Testosterone therapy increases sexual desire in ageing men with low–normal testosterone levels and symptoms of androgen deficiency

Effect of testosterone replacement therapy on lower urinary tract symptoms: A systematic review and network meta-analysis

OBJECTIVE

In this study, we aimed to perform a network meta-analysis (NMA) to investigate the effects of different testosterone replacement therapy (TRT) administration routes on lower urinary tract symptoms (LUTS) in aging men with late-onset hypogonadism (LOH).

METHODS

A systematic search of PubMed, Embase, The Cochrane Library, CNKI, WanFang Data, and VIP was conducted to identify randomized controlled trials (RCTs) reporting data on International Prostate Symptom Score (IPSS), prostate-specific antigen (PSA) level, or prostate volume. NMA was performed, and subgroup analysis was conducted to assess the impact of TRT duration on outcomes.

RESULTS

A total of 21 RCTs involving 2453 participants were included. For pairwise meta-analysis, p values for TRT delivered by transdermal, intramuscular, and oral routes were as follows: IPSS: 0.93, 0.20, and 0.76; PSA level: 0.20, 0.27, and 0.98; prostate volume: 0.18, 0.04, and 0.16. There were no significant differences in IPSS, PSA level, or prostate volume between TRT routes. In subgroup analysis, long-term intramuscular TRT significantly decreased IPSS (p = 0.03), short-term transdermal TRT increased PSA levels (p < 0.001), and short-term intramuscular TRT increased the prostate volume (p = 0.04). Other forms of TRT showed no significant change in IPSS, PSA level, and prostate volume compared with the placebo. Indirect comparison of the three administration routes demonstrated no significant differences in IPSS, PSA level, and prostate volume. Nevertheless, surface under the cumulative ranking curve analysis indicated that intramuscular TRT had an 83% probability of being the best method for decreasing IPSS.

CONCLUSIONS

The results demonstrate that TRT does not worsen LUTS regardless of the administration route. Intramuscular TRT may be the preferred treatment for aging men with LOH and LUTS. Intramuscular TRT may be the preferred treatment for men with LOH and LUTS. Further research is warranted to validate these findings and optimize TRT management strategies.

Testosterone replacement in men with sexual dysfunction

BACKGROUND

Clinical practice guidelines recommend testosterone replacement therapy (TRT) for men with sexual dysfunction and testosterone deficiency. However, TRT is commonly promoted in men without testosterone deficiency and existing trials often do not clearly report participants' testosterone levels or testosterone-related symptoms. This review assesses the potential benefits and harms of TRT in men presenting with complaints of sexual dysfunction.

OBJECTIVES

To assess the effects of testosterone replacement therapy compared to placebo or other medical treatments in men with sexual dysfunction.

SEARCH METHODS

We performed a comprehensive search of CENTRAL (the Cochrane Library), MEDLINE, EMBASE, and the trials registries ClinicalTrials.gov and World Health Organization International Clinical Trials Registry Platform, with no restrictions on language of publication or publication status, up to 29 August 2023.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) in men (40 years or over) with sexual dysfunction. We excluded men with primary or secondary hypogonadism. We compared testosterone or testosterone with phosphodiesterase-5 inhibitors (PDEI5I) to placebo or PDE5I alone.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened the literature, assessed the risk of bias, extracted data, and rated the certainty of evidence (CoE) according to GRADE using a minimally contextualized approach. We performed statistical analyses using a random-effects model and interpreted them according to standard Cochrane methodology. Predefined primary outcomes were self-reported erectile dysfunction assessed by a validated instrument, sexual quality of life assessed by a validated instrument, and cardiovascular mortality. Secondary outcomes were treatment withdrawal due to adverse events, prostate-related events, and lower urinary tract symptoms (LUTS). We distinguished between short-term (up to 12 months) and long-term (> 12 months) outcomes.

