The association of serum testosterone with dyslipidemia is mediated by obesity: the Henan Rural Cohort Study

This study aimed to evaluate the relationships of serum testosterone with dyslipidemia and blood lipid levels and test whether obesity mediated these associations by gender in Chinese rural population.

A total of 6150 subjects were finally analyzed in this study. Serum testosterone for each subject was detected by liquid chromatography equipped with tandem mass spectrometry. Logistic regression and linear regression were employed to evaluate the associations of serum testosterone with the prevalence of dyslipidemia and blood lipid levels. Mediation analysis was conducted to identify the mediation effects of obesity on the relationship between serum testosterone and dyslipidemia. After adjusting for multiple confounders, per unit change in serum ln-testosterone levels was associated with a decreased prevalent dyslipidemia in men (odds ratio (OR): 0.785, 95% confidence interval (CI) (0.708, 0.871)). Males with the levels of serum testosterone in the third or fourth quartiles had a 49.4% (OR: 0.506, 95% CI 0.398, 0.644) or 67.1% (OR: 0.329, 95% CI 0.253, 0.428) significantly lower odds of prevalence of dyslipidemia. In addition, a onefold increase in ln-testosterone was related to a 0.043 mmol/L (95% CI 0.028, 0.059) increase in high-density lipoprotein cholesterol (HDL-C) in men. Results of the mediation analysis suggested that obesity played a partial role in the association of testosterone with dyslipidemia in men.

These findings suggested that serum testosterone levels were negatively associated with lipid levels and prevalent dyslipidemia, and obesity mediated the effects of serum testosterone on dyslipidemia in men, implying that obesity prevention should be highlighted to decrease the prevalence of dyslipidemia related to changes in testosterone levels.