Sex-specific Associations of Aldosterone and Renin With Body Composition: A Population-based Cohort Study

Abstract Context Renin–angiotensin–aldosterone system (RAAS) activation is closely linked to obesity; however, the sex-specific associations between RAAS activity and body composition among individuals without obesity are not well understood. Objective To investigate the associations of aldosterone and renin with body composition according to sex in the general population. Design Population-based cohort study. Setting Québec (Canada). Participants Adults aged 40 to 69 years enrolled in CARTaGENE between 2009 and 2010 (N = 3687). Exposures Plasma aldosterone and renin concentrations. Main Outcome Measures Body composition assessed via anthropometrics (waist circumference and waist-to-hip ratio), bioelectrical impedance (lean body mass, fat mass, and muscle mass), and cardiac magnetic resonance imaging (epicardial and pericardial adipose tissue volumes). Results The mean (SD) age and body mass index were 55 (8) years and 27.3 (4.8) kg/m2, respectively. Among males, higher aldosterone and renin were associated with increased waist circumference, increased waist-to-hip ratio, increased fat mass, decreased lean body mass, and decreased muscle mass (P < .05). Aldosterone (P = .02), but not renin (P = .43), was associated with increased ectopic cardiac adiposity in males. In contrast, higher renin (P < .05), but not aldosterone (P ≥ .05), was associated with increased waist circumference, increased waist-to-hip ratio, and increased cardiac adiposity in females. Among females, higher renin and aldosterone were associated with increased fat mass (P < .05) but were not associated with lean body mass or muscle mass (P ≥ .05). All aforementioned associations were independent of body weight. Conclusion Independent of body weight, increased RAAS activity is associated with unfavorable differences in body composition; however, the strength and pattern of association varies by sex.