0
selected
-
1.
Testosterone supplementation and body composition: results from a meta-analysis of observational studies.
Corona, G, Giagulli, VA, Maseroli, E, Vignozzi, L, Aversa, A, Zitzmann, M, Saad, F, Mannucci, E, Maggi, M
Journal of endocrinological investigation. 2016;(9):967-81
Abstract
PURPOSE The concept of testosterone (T) supplementation (TS) as a new anti-obesity medication in men with testosterone deficiency syndrome (TDS) is emerging. Data from placebo-controlled trials are more conflicting. The aim of this study is to systematically review and meta-analyze available observational and register studies reporting data on body composition in studies on TS in TDS. METHODS An extensive MEDLINE, Embase, and Cochrane search was performed including the following words: "testosterone" and "body composition." All observational studies comparing the effect of TS on body weight and other body composition and metabolic endpoints were considered. RESULTS Out of 824 retrieved articles, 32 were included in the study enrolling 4513 patients (mean age 51.7 ± 6.1 years). TS was associated with a time-dependent reduction in body weight and waist circumference (WC). The estimated weight loss and WC reduction at 24 months were -3.50 [-5.21; -1.80] kg and -6.23 [-7.94; -4.76] cm, respectively. TS was also associated with a significant reduction in fat and with an increase in lean mass as well as with a reduction in fasting glycemia and insulin resistance. In addition, an improvement of lipid profile (reduction in total cholesterol as well as of triglyceride levels and an improvement in HDL cholesterol levels) and in both systolic and diastolic blood pressure was observed. CONCLUSIONS Present data support the view of a positive effect of TS on body composition and on glucose and lipid metabolism. In addition, a significant effect on body weight loss was observed, which should be confirmed by a specifically designed RCT.
-
2.
THERAPY OF ENDOCRINE DISEASE: Testosterone supplementation and body composition: results from a meta-analysis study.
Corona, G, Giagulli, VA, Maseroli, E, Vignozzi, L, Aversa, A, Zitzmann, M, Saad, F, Mannucci, E, Maggi, M
European journal of endocrinology. 2016;(3):R99-116
Abstract
OBJECTIVE The role of testosterone (T) in regulating body composition is conflicting. Thus, our goal is to meta-analyse the effects of T supplementation (TS) on body composition and metabolic outcomes. METHODS All randomized controlled trials (RCTs) comparing the effect of TS on different endpoints were considered. RESULTS Overall, 59 trials were included in the study enrolling 3029 and 2049 patients in TS and control groups respectively. TS was associated with any significant modification in body weight, waist circumference and BMI. Conversely, TS was associated with a significant reduction in fat and with an increase in lean mass as well as with a reduction of fasting glycaemia and insulin resistance. The effect on fasting glycaemia was even higher in younger individuals and in those with metabolic diseases. When only RCTs enrolling hypogonadal (total T <12 mol/l) subjects were considered, a reduction of total cholesterol as well as triglyceride (TGs) levels were also detected. Conversely, an improvement in HDL cholesterol levels as well as in both systolic and diastolic blood pressure was not observed. CONCLUSION Our data suggest that TS is able to improve body composition and glycometabolic profile particularly in younger subjects and in those with metabolic disturbances. Specifically designed studies are urgently needed to confirm this point.
-
3.
Testosterone supplementation and sexual function: a meta-analysis study.
Corona, G, Isidori, AM, Buvat, J, Aversa, A, Rastrelli, G, Hackett, G, Rochira, V, Sforza, A, Lenzi, A, Mannucci, E, et al
The journal of sexual medicine. 2014;(6):1577-92
Abstract
INTRODUCTION The role of testosterone supplementation (TS) as a treatment for male sexual dysfunction remains questionable. AIM: The aim of this study was to attempt a meta-analysis on the effect of TS on male sexual function and its synergism with the use of phosphodiesterase type 5 inhibitor (PDE5i). METHODS An extensive Medline, Embase, and Cochrane search was performed. MAIN OUTCOME MEASURES All randomized controlled trials (RCTs) comparing the effect of TS vs. placebo or the effect of TS as add on to PDE5is on sexual function were included. Data extraction was performed independently by two of the authors (A. M. Isidori and G. Corona), and conflicts resolved by the third investigator (M. Maggi). RESULTS Out of 1,702 retrieved articles, 41 were included in the study. In particular, 29 compared TS vs. placebo, whereas 12 trials evaluated the effect of TS as add on to PDE5is. TS is able to significantly ameliorate erectile function and to improve other aspects of male sexual response in hypogonadal patients. However, the presence of possible publication bias was detected. After applying "trim and fill" method, the positive effect of TS on erectile function and libido components retained significance only in RCTs partially or completely supported by pharmaceutical companies (confidence interval [0.04-0.53] and [0.12; 0.52], respectively). In addition, we also report that TS could be associated with an improvement in PDE5i outcome. These results were not confirmed in placebo-controlled studies. The majority of studies, however, included mixed eugonadal/hypogonadal subjects, thus imparting uncertainty to the statistical analyses. CONCLUSIONS TS plays positive effects on male sexual function in hypogonadal subjects. The role of TS is uncertain in men who are not clearly hypogonadal. The apparent difference between industry-supported and independent studies could depend on trial design more than on publication bias. New RCTs exploring the effect of TS in selected cases of PDE5i failure that persistently retain low testosterone levels are advisable.