MAIN RESULTS

We identified 43 studies with 11,419 randomized participants across three comparisons: testosterone versus placebo, testosterone versus PDE5I, and testosterone with PDE5I versus PDE5I alone. This abstract focuses on the most relevant comparison of testosterone versus placebo. Testosterone versus placebo (up to 12 months) Based on a predefined sensitivity analysis of studies at low risk of bias, and an analysis combing data from the similar International Index of Erectile Function (IIEF-EF) and IIEF-5 instruments, TRT likely results in little to no difference in erectile function assessed with the IIEF-EF (mean difference (MD) 2.37, 95% confidence interval (CI) 1.67 to 3.08; I² = 0%; 6 RCTs, 2016 participants; moderate CoE) on a scale from 6 to 30 with larger values reflecting better erectile function. We assumed a minimal clinically important difference (MCID) of greater than or equal to 4. TRT likely results in little to no change in sexual quality of life assessed with the Aging Males' Symptoms scale (MD -2.31, 95% CI -3.63 to -1.00; I² = 0%; 5 RCTs, 1030 participants; moderate CoE) on a scale from 17 to 85 with larger values reflecting worse sexual quality of life. We assumed a MCID of greater than or equal to 10. TRT also likely results in little to no difference in cardiovascular mortality (risk ratio (RR) 0.83, 95% CI 0.21 to 3.26; I² = 0%; 10 RCTs, 3525 participants; moderate CoE). Based on two cardiovascular deaths in the placebo group and an assumed MCID of 3%, this would correspond to no additional deaths per 1000 men (95% CI 1 fewer to 4 more). TRT also likely results in little to no difference in treatment withdrawal due to adverse events, prostate-related events, or LUTS. Testosterone versus placebo (later than 12 months) We are very uncertain about the longer-term effects of TRT on erectile dysfunction assessed with the IIEF-EF (MD 4.20, 95% CI -2.03 to 10.43; 1 study, 42 participants; very low CoE). We did not find studies reporting on sexual quality of life or cardiovascular mortality. We are very uncertain about the effect of testosterone on treatment withdrawal due to adverse events. We found no studies reporting on prostate-related events or LUTS.

AUTHORS' CONCLUSIONS

In the short term, TRT probably has little to no effect on erectile function, sexual quality of life, or cardiovascular mortality compared to a placebo. It likely results in little to no difference in treatment withdrawals due to adverse events, prostate-related events, or LUTS. In the long term, we are very uncertain about the effects of TRT on erectile function when compared to placebo; we did not find data on its effects on sexual quality of life or cardiovascular mortality. The certainty of evidence ranged from moderate (signaling that we are confident that the reported effect size is likely to be close to the true effect) to very low (indicating that the true effect is likely to be substantially different). The findings of this review should help to inform future guidelines and clinical decision-making at the point of care.

Does activation of oxytocinergic reward circuits postpone the decline of the aging brain?

Oxytocin supports reproduction by promoting sexual- and nursing behavior. Moreover, it stimulates reproductive organs by different avenues. Oxytocin is released to the blood from terminals of oxytocinergic neurons which project from the hypothalamus to the pituitary gland. Concomitantly, the dendrites of these neurons discharge oxytocin into neighboring areas of the hypothalamus. At this location it affects other neuroendocrine systems by autocrine and paracrine mechanisms. Moreover, sensory processing, affective functions, and reward circuits are influenced by oxytocinergic neurons that reach different sites in the brain. In addition to its facilitating impact on various aspects of reproduction, oxytocin is revealed to possess significant anti-inflammatory, restoring, and tranquilizing properties. This has been demonstrated both in many in-vivo and in-vitro studies. The oxytocin system may therefore have the capacity to alleviate detrimental physiological- and mental stress reactions. Thus, high levels of endogenous oxytocin may counteract inadequate inflammation and malfunctioning of neurons and supportive cells in the brain. A persistent low-grade inflammation increasing with age-referred to as inflammaging-may lead to a cognitive decline but may also predispose to neurodegenerative diseases such as Alzheimer's and Parkinson. Interestingly, animal studies indicate that age-related destructive processes in the body can be postponed by techniques that preserve immune- and stem cell functions in the hypothalamus. It is argued in this article that sexual activity-by its stimulating impact on the oxytocinergic activity in many regions of the brain-has the capacity to delay the onset of age-related cerebral decay. This may also postpone frailty and age-associated diseases in the body. Finally, oxytocin possesses neuroplastic properties that may be applied to expand sexual reward. The release of oxytocin may therefore be further potentiated by learning processes that involves oxytocin itself. It may therefore be profitable to raise the consciousness about the potential health benefits of sexual activity particularly among the seniors.

