Relationship between Serum Total Testosterone Concentration and Metabolic Syndrome in Premenopausal Obese Women

Background: Men with low testosterone levels are at an increased risk of developing metabolic syndrome, irrespective of age or obesity. However, the relationship between metabolic syndrome and testosterone levels in women remains unclear. We compared the total testosterone concentrations between premenopausal obese women with and without metabolic syndrome and identified the factors affecting these concentrations. Methods: A single-center retrospective analysis was conducted using the medical records of 580 premenopausal women with obesity. The diagnostic criteria for metabolic syndrome were established using the National Cholesterol Education Program Adult Treatment Panel III guidelines. Results: The mean +/- standard deviation age, weight, and body mass index were 38.8 +/- 8.4 years, 78.0 +/- 11.8 kg, and 30.0 +/- 4.1 kg/m(2), respectively. The mean total testosterone concentration was lower in the metabolic syndrome group than in the non-metabolic syndrome group (n=385 vs. n=195; 0.22 +/- 0.10 ng/mL vs. 0.24 +/- 0.11 ng/mL; P<0.001). In a model adjusted for age, body mass index, skeletal muscle mass, body fat mass, and body fat percentage, the odds ratio for metabolic syndrome with respect to the total testosterone level was 0.128 (P=0.028). Testosterone concentration was negatively correlated with age (r=-0.334), systolic blood pressure (r=-0.084), and triglyceride concentration (r=-0.093) but positively correlated with weight (r=0.144), body mass index (r=0.140), waist circumference (r=0.133), body fat mass (r=0.167), and body fat percentage (r=0.167). Stepwise regression analysis revealed that age (beta=-0.004, P<0.001), body mass index (beta=0.003, P=0.004), and high-density lipoprotein cholesterol concentration (beta=0.001, P=0.019) were independently associated with total testosterone concentration (adjusted R-2=12.6%). Conclusion: Metabolic syndrome and obesity may be independently associated with testosterone levels in premenopausal women with obesity.