-
4.
Testosterone and metabolic syndrome: a meta-analysis study.
Corona, G, Monami, M, Rastrelli, G, Aversa, A, Tishova, Y, Saad, F, Lenzi, A, Forti, G, Mannucci, E, Maggi, M
The journal of sexual medicine. 2011;(1):272-83
Abstract
INTRODUCTION Metabolic syndrome (MetS) is often associated with male hypogonadism. Despite the well-known link, the role of testosterone replacement therapy (TRT) in MetS has not been completely clarified. AIM: To systematically analyse the relationship between androgen levels and MetS we performed a review and meta-analyses of available prospective and cross-sectional studies. In addition, a specific meta-analysis on the metabolic effects of TRT in available randomized clinical trials (RCTs) was also performed. METHODS An extensive Medline search was performed including the following words "testosterone,""metabolic syndrome," and "males". MAIN OUTCOME MEASURES Out of 323 retrieved articles, 302 articles were excluded for different reasons. Among the 20 published studies included, 13, 3, and 4 were cross-sectional, longitudinal, and RCTs, respectively. Another unpublished RCT was retrieved on http://www.clinicaltrials.gov. RESULTS MetS patients showed significantly lower T plasma levels, as compared with healthy individuals. Similar results were obtained when MetS subjects with and without erectile dysfunction were analyzed separately or when NCEP-ATPIII MetS criteria were compared with other definitions. Meta-regression analysis demonstrated that type 2 diabetes (T2DM) increased the MetS-associated T fall. In a multiple regression model, after adjusting for age and BMI, both T2DM and MetS independently predicted low testosterone (adj. r = -0.752; P < 0.001 and -0.271; P < 0.05, respectively). Analysis of longitudinal studies demonstrated that baseline testosterone was significantly lower among patients with incident MetS in comparison with controls (2.17 [-2.41;-1.94] nmol/L; P < 0.0001). Combining the results of RCTs, TRT was associated with a significant reduction of fasting plasma glucose, homeostatic model assessment index, triglycerides, and waist circumference. In addition, an increase of high-density lipoprotein cholesterol was also observed. CONCLUSIONS The meta-analysis of the available cross-sectional data suggests that MetS can be considered an independent association of male hypogonadism. Although only few RCTs have been reported, TRT seems to improve metabolic control, as well as central obesity.
-
5.
Type 2 diabetes mellitus and testosterone: a meta-analysis study.
Corona, G, Monami, M, Rastrelli, G, Aversa, A, Sforza, A, Lenzi, A, Forti, G, Mannucci, E, Maggi, M
International journal of andrology. 2011;(6 Pt 1):528-40
Abstract
Several studies suggest that type 2 diabetes mellitus (T2DM) is often associated with male hypogonadism. Despite the well-known link, the role of testosterone replacement therapy (TRT) in T2DM has not been completely clarified. The aim of the present study was to analyse systematically the relationship between androgen levels and T2DM by reviewing and meta-analysing available prospective and cross-sectional studies. In addition, a specific meta-analysis on the metabolic effects of TRT in available randomized clinical trials (RCTs) was performed. An extensive Medline search was performed including the following words: 'testosterone', 'type 2 diabetes mellitus' and 'males'. Of 742 retrieved articles, 37 were included in the study. In particular 28, 5 and 3 were cross-sectional, longitudinal and interventional studies, respectively. A further unpublished RCT was retrieved from http://www.clinicaltrials.gov. T2DM patients showed significantly lower testosterone plasma levels in comparison with non-diabetic individuals. Similar results were obtained when T2DM subjects with and without erectile dysfunction were analysed separately. Meta-regression analysis demonstrated that ageing reduced, while obesity increased, these differences. However, in a multiple regression model, after adjusting for age and body mass index (BMI), T2DM was still associated with lower total testosterone (TT) levels (adjusted r = -0.568; p < 0.0001). Analysis of longitudinal studies demonstrated that baseline TT was significantly lower among patients with incident diabetes in comparison with controls (HR = -2.08[-3.57;-0.59]; p < 0.001). Combining the results of RCTs, TRT was associated with a significant reduction in fasting plasma glucose, HbA1c, fat mass and triglycerides. Conversely, no significant difference was observed for total and high-density lipoprotein cholesterol, blood pressure and BMI. The meta-analysis of the available cross-sectional data suggests that T2DM can be considered independently associated with male hypogonadism. Although only few RCTs have been reported, TRT seems to improve glycometabolic control as well as fat mass in T2DM subjects.