L-Arginine reverses maternal and pre-pubertal codeine exposure-induced sexual dysfunction via upregulation of androgen receptor gene and NO/cGMP signaling

Background

Although codeine has been reported to enhance sexual activity by improving penile reflexes, it has been shown to impair fertility indices. Also, codeine impairs ovarian steroidogenesis and folliculogenesis. Nonetheless, whether or not codeine exerts an epigenetic effect remains unclear. On the other hand, arginine has been speculated to enhance penile reflexes by upregulating NO/cGMP Signaling.

Aim

The study evaluated the effect of maternal codeine exposure and prepubertal codeine and arginine treatments on F1 male sexual function and fertility indices, as well as the outcome of F2 progenies. In addition, the epigenetic programming mechanism was also explored.

Methods

Forty three-week-old female rats were randomized into two groups (n = 20 rats/group); the control that received 0.5 ml of distilled water and the codeine-treated that received 5 mg/kg of codeine via gavage for eight weeks. Afterward, the female rats were paired for mating with sexually mature male rats. Rats were maintained on their pre-pregnancy treatments throughout pregnancy and lactation. FI progenies from each cohort (control and codeine-treated cohorts) were weaned at three weeks and randomized into four groups; the control, codeine-treated, L-arginine-treated (300mg/kg), and codeine + L-arginine-treated (n = 10 rats/group). Administration commenced a week post-weaning and lasted for eight weeks via gavage.

Key findings

Maternal codeine exposure did not alter body weight, but significantly reduced anogenital distance and anogenital index of F1 male offspring. Also, maternal codeine delayed preputial membrane separation, impaired male sexual competence, and penile reflexes of F1 male offsprings. These were associated with reduced dopamine, gonadotropins, and testosterone levels as well as suppressed expression of androgen receptor mRNA. In addition, maternal codeine downregulated NO/cGMP signaling, impaired fertility indices, and reduced the litter size, weight, and survival of F2 progenies. These alterations were observed to be aggravated by prepubertal codeine exposure but improved by prepubertal arginine treatment.

Significance

In conclusion, codeine programmed sexual dysfunction by suppressing the levels of dopamine and testosterone, as well as repressing the expression of androgen receptor mRNA. In addition, codeine-induced epigenetic reprogramming was expressed in the F2 offsprings as reduced litter size and weight, and survival rate. Notably, these observations were worsened by prepubertal codeine exposure, but dampened by prepubertal arginine treatment.

Oxytocin Release: A Remedy for Cerebral Inflammaging

Oxytocin facilitates reproduction both by physiological and behavioral mechanisms. Oxytocinergic neurons emerging from the hypothalamus release oxytocin from the pituitary gland to the blood by axonal discharge to regulate reproductive organs. However, at the same time, oxytocin is secreted into neighboring areas of the hypothalamus from the dendrites of these neurons. Here, the peptide acts by autocrine and paracrine mechanisms to influence other neuroendocrine systems. Furthermore, oxytocinergic neurons project to many different locations in the brain, where they affect sensory processing, affective functions, and reward. Additional to its regulatory role, significant anti-inflammatory and restoring effects of oxytocin have been reported from many invivo and in-vitro studies. The pervasive property of the oxytocin system may enable it generally to dampen stress reactions both peripherally and centrally, and protect neurons and supportive cells from inadequate inflammation and malfunctioning. Animal experiments have documented the importance of preserving immune- and stem cell functions in the hypothalamus to impede age-related destructive processes of the body. Sexual reward has a profound stimulating impact on the oxytocinergic activity, and the present article therefore presents the hypothesis that frequent sexual activity and gratigying social experiance may postpone the onset of frailty and age-associated diseases by neural protection from the bursts of oxytocin. Furthermore, suggestions are given how the neuroplastic properties of oxytocin may be utilized to enhance sexual reward by learning processes in order to further reinforce the release of this peptide.

