Accuracy and measures of association of anthropometric indexes of obesity to identify the presence of hypertension in adults: a population-based study in Southern Brazil

Abstract

PURPOSE: This study proposes to examine the accuracy of four anthropometric indexes of obesity to identify the presence of hypertension and assess differences in the estimation and strength of effect measures of the association between each anthropometric measure and hypertension in Brazilian adults. METHODS: A population-based cross-sectional study was carried out with a sample of 1,720 adults from Florianópolis, Brazil. Receiver operating characteristic (ROC) curves were performed to identify the sensitivity and specificity of the best cutoff values for anthropometric indexes (body mass index—BMI, waist circumference—WC, waist-to height ratio—WHtR and conicity index—C-index) for prediction of hypertension. The associations between anthropometric indexes and hypertension were analyzed by Poisson regression expressed as Prevalence Ratios (95% CI) adjusted for socio-demographic variables, health behavior, height, and anthropometric indexes. RESULTS: Of the four anthropometric indexes studied, BMI, WC, and WHtR were found to have the largest areas under the ROC curve relative to hypertension in both sexes. The cutoff values in women and men associated with presence of hypertension were BMI of 24.9 and 24.6 kg/m², WC of 86.2 and 89.5 cm, WHtR of 0.49 and 0.50, and C-index of 1.15 and 1.18, respectively. WC and BMI had greater magnitude of association with presence of hypertension, adjusting for socio-demographic variables, health behavior, height, and anthropometric indexes in women and men, respectively. CONCLUSIONS: Anthropometric indexes provide an effective, simple, inexpensive, and non-invasive means for a first-level screening for hypertension.