Objective To study the relationship between endogenous sex hormone levels and atherosclerosis of the carotid artery measured by ultrasonography.

Methods Analysis of the healthy elders from a population-based cohort study in 9 communities of Beijing. carotid intima-media thickness (IMT) and atherosclerotic plaques were determined ultrasonographically. Sex hormone levels were measured by immunoassay. The data were analysed with ANOVA and logistic regression analysis.

Results There was a inverse association between testosterone and plaque formation in females (p<0.001), whereas no association was found in males. Logistic regression analysis showed that females with a testosterone level in the lowest quintile (<0.49 nmol/l) were more likely (OR=3.11, p=0.002) to be in the plaque formation independently of age and the other risk factors. Age (OR=1.07 year-1), LDL (OR=1.65, p=0.027), physical exercise (OR=0.54, p=0.006), and IL-6 (OR=1.05, p=0.022) were also independently associated with plaque formation.

Conclusions Testosterone concentrations are negatively associated with carotid artery atherosclerosis in females, experimental and prospective studies are needed to determine the possible therapeutic role of testosterone in atherosclerosis.