Androgens and male sexual function

Sexual symptoms are the most specific determinants of low testosterone (T) observed during adulthood. In this narrative review, we summarize the most important evidence supporting the positive relationships between endogenous T levels and sexual activity in the adult male, by using preclinical and clinical observations. In addition, we also report an update of our previous meta-analysis evaluating the effects of T treatment (TRT) on sexual functioning in subjects with T deficiency. Available data indicate that TRT of symptomatic hypogonadal men can improve several aspects of sexual life, including erection. However, the effect is rather modest and lower in subjects with associated metabolic conditions. The specific observed effects are similar to those derived from lifestyle intervention. Since TRT might result in body composition improvement, it is reasonable to suppose that an initial treatment with T can improve the willingness of hypogonadal subjects to perform physical exercise and to adhere to a healthier behavior. Similar data were derived from animal models. However, it should be important to recognize that lifestyle modifications should be the first step to promote weigh reduction. TRT can be combined with lifestyle interventions only in symptomatic hypogonadal subjects especially in the presence of comorbid metabolic conditions.

Testosterone Therapy for Late-Onset Hypogonadism Improves Erectile Function: A Systematic Review and Meta-Analysis

INTRODUCTION

Randomized controlled trials (RCTs) of testosterone therapy (TTh) for late-onset hypogonadism are systematically reviewed and a meta-analysis to assess the efficacy of TTh in improving erectile function is performed.

METHODS

The PubMed, Cochrane Library, and Web of Science databases were searched to identify RCTs published from 2007. RCTs that assessed erectile function using the erectile function domain of the International Index of Erectile Function (IIEF-EFD) were included in the meta-analysis.

RESULTS

The systematic review included 18 RCTs and the meta-analysis included 6 studies that enrolled a total of 1,458 patients. The overall meta-analysis revealed that the IIEF-EFD score was significantly improved in the TTh group compared with the placebo group (mean difference 1.86; 95% confidence interval 1.01-2.72; p < 0.0001). Compared with patients receiving placebo, there was a significant improvement in the IIEF-EFD of patients who received TTh using testosterone gel, those who received TTh for over 30 weeks, and those without diabetes mellitus or metabolic syndrome.

CONCLUSION

TTh achieved a significant improvement in the IIEF-EFD score of hypogonadal men compared with placebo, especially in those who received testosterone gel, were treated for over 30 weeks, and had no comorbidities.

Canadian Urological Association guideline: Erectile dysfunction

Erectile dysfunction (ED) impacts the wellness and quality of life of millions of Canadians. An evaluation focused on the identification of reversible and irreversible underlying factors is recommended for patients presenting with ED. Through a shared decision-making model framework, the goal of ED treatment is to improve functional outcomes and enhance sexual satisfaction while minimizing adverse effects associated with treatment. Given that ED is assessed and treated by multiple different types of health practitioners, the purpose of this guideline is to provide the best available evidence to facilitate care delivery through a Canadian lens. After a narrative review of ED assessment and treatment for general readership, five key clinical questions relating to priority areas of ED are assessed using the GRADE and evidence-to-decision-making frameworks.

