Context: Previous studies suggest that total testosterone levels influences lipid metabolism. It has not been investigated whether these levels are prospectively associated with an unfavourable lipid profile including increased risk of incident dyslipidemia.
Design and setting: We used data of 1468 men aged 2079 years, repeatedly examined in the population-based Study of Health in Pomerania. Serum total testosterone levels, measured by chemiluminescent enzyme immunoassays, were categorized into age-specific quartiles. We used generalized estimating Default (GEE) models to assess the prospective association of total testosterone with lipid profile including total cholesterol (TC), low-density lipoprotein cholesterol (LDL), high-density lipoprotein cholesterol (HDL), and triglyceride (TG) levels, as well as incident dyslipidemia at five years follow-up.
Results: Multivariable models revealed that total testosterone levels in the lowest quartile were associated with higher TC and TG levels in both, cross-sectional (TC: +0.23 mmol/l (95% CI, 0.020.42); TG: +0.73 mmol/l (95% CI, 0.530.94)) and longitudinal analyses (TC: +0.20 mmol/l (95% CI, 0.030.27); TG: +0.62 mmol/l (95% CI, 0.430.80)), but not with HDL or LDL levels. Dyslipidemia was a frequent condition (baseline prevalence: 57.1%) with a crude incidence rate of 46.6 per 1000 person-years. Total testosterone levels in the lowest quartile predicted dyslipidemia (age-adjusted odds ratios (OR) as compared with quartile 4 (highest) were 1.81 (95% CI, 1.132.89), 1.24 (95% CI, 0.821.89), 1.12 (95% CI, 0.721.72), and 1.00, respectively), particularly among men aged 2039 years (OR, 2.82; 95% CI, 1.286.20).
Conclusions: Low total testosterone levels are prospectively associated with an unfavorable lipid profile and increased risk of incident dyslipidemia. This finding is of particular interest as it could contribute to an explanation for the higher CVD risk in men with lower total testosterone levels.