Does endothelial dysfunction correlate better with waist-to-hip ratio than with body mass index or waist circumference among obese patients?
OBJECTIVE
Obesity is associated with cardiovascular disease, affecting large arteries and the microcirculation. Waist circumference and body mass index are routinely employed as measures for assessing obesity-related health risk, whereas waist-to-hip ratio is not. We aimed to investigate the association between brachial vascular reactivity and body mass index, waist circumference, and waist-to-hip ratio.


METHODS
Eighty-five volunteers (21 men/66 women), aged between 20 and 55 years, underwent determination of waist circumference, body mass index, waist-to-hip ratio, and endothelial function by venous occlusion plethysmography. Forearm blood flow was measured in response to intrabrachial artery infusions of 3 different concentrations of endothelium-dependent (acetylcholine 7.5, 15, and 30 mg/min) and endothelium-independent (sodium nitroprusside 2, 4, and 8 mg/min) vasodilators.


RESULTS
There was an inverse correlation of body mass index and waist circumference with forearm blood flow increments after acetylcholine and sodium nitroprusside infusions, while waist-to-hip ratio showed an inverse correlation with forearm blood flow increments only after acetylcholine. When subjects older than 40 years (n = 25) were excluded from the analysis, the inverse correlation of body mass index with forearm blood flow increments after acetylcholine infusion no longer existed, while waist circumference and waist-to-hip ratio showed the same results observed before.


CONCLUSIONS
The waist-to-hip ratio is probably a better estimator of endothelial dysfunction and possibly of cardiovascular risk than body mass index. These findings underscore the importance of routinely collecting hip circumference as an obesity index and risk estimator.
Laboratório de Pesquisas em Microcirculação, Universidade do Estado do Rio de Janeiro, RJ, Brazil.
Nivaldo Ribeiro
NR
Villela
Luiz Guilherme Kraemer
LG
Aguiar
Luciana
L
Bahia
Daniel
D
Bottino
Eliete
E
Bouskela
D000328:Adult; D001824:Body Constitution; D015992:Body Mass Index; D004730:Endothelium, Vascular / Q000503:physiopathology*; D005260:Female; D005542:Forearm / Q000098:blood supply; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000503:physiopathology*; D010991:Plethysmography; D012039:Regional Blood Flow / Q000502:physiology; D015203:Reproducibility of Results; D049629:Waist-Hip Ratio / Q000379:methods*