated with lower mortality risk among males. In contrast, being underweight regardless of WC and having normal weight with high WC were associated with higher mortality risk in both sexes. These findings underscore the adverse association of central adiposity with mortality and the limitations of BMI-only classification in older adults. Source: https://agsjournals.onlinelibrary.wiley.com/