Metformin, testosterone, or both in men with obesity and low testosterone: A double-blind, parallel-group, randomized controlled trial.

BACKGROUND: Men with obesity tend to be insulin resistant and often have low-normal testosterone concentrations. We conducted a clinical trial aimed to evaluate potential therapeutic strategies for low testosterone in men with obesity. METHODS: We did a 1-year, parallel, randomized, double-blind, placebo-controlled trial, where we evaluated the independent and combined effects of metformin and testosterone in 106 men with obesity, aged 18-50 years, who had low levels of testosterone and no diabetes mellitus. The primary outcome was change in insulin resistance, measured as Homeostasis Model Assessment for Insulin Resistance (HOMA-IR) index. Secondary outcomes included changes in total and free serum testosterone, body composition, metabolic variables, erectile function, and health-related quality of life (HRQoL). RESULTS: In the intention-to-treat analysis, the HOMA-IR index decreased significantly in all active groups compared to placebo (metformin -2.4, 95 % CI -4.1 to -0.8, p = 0.004; testosterone -2.7, 95 % CI -4.3 to -1.1, p = 0.001; combination -3.4, 95 % CI -5.0 to -1.8, p < 0.001). Combination therapy was not superior to testosterone alone in decreasing insulin resistance (-0.7, 95 % CI -2.3 to 0.9, p = 0.383). Only the combination of metformin plus testosterone significantly increased total and free testosterone concentrations, compared to placebo. No significant changes in body composition (except for a higher decrease in fat mass in the metformin and combination group), metabolic variables, erectile function, or HRQoL were found with any treatment. CONCLUSIONS: Among men with obesity and low testosterone concentrations, the combination of metformin plus testosterone, metformin only, and testosterone only, compared to placebo, reduced insulin resistance with no evidence of additive benefit.

Adiposity is Associated with Decreased Serum 17-Hydroxyprogesterone Levels in Non-Diabetic Obese Men Aged 18-49: A Cross-Sectional Study.

Obesity is associated with decreased circulating testosterone levels, the main male sex hormone. However, there are a number of different male sex hormones whose dynamics remain poorly understood regarding this pathology. In this regard, 17 hydroxyprogesterone (17-OH progesterone), as an important precursor of testosterone synthetized in testes and adrenal glands, could play an essential role in testosterone deficiency in male obesity. Moreover, similarly to testosterone, 17-OH progesterone could be closely associated with visceral fat distribution and metabolic dysfunction. Thus, the aim of this study was to assess serum 17-OH progesterone levels in non-diabetic obese young men and to evaluate their relationship with clinical, analytical, and anthropometric parameters. We conducted a cross-sectional study including 266 non-diabetic men with obesity (BMI ≥ 30 kg/m2) aged 18-49 years; 17-OH progesterone and total testosterone (TT) were determined by high-performance liquid chromatography mass spectrometry. 17-OH progesterone levels were significantly lower in tertile 3 of body fat percentage in comparison with tertile 1 (0.74 ng/mL vs. 0.94 ng/mL, p < 0.01; Bonferroni correction) and in comparison with tertile 2 (0.74 ng/mL vs. 0.89 ng/mL, p = 0.02; Bonferroni correction). 17-OH progesterone levels correlated negatively with weight, BMI, waist circumference, insulin, homeostatic model assessment of insulin resistance (HOMA-IR), and visceral fat, and positively with TT, free testosterone (FT), luteinizing hormone, and fat-free mass percentage. Multivariate linear-regression analysis showed that body fat percentage and HOMA-IR were inversely associated with 17-OH progesterone levels, while FT and ACTH were positively linked to circulating 17-OH progesterone levels. In conclusion, in a population of non-diabetic obese young men, 17-OH progesterone levels were inversely associated with adiposity. Body fat percentage and insulin resistance were negatively related to 17-OH progesterone levels, whereas FT and ACTH levels were positively associated with 17-OH progesterone levels.

Prevalence of and risk factors for erectile dysfunction in young nondiabetic obese men: results from a regional study.

Erectile dysfunction (ED), a condition closely related to cardiovascular morbidity and mortality, is frequently associated with obesity. In this study, we aimed to determine the prevalence of ED and evaluate the associated risk factors in a cohort of 254 young (18-49 years) nondiabetic obese (body mass index [BMI] ≥ 30 kg m-2) men from primary care. Erectile function (International Index of Erectile Function [IIEF-5] questionnaire), quality of life (Aging Males' Symptoms [AMS scale]), and body composition analysis (Tanita MC-180MA) were determined. Total testosterone was determined using high-performance liquid chromatography-mass spectrometry. Multivariate logistic regression analysis was used to study the factors associated with ED. ED prevalence was 42.1%. Subjects with ED presented higher BMI, waist circumference, number of components of the metabolic syndrome, AMS score, insulin resistance, and a more unfavorable body composition than those without ED. Multivariate logistic regression analysis showed that a pathological AMS score (odds ratio [OR]: 4.238, P < 0.001), degree of obesity (BMI ≥ 40 kg m-2, OR: 2.602, P = 0.005, compared with BMI 30-34.9 kg m-2), high-density lipoprotein (HDL)-cholesterol levels (OR: 0.956, P = 0.004), and age (OR: 1.047, P = 0.016) were factors independently associated with ED. In conclusion, we demonstrate that, in a primary care-based cohort of nondiabetic young obese men, ED affected >40% of subjects. A pathological AMS score, the degree of obesity, and age were positively associated with ED, while elevated HDL-cholesterol levels were inversely associated with the odds of presenting ED. Further prospective studies are needed to evaluate the long-term consequences of ED in this population.

Cross-Sectional, Primary Care-Based Study of the Prevalence of Hypoandrogenemia in Nondiabetic Young Men with Obesity.

OBJECTIVE: Obesity-associated hypoandrogenemia is increasing in parallel to the obesity epidemic. The prevalence of hypoandrogenemia in nondiabetic young men with obesity is not known. This study aimed to evaluate the prevalence of hypoandrogenemia and associated risk factors in this population. METHODS: This cross-sectional study included 266 nondiabetic men < 50 years of age with obesity who were referred from primary care. Total testosterone (high-performance liquid chromatography mass spectrometry), sex hormone-binding globulin, free testosterone (FT), luteinizing hormone (LH), high-sensitivity C-reactive protein, and homeostatic model assessment of insulin resistance were determined. Body composition and erectile function were also assessed. Hypoandrogenemia was defined as FT level < 70 pg/mL. RESULTS: Subnormal FT concentrations were found in 25.6% of participants. Hypoandrogenemia prevalence was different along the BMI continuum, being > 75% in individuals with BMI ≥ 50 kg/m2 . A multivariate regression analysis indicated that increasing BMI (P < 0.001), age (P = 0.049), and reduced LH levels (P = 0.003) were independent risk factors for hypoandrogenemia. CONCLUSIONS: In a primary care-based cohort of nondiabetic young men with obesity, hypoandrogenemia was a very prevalent finding and was directly associated with adiposity. Obesity, age, and reduced LH levels were independent risk factors associated with hypoandrogenemia. Further prospective studies are needed to evaluate the long-term consequences of hypoandrogenemia in this population.