Edible Bird's Nest Supplementation Improves Male Reproductive Parameters of Sprague Dawley Rat

Edible bird’s nest (EBN) is reported to have a positive in vitro proliferative effect and contain male reproductive hormones. Spermatogonia cells proliferate during spermatogenesis under male reproductive hormones stimulation that include testosterone, follicle-stimulating hormone (FSH), and luteinizing hormone (LH). Characterization of EBN through liquid chromatography-mass spectrometry (LCMS) has found testosterone as a base peak. Six types of amino acids, estradiol and sialic acid were among the major peaks that have been characterized. Based on the presence of these reproductive components, this study evaluated different doses of EBN on sperm parameters and male reproductive hormones of Sprague Dawley rats. Sixteen Sprague Dawley rats at the age of eight weeks were randomly and equally divided into four groups, which are Control, 10 mg/kg BW/d 50 mg/kg BW/d, and 250 mg/kg BW/d EBN group. The rats were fed with EBN enriched pellet daily and water ad-libitum. Rats were sacrificed and the organ was weighed for organ coefficients after eight weeks of treatment. Sperm concentration, percentage of sperm motility, and sperm viability were evaluated. Meanwhile, ELISA method was used to measure testosterone, FSH, and LH. Findings showed that there were no significant differences in organ coefficient between groups. Supplementation of 250 mg/kg BW/d EBN demonstrated a significant increase in sperm concentration, percentage of sperm motility as well as FSH and LH level compared to 10 mg/kg BW/d group. There was a dose-dependent increase in testosterone level but was not significant between groups. Based on these findings, EBN is concluded to have crucial effects on male reproductive parameters.

Do testosterone supplements enhance response to phosphodiesterase 5 inhibitors in men with erectile dysfunction and hypogonadism: a systematic review and meta-analysis

Background

Combining testosterone and phosphodiesterase 5 inhibitors (PDE5-Is) has become increasingly common in the treatment of men with erectile dysfunction (ED) and low testosterone levels, but combination therapy involving PDE5-Is and testosterone is highly debated, with strong reasons for and against argued by the various opinion leaders. PDE5-Is can be given prior to, alongside or after the commencement of any testosterone replacement therapy. Meanwhile, combination of PDE5-Is and testosterone is reported to better increase testosterone levels and thus improve International Index of Erectile Function (IIEF) score in hypogonadal men. The objective of this meta-analysis was to assess whether testosterone therapy (TTh) can possibly enhance the reaction to PDE5-Is in men with ED and hypogonadism.

Methods

Relevant studies and available data were extensively collected form Medline, Embase, and Cochrane Library databases until June 2019. We calculated standard mean differences (SMDs) with their 95% confidence intervals (CIs) for IIEF including IIEF-5 and IIEF-EFD. Trial sequential analysis (TSA) was performed to explore whether the sample size of the accumulated evidence is sufficient.

Results

There were 8 studies including 913 patients. The pooled SMD of erectile function (EF) component change was 0.663 [(0.299 to 1.027); P<0.0001], which concluded that combination therapy (TTh plus PDE5-Is) is superior to PDE5-Is monotherapy group. We also conducted a subgroup analysis according to trial follow-up, baseline serum total testosterone, baseline EF score and PDE5-Is type, which may explain for the underlying source of heterogeneity in part. The frequency of adverse events and change in PSA levels did not differ between the 2 groups. None of the patients experienced an increase in the prostate specific antigen (PSA) level above 4 ng/mL. Hematocrit increased significantly more in the testosterone group than in the placebo group but not greater than 0.54.

Conclusions

In summary, the present results confirm that combination therapy is effective and safe. TTh can enhance the reaction to PDE5-Is in men with ED and hypogonadism, but this effect also depends on the specific diagnosis and initial response to PDE5-Is. Most patients with adverse events during treatment are mild, and have a stable overall safety of combination therapy.

Efficacy and Safety of Testosterone Treatment in Men: An Evidence Report for a Clinical Practice Guideline by the American College of Physicians

BACKGROUND

Testosterone treatment rates in adult men have increased in the United States over the past 2 decades.

PURPOSE

To assess the benefits and harms of testosterone treatment for men without underlying organic causes of hypogonadism.

DATA SOURCES

English-language searches of multiple electronic databases (January 1980 to May 2019) and reference lists from systematic reviews.

