Sex influences the effect of body mass index on the vascular response to angiotensin II in humans

Abstract

Sex influences the cardiorenal risk associated with body mass index (BMI). The role of the renin-angiotensin-aldosterone system in adiposity-mediated cardiorenal risk profiles in healthy, non-obese men and women was investigated. Systemic and renal hemodynamic responses to angiotensin-II (AngII) as a function of BMI, waist and hip circumference, waist-hip ratio, as well as fat and lean mass were measured in 18 men and 25 women in high-salt balance, stratified by BMI (<25 kg/m2 (ideal body weight (IBW)) vs. ≥25 kg/m2 overweight)). In men (n = 7, BMI 23 ± 1 kg/m2) and women (n = 14, BMI 22 ± 2 kg/m2) of IBW, BMI was not associated with the systolic blood pressure (SBP) response to AngII. In contrast, overweight men (n = 11, 29 ± 2 kg/m2) demonstrated a progressively more blunted vasoconstrictor SBP response to AngII challenge as BMI increased (P = 0.007), even after adjustment for covariates. Women maintained the same relationship between BMI and the SBP response to AngII irrespective of weight status (P = 0.2, IBW vs. overweight women). Compared to BMI, other adiposity measures showed similar associations to systemic AngII responsiveness in men but not in women. Increasing BMI was associated with a blunted renovasoconstrictor response to AngII in all subjects, but was more pronounced in men. Sex influences the effect of adiposity on vascular angiotensin-responsiveness.