The Influence of Abdominal Obesity on Endothelial Function of the Tibial Artery in the Elderly Essential Hypertensives of Different Sex

Abstract

Abstract Background To investigate the relationship between abdominal obesity and endothelial function of the tibial artery in the elderly essential hypertensives of different sex. Methods A total of 658 elderly patients (≥60 years old) with essential hypertension and 64 elderly subjects without clinical evidence of hypertension were recruited from the department of geriatrics from August 2000 to May 2016. The dilatation of anterior tibial artery induced by reactive hyperemia was examined by high-resolution vascular ultrasound and was defined as endothelium-dependent dilatation (EDD). All the participants were divided into 4 groups based on blood pressure (≥140/90 mm Hg) and waist circumference (male ≥90 cm, female ≥85 cm): normotensive without abdominal obesity (n = 34), normotensive with abdominal obesity (n = 30), hypertensive without abdominal obesity (n = 287), and hypertensive with abdominal obesity (n = 371). Results A gradual decline in EDD was observed from normotensive without abdominal obesity (9.37 ± 1.11%), normotensive with abdominal obesity (8.59 ± 0.99%), hypertensive without abdominal obesity (7.70 ± 0.30%) to hypertensive with abdominal obesity (6.75 ± 0.26%) (P < 0.05). There was no significant difference in EDD between the male and female elderly hypertensives with or without abdominal obesity. In male elderly hypertensives, EDD in those with central obesity was more blunted compared with those without central obesity (6.31 ± 0.38% vs. 7.46 ± 0.38%, P < 0.05). Whereas, in female elderly hypertensives, EDD in those with abdominal obesity was similar to those without abdominal obesity. In male elderly hypertensives, EDD was correlated with waist circumference (r = −0.194, P < 0.05) while such association was not shown in females. Multivariate linear regression analysis revealed that waist circumference was associated with EDD (β = −0.161, P < 0.05) in the male elderly hypertensives, but not in females. Conclusions Waist circumference is an influencing factor of EDD in male elderly essential hypertension patients. However, abdominal obesity has little effect on EDD of the tibial artery in female elderly hypertensives.