STUDY SELECTION

38 randomized controlled trials (RCTs) of at least 6 months' duration that evaluated transdermal or intramuscular testosterone therapies versus placebo or no treatment and reported prespecified patient-centered outcomes, as well as 20 long-term observational studies, U.S. Food and Drug Administration review data, and product labels that reported harms information.

DATA EXTRACTION

Data extraction by a single investigator was confirmed by a second, 2 investigators assessed risk of bias, and evidence certainty was determined by consensus.

DATA SYNTHESIS

Studies enrolled mostly older men who varied in age, symptoms, and testosterone eligibility criteria. Testosterone therapy improved sexual functioning and quality of life in men with low testosterone levels, although effect sizes were small (low- to moderate-certainty evidence). Testosterone therapy had little to no effect on physical functioning, depressive symptoms, energy and vitality, or cognition. Harms evidence reported in trials was judged to be insufficient or of low certainty for most harm outcomes. No trials were powered to assess cardiovascular events or prostate cancer, and trials often excluded men at increased risk for these conditions. Observational studies were limited by confounding by indication and contraindication.

LIMITATION

Few trials exceeded a 1-year duration, minimum important outcome differences were often not established or reported, RCTs were not powered to assess important harms, few data were available in men aged 18 to 50 years, definitions of low testosterone varied, and study entry criteria varied.

CONCLUSION

In older men with low testosterone levels without well-established medical conditions known to cause hypogonadism, testosterone therapy may provide small improvements in sexual functioning and quality of life but little to no benefit for other common symptoms of aging. Long-term efficacy and safety are unknown.

PRIMARY FUNDING SOURCE

American College of Physicians. (PROSPERO: CRD42018096585).

Health-Seeking Behavior for Erectile Dysfunction in Methadone Maintenance Treatment Patients

Background: Erectile dysfunction (ED) is commonly associated with methadone usage. However, little data is known regarding the health-seeking behavior for ED in the methadone maintenance treatment (MMT) population. This study aimed to determine the health-seeking behavior of MMT patients with ED who perceived themselves as having ED. We aimed to assess the attitudes and health-seeking behavior, the effectiveness of the treatment and the factors associated with treatment-seeking behavior. Methods: This was an observational questionnaire-based study. Patients were first screened for ED (n = 154) using the International Index of Erectile Function-5 (IIEF-5). Fifty patients with ED were evaluated for health-seeking behavior for ED. Results: More than half of the patients who thought they had ED (78%) believed their sex life was affected. Most patients (48%) did not seek any information regarding ED. Education level (p = 0.017) and marital status (p = 0.008) were predictive factors of health-seeking behavior. Conclusions: The health-seeking rate among MMT patients with ED needs to be improved. Measures to increase awareness of ED in MMT patients should be taken to overcome the barrier to health-seeking behavior. Health practitioners should take action to screen ED in this population to increase the detection rate and offer appropriate management according to the patients’ needs.

Transmasculine Hormone Therapy

Prescribing gender-affirming hormonal therapy in transgender men (TM) not only induces desirable physical effects but also benefits mental health. In TM, testosterone therapy is aimed at achieving cisgender male serum testosterone to induce virilization. Testosterone therapy is safe on the short term and middle term if adequate endocrinological follow-up is provided. Transgender medicine is not a strong part of the medical curriculum, although a large number of transgender persons will search for some kind of gender-affirming care. Because hormonal therapy has beneficial effects, all endocrinologists or hormone-prescribing physicians should be able to provide gender-affirming hormonal care.

Testosterone therapy improves erectile function and libido in hypogonadal men

PURPOSE OF REVIEW

Erectile dysfunction and decreased libido are common complaints in the older male population. Recent studies have elucidated the role testosterone therapy (TTh) can play in men with low testosterone levels. The aim of this review is to provide an overview of these findings and the utility of TTh. We specifically examine the role of TTh on erectile function, coadministration with phosphodiesterase type 5 inhibitors, and libido.

