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Emanuela A Greco

Publications and source records attributed to Emanuela A Greco.

6 recordsLinked to original sources

Combining testosterone and PDE5 inhibitors in erectile dysfunction: basic rationale and clinical evidences.

INTRODUCTION: Erectile dysfunction (ED) and decline of testosterone levels are frequently observed with age and also in illnesses with a common basis of endothelial damage. OBJECTIVES: To review molecular mechanisms underlying androgen action upon its receptor and phosphodiesterase type 5 (PDE5) expression and regulation by testosterone in cavernous tissue and their clinical implication in the treatment of ED refractory to PDE5 inhibitors (PDE5-Is). METHODS: From January 2003 to May 2006 [corrected] we performed an extensive, unsystematic MEDLINE literature search reviewing relevant data on basic and clinical studies regarding the efficacy of combination therapies. RESULTS: Most trials using testosterone alone for treatment of ED in hypogonadal men suffer from methodologic problems and report inconsistent results, but overall the trials suggest that testosterone is superior to placebo. Orally effective PDE5-Is, such as sildenafil, tadalafil, or vardenafil, may be ineffective depending on the demonstration of testosterone regulation of PDE5 expression in human corpus cavernous, and their efficacy may be enhanced by testosterone adjunction whenever necessary. CONCLUSIONS: Screening for hypogonadism in all men with ED is necessary to identify men with severe hypogonadism and some cases of mild to moderate hypogonadism, who may benefit from testosterone treatment. Identification of threshold values for testosterone supplementation to appropriately benefit from PDE5-Is failure may improve clinical management of unresponsive patients with minimization of unwanted effects.

3',5'-Cyclic-GMP Phosphodiesterases↗

Testosterone:estradiol ratio changes associated with long-term tadalafil administration: a pilot study.

INTRODUCTION: It has been reported that lack of sexual activity due to erectile dysfunction (ED) may be associated with testosterone (T) decline. AIM: To investigate whether the known changes in sex hormones associated with resumption of sexual activity are sustained in the long term. MAIN OUTCOME MEASURES: Primary endpoints were variations from baseline of steroid hormones: total T, free T (f T), and estradiol (E). Secondary endpoints were variations of erectile function domain scores at International Index of Erectile Function-5 (IIEF-5). METHODS: In an open-label fashion, 20 patients (mean age 54.8 +/- 8.4 years) received tadalafil 10-20 mg on demand for 12 months. Exclusion criteria were those reported for phosphodiesterase inhibitors, including hypogonadism and hyperprolactinemia. RESULTS: Tadalafil assumption was safe and well tolerated (overall adverse effects in 15% of patients) and none discontinued medication. A significant decrease in E levels occurred at the end of the study (from 19.9 +/- 9.6 to 16.6 +/- 8.1 ng/dL, P = 0.042 vs. baseline), with parallel increase in the T:E ratio (26.3 +/- 15.3 to 32.6 +/- 17.7, P = 0.05), whereas no changes in T and f T serum levels were observed, respectively (411.4 +/- 131.4 to 434.2 +/- 177.1 ng/dL and 47.7 +/- 15.3 to 49.9 +/- 19.1 pmol/L, not significant). Interestingly, nonparametric subgroup analysis for related samples revealed that E decrease was detectable only in lean (N = 14) but not in obese (N = 6, body mass index > 27.5 kg/m2) subjects (17.8 +/- 10.1 vs. 13.5 +/- 6.8, P < 0.05). A net increase in IIEF-5 scores was observed at the endpoint (13.7 +/- 5.9 vs. 25.7 +/- 2.9, P < 0.0001). CONCLUSIONS: Sustained improvement in sexual function after 12 months of tadalafil administration is associated with increased T:E ratio mainly related to reduction of E levels. We hypothesize that androgen-estrogen cross-talk and possible inhibition of aromatase activity during chronic exposure to tadalafil might have a role in the regulation of erectile function.

Adult↗

Effects of testosterone on body composition, bone metabolism and serum lipid profile in middle-aged men: a meta-analysis.

