Long-Term Testosterone Therapy Improves Liver Parameters And Steatosis In Hypogonadal Men: A Prospective Controlled Registry Study

Non-alcoholic fatty liver disease (NAFLD) is associated with cardiovascular disease (CVD) and both are prevalent in men with testosterone deficiency. Long-term effects of testosterone therapy (TTh) on NAFLD are not well studied. This observational, prospective, cumulative registry study assesses long-term effects of testosterone undecanoate (TU) on hepatic physiology and function in 505 hypogonadal men (T levels <= 350 ng/dL). Three hundred and twenty one men received TU 1000 mg/12 weeks for up to 12 years following an initial 6-week interval (T-group), while 184 who opted against TTh served as controls (C-group). T-group patients exhibited decreased fatty liver index (FLI, calculated according to Mayo Clinic guidelines) (83.6 +/- 12.08 to 66.91 +/- 19.38), gamma-GT (39.31 +/- 11.62 to 28.95 +/- 7.57 U/L), bilirubin (1.64 +/- 4.13 to 1.21 +/- 1.89 mg/dL) and triglycerides (252.35 +/- 90.99 to 213 +/- 65.91 mg/dL) over 12 years. Waist circumference and body mass index were also reduced in the T-group (107.17 +/- 9.64 to 100.34 +/- 9.03 cm and 31.51 +/- 4.32 to 29.03 +/- 3.77 kg/m(2)). There were 25 deaths (7.8%) in the T-group of which 11 (44%) were cardiovascular related. In contrast, 28 patients (15.2%) died in C-group, and all deaths (100%) were attributed to CVD. These data suggest that long-term TTh improves hepatic steatosis and liver function in hypogonadal men. Improvements in liver function may have contributed to reduced CVD-related mortality.