Exploring cut-off values for large waist circumference in older adults: a new methodological approach

BACKGROUND: There is an ongoing debate about the applicability of current criteria for large waist circumference (WC) in older adults. OBJECTIVES: Our aim was to explore cut-off values for large WC in adults aged 70 years and older, using previously used and new methods. DESIGN: Prospective cohort study. PARTICIPANTS: Data of 1049 participants of the Longitudinal Aging Study Amsterdam (LASA) (1995-1996), aged 70-88y, were used. MEASUREMENTS: Measured BMI and WC, and self-reported mobility limitations. RESULTS: Linear regression analyses showed that the values of WC corresponding to BMI of 25kg/m2 and 30kg/m2 were higher than the current cut-offs. Cut-offs found in men were 97 and 110cm, whereas 88 and 98cm represented the cut-offs in women. Areas under the Receiver Operating Characteristic (ROC) curves showed that the accuracy to predict mobility limitations improved when the higher cut-offs were applied. Spline regression curves showed that the relationship of WC with mobility limitations was U-shaped in men, while in women, the risk for mobility limitations increased gradually with increasing WC. However, at the level of current cut-off values for WC the odds for mobility limitations were not increased. CONCLUSION: Based on results of extensive analyses, this study suggests that the cut-offs for large WC should be higher when applied to older adults. The association of WC with other negative health outcomes needs to be investigated to establish the final cut-points