OBJECTIVES: Ageing in men is associated with a gradual decline in serum testosterone levels and a concomitant loss of muscle mass, accumulation of central adiposity, impaired mobility and increased risk of bone fractures. Whether androgen treatment might be beneficial in these subjects is still under debate. We have carried out a systematic review of randomized controlled trials (RCTs) evaluating the effects of testosterone (T) administration to middle-aged and ageing men on body composition, muscle strength, bone density, markers of bone metabolism and serum lipid profile. DATA SOURCE: A comprehensive search of all published randomized clinical trials was performed using the MEDLINE, Cochrane Library, EMBASE and Current Contents databases. REVIEW METHODS: Guided by prespecified criteria, software-assisted data abstraction and quality assessed by two independent reviewers, 29 RCTs were found to be eligible. For each investigated variable, we reported the results of pooled estimates of testosterone treatment using the random effect model of meta-analysis. Heterogeneity, reproducibility and consistency of the findings across studies were explored using sensitivity and meta-regression analysis. RESULTS: Overall, 1,083 subjects were evaluated, 625 randomized to T, 427 to placebo and 31 to observation (control group). Weighted mean age was 64.5 years (range 49.9--77.6) and mean serum testosterone was 10.9 nmol/l (range 7.8--19). Testosterone treatment produced: (i) a reduction of 1.6 kg (CI: 2.5--0.6) of total body fat, corresponding to -6.2% (CI: 9.2--3.3) variation of initial body fat, (ii) an increase in fat free mass of 1.6 kg (CI: 0.6--2.6), corresponding to +2.7% (CI: 1.1--4.4) increase over baseline and (iii) no change in body weight. The effects of T on muscle strength were heterogeneous, showing a tendency towards improvement only at the leg/knee extension and handgrip of the dominant arm (pooled effect size=0.3 standard mean difference (SMD), CI: -0.0 to 0.6). Testosterone improved bone mineral density (BMD) at the lumbar spine by +3.7% (CI: 1.0--6.4%) compared to placebo, but not at the femoral neck, and produced a consistent reduction in bone resorption markers (pooled effect size = -0.6 SMD, CI: -1.0 to -0.2). Testosterone also reduced total cholesterol by 0.23 mmol/l (CI: -0.37 to -0.10), especially in men with lower baseline T concentrations, with no change in low density lipoprotein (LDL)-cholesterol. A significant reduction of high density lipoprotein (HDL)-cholesterol was found only in studies with higher mean T-values at baseline (-0.085 mmol/l, CI: -0.017 to -0.003). Sensitivity and meta-regression analysis revealed that the dose/type of T used, in particular the possibility of aromatization, explained the heterogeneity in findings observed on bone density and HDL-cholesterol among studies. CONCLUSION: The present analysis provides an estimate of the average treatment effects of testosterone therapy in middle-aged men. Our findings are sufficiently strong to justify further interventional studies focused on alternative targets of androgenic treatment carrying more stringent clinical implications, in particular the cardiovascular, metabolic and neurological systems.

Adult↗

Effects of testosterone on sexual function in men: results of a meta-analysis.

OBJECTIVES: The role of androgen decline in the sexual activity of adult males is controversial. To clarify whether sexual function would benefit from testosterone (T) treatment in men with partially or severely reduced serum T levels, we conducted a systematic review and meta-analysis of placebo-controlled studies published in the past 30 years. The aim of this study was to assess and compare the effects of T on the different domains of sexual life. DATA SOURCE: A comprehensive search of all published randomized clinical trials was performed in MEDLINE, the Cochrane Library, EMBASE and Current Contents databases. REVIEW METHODS: Guided by prespecified criteria, software-assisted data abstraction and quality assessed by two independent reviewers, a total of 17 randomized placebo-controlled trials were found to be eligible. For each domain of sexual function we calculated the standardized mean difference relative to T and reported the results of pooled estimates of T treatment using the random effect model of meta-analysis. Heterogeneity, reproducibility and consistency of the findings across studies were explored using sensitivity and meta-regression analysis. RESULTS: Overall, 656 subjects were evaluated: 284 were randomized to T, 284 to placebo (P) and 88 treated in cross-over. The median study length was 3 months (range 1-36 months). Our meta-analysis showed that in men with an average T level at baseline below 12 nmol/l, T treatment moderately improved the number of nocturnal erections, sexual thoughts and motivation, number of successful intercourses, scores of erectile function and overall sexual satisfaction, whereas T had no effect on erectile function in eugonadal men compared to placebo. Heterogeneity was explored by grouping studies according to the characteristics of the study population. A cut-off value of 10 nmol/l for the mean T of the study population failed to predict the effect of treatment, whereas the presence of risk factors for vasculogenic erectile dysfunction (ED), comorbidities and shorter evaluation periods were associated with greater treatment effects in the studies performed in hypogonadal, but not in eugonadal, men. Meta-regression analysis showed that the effects of T on erectile function, but not libido, were inversely related to the mean baseline T concentration. The meta-analysis of available studies indicates that T treatment might be useful for improving vasculogenic ED in selected subjects with low or low-normal T levels. The evidence for a beneficial effect of T treatment on erectile function should be tempered with the caveats that the effect tends to decline over time, is progressively smaller with increasing baseline T levels, and long-term safety data are not available. The present meta-analysis highlights the need, and pitfalls, for large-scale, long-term, randomized controlled trials to formally investigate the efficacy of T replacement in symptomatic middle-aged and elderly men with reduced T levels and ED.

Adult↗

Hormonal supplementation and erectile dysfunction.

The role of testosterone on sexual desire is well established. However, the effects of low testosterone levels in the pathophysiology of erectile mechanism in humans remains unclear. Recent evidence indicate that approximately 10-20% of men with erectile dysfunction (ED) have hormonal abnormalities, raising up to 35% over the age of sixty. It is now clear that sexual desire and erectile function in humans are both responsive to androgens, probably at different threshold values. In fact, different degrees of testosterone deficiency may determine a sequence of molecular penile events leading to reduced capacity of penile smooth muscle and endothelial cells of relaxation, without greatly affecting sexual desire. Also, androgens may directly control the expression and activity of phosphodiesterase type-5 in human corpus cavernosum. In some selected men with total testosterone below 10-13nmol/l and/or free testosterone below 200-250pmol/l, androgen supplementation may improve therapeutic efficacy of phosphodiesterase type-5 inhibitors. For ageing men with partial androgen deficiency (PADAM) who fail first-line oral treatments in whom androgens are not contraindicated, a combination of testosterone and phosphodiesterase type-5 inhibitors may be considered to improve erectile function and improve the quality of life.

Androgens↗