Long-term testosterone therapy in hypogonadal men ameliorates elements of the metabolic syndrome: an observational, long-term registry study

AimThe goal of this study was to determine if long-term testosterone (T) therapy in men with hypogonadism, henceforth referred to as testosterone deficiency (TD), ameliorates or improves metabolic syndrome (MetS) components. MethodsWe performed a cumulative registry study of 255 men, aged between 33 and 69years (mean 58.026.30) with subnormal plasma total T levels (mean: 9.931.38; range: 5.89-12.13nmol/l) as well as at least mild symptoms of TD assessed by the Aging Males' symptoms scale. All men received treatment with parenteral T undecanoate 1000mg (Nebido((R)), Bayer Pharma, Berlin, Germany), administered at baseline and 6weeks and thereafter every 12weeks for up to 60months. Lipids, glucose, liver enzymes and haemoglobin A(1c) analyses were carried out in a commercial laboratory. Anthropometric measurements were also made throughout the study period. ResultsTestosterone therapy restored physiological T levels and resulted in reductions in total cholesterol (TC) [7.29 +/- 1.03 to 4.87 +/- 0.29mmol/l (281.58 +/- 39.8 to 188.12 +/- 11.31mg/dl)], low-density lipoprotein cholesterol [4.24 +/- 1.07 to 2.84 +/- 0.92mmol/l (163.79 +/- 41.44 to 109.84 +/- 35.41mg/dl)], triglycerides [3.14 +/- 0.58 to 2.16 +/- 0.13mmol/l (276.16 +/- 51.32 to 189.78 +/- 11.33mg/dl)] and increased high-density lipoprotein levels [1.45 +/- 0.46 to 1.52 +/- 0.45mmol/l (56.17 +/- 17.79 to 58.85 +/- 17.51mg/dl)] (p<0.0001 for all). There were marked reductions in systolic and diastolic blood pressure, blood glucose, haemoglobin A(1c), C-reactive protein (6.29 +/- 7.96 to 1.03 +/- 1.87U/l), alanine aminotransferase and aspartate aminotransferase (p<0.0001 for all). ConclusionsLong-term T therapy, at physiological levels, ameliorates MetS components. These findings strongly suggest that T therapy in hypogonadal men may prove useful in reducing the risk of cardiometabolic diseases.