Complex Association of Sex Hormones on Left Ventricular Systolic Function: Insight into Sexual Dimorphism

Abstract

Normal values of left ventricular ejection fraction (LVEF) and absolute values of global longitudinal strain (GLS) are lower in men than in women. Data concerning the association of sex hormone levels on these left ventricular systolic function surrogates are scarce. The aim of this study was to determine the association of sex hormones with systolic left ventricular function in healthy subjects and patients with congenital adrenal hyperplasia (CAH) as a model of testosterone dysregulation. Eighty-four adult patients with CAH (58 women; median age, 27years; interquartile range, 23-36years) and 84 healthy subjects matched for sex and age were prospectively included. Circulating concentrations of sex hormones were measured within 48hours of echocardiography with assessment of LVEF and left ventricular longitudinal, radial, and circumferential strain. LVEF and GLS were higher in healthy women than in healthy men (63.9±4.2% vs 60.9±5.1% [P<.05] and 20.0±1.9% vs 17.9±2.4% [P<.001], respectively), while there was no difference in LVEF or GLS between women and men with CAH (63.9±4.5% vs 63.0±4.6% [P= NS] and 19.4±2.2% vs 18.3±1.8% [P= NS], respectively). Bioavailable testosterone levels were higher in women with CAH than in female control subjects (0.08ng/mL [interquartile range, 0.04-0.14ng/mL] vs 0.16ng/mL [interquartile range, 0.04-0.3ng/mL], P<.001) and lower in men with CAH than in male control subjects (2.3ng/mL [interquartile range, 1.3-3ng/mL] vs 2.9ng/mL [interquartile range, 2.5-3.4ng/mL], P<.05). In men, LVEF and GLS were negatively correlated with bioavailable testosterone levels (r=-0.3, P≤.05, and r=-0.45, P<.01, respectively), while midventricular radial strain was positively correlated with bioavailable testosterone level (r=0.38, P<.05). The absolute value of circumferential strain was positively correlated with follicle-stimulating hormone (r=0.65, P<.0001). These data support that the existence of sex dimorphism concerning left ventricular systolic cardiac function is significantly associated with testosterone levels.