Optimal Cutoff Values for High-Risk Waist Circumference in Older Adults Based on Related Health Outcomes

The authors aimed to explore optimal cutoffs for high-risk waist circumference (WC) in older adults to assess the health risks of obesity. Prospective data from 4,996 measurements in 2,232 participants aged >= 70 years were collected during 5 triennial measurement cycles (1992/1993-2005/2006) of a population-based cohort study, the Longitudinal Aging Study Amsterdam (Amsterdam, the Netherlands). Cross-sectional associations of WC with pain, mobility limitations, incontinence, knee osteoarthritis, cardiovascular disease, and diabetes were studied. Generalized estimating equations models were fitted with restricted cubic spline functions in order to carefully study the shapes of the associations. Model fits for applying different cutoffs to categorize WC in the association with all outcomes were tested using the quasi-likelihood under the Independence Criterion (QIC). On the basis of the spline regression curves, potential WC cutoffs of approximately 109 cm in men and 98 cm in women were proposed. Based on the model fit, cutoffs between 100 cm and 106 cm were equally applicable in men but should not be higher. In women, the QIC confirmed an optimal cutoff of 99 cm.