Visceral adiposity index (VAI), a powerful predictor of incident hypertension in prehypertensives

Abstract

Prehypertension (defined by The Seventh Report of the Joint National Committee on the Prevention, Detection, Evaluation, and Treatment of High Blood Pressure, JNC-7) is relevant to a higher cardiovascular risk than normotensives. Early intervention in this particular population is essential to avoid progression into hypertension (HTN). This study is to explore whether visceral adiposity index (VAI) can strongly predict the incidence of HTN in community-based prehypertensives. A prospective observational cohort study was conducted from September 2011 to June 2012 in urban communities of Chengdu, Sichuan Province, China. 780 subjects (male 320, female 460) were evaluated on anthropometrical indices, blood pressure, blood samples, brachial-ankle pulse wave velocity, of whom 360 prehypertensives (male 160, female 200) were recruited for a 5-year follow-up. Overall, 97 subjects (male 37, female 60) developed HTN. The risk for developing HTN in the future increases with increasing VAI levels. The OR of the upper quartile is 3.719 (95% CI 1.481-9.338, P = 0.005) after adjusting for confounders. The ROC results reveal that VAI is not considered superior to other indices on account of the significant overlapping confidence intervals. The area under the curves (AUC) of Model 5 (combination of VAI and WC) is significantly higher than BMI, WC and WHR (P < 0.05). The AUC of Model 4 (combination of VAI and BMI) is found to be significantly higher than BMI and WHR (P < 0.05), and is also higher than WC in all subject groups and in the male subgroup, but not in the female subgroup. VAI at baseline is an independent risk factor and early predictor of incident HTN in prehypertensives. The predictive value is not stronger than other traditional obesity indices (BMI, WC and WHR); however, it is superior to the latter by combining VAI and WC. Namely, VAI may help identify individuals at high risk of evolving into HTN in this particular population.

Keywords: BaPWV; Prehypertension; Visceral adiposity index.