RECENT FINDINGS

Recent publications suggest that TTh improves mild erectile dysfunction, though may be less useful in men with more severe erectile dysfunction. In men unresponsive to phosphodiesterase type 5 inhibitors and with mild erectile dysfunction, TTh can further improve erectile function. TTh has also shown consistent benefit in improving libido in men with low testosterone levels at baseline, with no additional improvements once testosterone levels are normalized.

SUMMARY

The available literature supports a role for TTh in men with low testosterone levels, erectile dysfunction, and low libido, with symptomatic improvement in these men.

Benefits and Health Implications of Testosterone Therapy in Men With Testosterone Deficiency

INTRODUCTION

Testosterone (T) deficiency (TD; hypogonadism) has deleterious effects on men's health; negatively affects glycometabolic and cardiometabolic functions, body composition, and bone mineral density; contributes to anemia and sexual dysfunction; and lowers quality of life. T therapy (TTh) has been used for the past 8 decades to treat TD, with positive effects on signs and symptoms of TD.

AIM

To summarize the health benefits of TTh in men with TD.

METHODS

A comprehensive literature search was carried out using PubMed, articles relevant to TTh were accessed and evaluated, and a comprehensive summary was synthesized.

MAIN OUTCOME MEASURES

Improvements in signs and symptoms of TD reported in observational studies, registries, clinical trials, and meta-analyses were reviewed and summarized.

RESULTS

A large body of evidence provides significant valuable information pertaining to the therapeutic value of TTh in men with TD. TTh in men with TD provides real health benefits for bone mineral density, anemia, sexual function, glycometabolic and cardiometabolic function, and improvements in body composition, anthropometric parameters, and quality of life.

CONCLUSION

TTh in the physiologic range for men with TD is a safe and effective therapeutic modality and imparts great benefits on men's health and quality of life. Traish AM. Benefits and Health Implications of Testosterone Therapy in Men With Testosterone Deficiency. Sex Med Rev 2018;6:86-105.

Treatment of Men for “Low Testosterone”: A Systematic Review

Testosterone products are recommended by some prescribers in response to a diagnosis or presumption of “low testosterone” (low-T) for cardiovascular health, sexual function, muscle weakness or wasting, mood and behavior, and cognition. We performed a systematic review of 156 eligible randomized controlled trials in which testosterone was compared to placebo for one or more of these conditions. We included studies in bibliographic databases between January 1, 1950 and April 9, 2016, and excluded studies involving bodybuilding, contraceptive effectiveness, or treatment of any condition in women or children. Studies with multiple relevant endpoints were included in all relevant tables. Testosterone supplementation did not show consistent benefit for cardiovascular risk, sexual function, mood and behavior, or cognition. Studies that examined clinical cardiovascular endpoints have not favored testosterone therapy over placebo. Testosterone is ineffective in treating erectile dysfunction and controlled trials did not show a consistent effect on libido. Testosterone supplementation consistently increased muscle strength but did not have beneficial effects on physical function. Most studies on mood-related endpoints found no beneficial effect of testosterone treatment on personality, psychological well-being, or mood. The prescription of testosterone supplementation for low-T for cardiovascular health, sexual function, physical function, mood, or cognitive function is without support from randomized clinical trials.

Testosterone Treatment and Sexual Function in Older Men With Low Testosterone Levels

CONTEXT

The Testosterone Trials are a coordinated set of seven trials to determine the efficacy of T in symptomatic men ≥65 years old with unequivocally low T levels. Initial results of the Sexual Function Trial showed that T improved sexual activity, sexual desire, and erectile function.

OBJECTIVE

To assess the responsiveness of specific sexual activities to T treatment; to relate hormone changes to changes in sexual function; and to determine predictive baseline characteristics and T threshold for sexual outcomes.

DESIGN

A placebo-controlled trial.

SETTING

Twelve academic medical centers in the United States.

PARTICIPANTS

A total of 470 men ≥65 years of age with low libido, average T <275 ng/dL, and a partner willing to have sexual intercourse at least twice a month.

METHODS

Men were assigned to take T gel or placebo for 1 year. Sexual function was assessed by three questionnaires every 3 months: the Psychosexual Daily Questionnaire, the Derogatis Interview for Sexual Function, and the International Index of Erectile Function.

