Association between serum levels of testosterone and biomarkers of subclinical atherosclerosis

Objective: To investigate the association between serum levels of testosterone and biomarkers of subclinical atherosclerosis based on data from 119 middle-aged men of the general population.Methods: Testosterone, Apolipoprotein A-1 (ApoA-1), Apolipoprotein B (ApoB), Apolipoprotein B-to-Apolipoprotein A-1 ratio (ApoB-to-ApoA-1), high-sensitive C-reactive protein (hsCRP), and fibrinogen levels were measured. Data were also gathered based on age, BMI, waist circumference, smoking, alcohol consumption, and family history of cardiovascular diseases. Men were classified into two groups based on testosterone levels: hypogonadal (testosterone 12nmol/L) and eugonadal men (testosterone >12nmol/L).Results: When compared to eugonadal, the hypogonadal men were significantly older (56years vs. 55years, p=.03), had greater BMI (28kg/cm(2) vs. 26kg/cm(2), p=.01), and higher waist circumference (104cm vs. 100cm, p=.01). Moreover, ApoB, ApoB-to-ApoA-1 ratio, and hsCRP were significantly higher in hypogonadal men compared to eugonadal men (1.1g/L vs. 1.0g/L, p=.03), (0.8 vs. 0.7, p=.03), (3.3mg/L vs. 2.0mg/L, p=.01), respectively. On the other hand, ApoA-1 and fibrinogen levels did not differ significantly between groups (p>.05). In an adjusted multivariate regression analysis model, only ApoB showed a significant negative association with testosterone levels (=-0.01; 95% CI=-0.02, -1.50; p=.04).Conclusion: Testosterone levels showed an inverse relation to ApoB, a biomarker implicated in subclinical atherosclerosis. These findings support the hypothesis that low testosterone levels play a role in atherosclerosis.