Effect of 12 months of testosterone replacement therapy on metabolic syndrome components in hypogonadal men: data from the Testim Registry in the US (TRiUS)
- Equal contributors
1 University of Kansas Medical Center, 3901 Rainbow Blvd, MS2024, Kansas City, KS 66160, USA
2 Scott Department of Urology, Baylor College of Medicine, 6620 Main Street, Suite 1325, Houston, TX 77030, USA
3 Circle Medical LLC, 153 East Avenue, Suite 32, Norwalk, CT 06851, USA
4 Auxilium Pharmaceuticals, 40 Valley Stream Parkway, Malvern, PA 19355, USA
5 Miriam Hospital Men's Health Center, 164 Summit Avenue, Providence, RI 02906, USA
BMC Endocrine Disorders 2011, 11:18 doi:10.1186/1472-6823-11-18Published: 1 November 2011
Recent evidence suggests that there may be a bidirectional, physiological link between hypogonadism and metabolic syndrome (MetS), and testosterone replacement therapy (TRT) has been shown to improve some symptoms of MetS in small patient populations. We examined the effect of 12 months of TRT on MetS components in a large cohort of hypogonadal men.
Data were obtained from TRiUS (Testim® Registry in the United States), a 12-month, multicenter, prospective observational registry (N = 849) of hypogonadal men prescribed Testim 1% testosterone gel (5-10 g/day). Data analyzed included age, total testosterone (TT), free testosterone (FT), sex hormone-binding globulin (SHBG), and MetS components: waist circumference, blood pressure, fasting blood glucose, plasma triglycerides, and HDL cholesterol.
Of evaluable patients (581/849) at baseline, 37% were MetS+ (n = 213) and 63% were MetS- (n = 368). MetS+ patients had significantly lower TT (p < 0.0001) and SHBG (p = 0.01) levels. Patients with the lowest quartile TT levels (<206 ng/dL [<7.1 nmol/L]) had a significantly increased risk of MetS+ classification vs those with highest quartile TT levels (≥331 ng/dL [≥11.5 nmol/L]) (odds ratio 2.66; 95% CI, 1.60 to 4.43). After 12 months of TRT, TT levels significantly increased in all patients (p < 0.005). Despite having similar TT levels after TRT, only MetS+ patients demonstrated significant decreases in waist circumference, fasting blood glucose levels, and blood pressure; lowest TT quartile patients demonstrated significant decreases in waist circumference and fasting blood glucose. Neither HDL cholesterol nor triglyceride levels changed significantly in either patient population.
Hypogonadal MetS+ patients were more likely than their MetS- counterparts to have lower baseline TT levels and present with more comorbid conditions. MetS+ patients and those in the lowest TT quartile showed improvement in some metabolic syndrome components after 12 months of TRT. While it is currently unclear if further cardiometabolic benefit can be seen with longer TRT use in this population, testing for low testosterone may be warranted in MetS+ men with hypogonadal symptoms.