Association between waist circumference (WC) values and hypertension, heart disease (HD) and diabetes, reported by the elderly--SABE Survey: Health, Wellness and Aging, 2000 and 2006.

The positive association between WC and systemic arterial hypertension (SAH), diabetes mellitus (DM) and HD calls for investigation in the elderly. The objective of the present study was to identify WC values, so as better to determine the risk of these diseases. This was a longitudinal study using the data of 405 elderly participants of the SABE Survey: Health, Well-being and Aging, undertaken in São Paulo, in 2000 and 2006. The study variables were WC, sex, age group, ethnicity, and body mass index (BMI) (2000) and SAH, DM and HD (2006). The area under the Receiver Operating Caracteristics (ROC) curve (AUC) and confidence intervals of 95% was used to estimate the performance of WC values in correctly discriminating among the elderly, according to the reference or not to diseases associated with WC. WC critical values were identified by the highest positive likelihood ratio (PLR), and negative likelihood ratio (NLR) equal to zero. The AUC showed the satisfactory performance of WC critical values in discriminating between reports of DM in individuals of 60-74 years of age. The WC critical values identified were ≥87 cm for women and ≥99 cm for men, which presented a better performance in relation to the AUC value than to the WC values commonly used. The WC critical values identified in this study showed better discriminatory power of foretelling reference to DM than did the WC values commonly used.