RESULTS

Compared with placebo, T administration significantly improved 10 of 12 measures of sexual activity. Incremental increases in total and free T and estradiol levels were associated with improvements in sexual activity and desire, but not erectile function. No threshold T level was observed for any outcome, and none of the 27 baseline characteristics predicted responsiveness to T.

CONCLUSIONS

In older men with low libido and low T levels, improvements in sexual desire and activity in response to T treatment were related to the magnitude of increases in T and estradiol levels, but there was no clear evidence of a threshold effect.

Role of androgens in modulating male and female sexual function

Advancement in basic and clinical research has provided considerable evidence suggesting a key role of androgens in the physiology and pathophysiology of sexual function. Evidence from clinical studies in men and women with androgen deficiency support a role of androgens in maintaining sexual function in men and women and are integral in maintaining sexual health. Preclinical studies utilizing male animal models demonstrated a role of androgens in maintenance of: (i) penile tissue structural integrity, (ii) penile trabecular smooth muscle growth and function, (iii) integrity of penile nerve fiber network, (iv) signaling pathways in the corpora cavernosa, (v) myogenic and adipogenic differentiation in the corpora cavernosa, (vi) physiological penile response to stimuli, and (vii) facilitating corporeal hemodynamics. These findings strongly suggest a role for androgen in the physiology of penile erection. In addition, clinical studies in hypogonadal men with erectile dysfunction treated with testosterone provided invaluable information on restoring erectile function and improving ejaculatory function. Similarly, clinical studies in surgically or naturally postmenopausal women with androgen deficiency suggested that androgens are important for maintaining sexual desire and testosterone treatment was shown to improve sexual desire, arousal and orgasm. Furthermore, studies in female animal models demonstrated that androgens maintain the integrity of vaginal nerve fiber network, muscularis volume, and enhance genital blood flow and mucification. Based on the biochemical, physiological and clinical findings from human and animal studies, we suggest that androgens are integral for maintaining sexual function and play a critical role in maintaining sexual health in men and women.

Effects of testosterone on lean mass gain in elderly men: systematic review with meta-analysis of controlled and randomized studies

The objective of this study was to evaluate the effects of steroid anabolic androgenic hormones use on lean mass gain in elderly men through a systematic review with a meta-analysis of randomized controlled studies. We systematically searched PubMed database until 4th October 2013. We included randomized placebo-controlled trials (RCT) that studied testosterone replacement therapy in men over 60 years of age, with total testosterone levels ≤550 ng/dl, observing gains in weight, lean mass tissue and fat mass as outcome. We excluded duplicated studies, studies which mixed men and women, and studies using weak androgens such as dehydroepiandrosterone or androstenedione. The initial search yielded 2681 articles, of which 26 were selected for full text analysis. In the end, 11 studies were included. However, 3 studies were not included in the meta-analysis. Meta-analysis showed that mean weight increased (lean mass), ranging from 1.65 (95 % CI, 1.61-1.69) to 6.20 (95 % CI, 5.22-7.18) kg, although it was heterogeneous (I (2) = 98 %). Effect estimate was 3.59 [2.38-4.81]. Androgen therapy decreased fat mass; effect estimate was -1.78 [-2.57, -0.99] that analysis had also a high level of heterogeneity (I (2) = 81 %). The results suggest that testosterone replacement therapy is able to increase muscle mass in elderly men and that is affected by the time that the treatment is carried out and the method of administration of the drug.

Testosterone supplementation therapy in the treatment of patients with metabolic syndrome

Metabolic syndrome (MetS) comprises a clinical complex of patient risk factors, including increased waist circumference, high triglyceride levels, low high-density lipoprotein cholesterol level, high blood pressure, and insulin resistance, the presence of which increases the likelihood of developing diabetes and cardiovascular disease. With a quarter of the American adult population affected, MetS and type 2 diabetes mellitus have been referred to as the most significant public health threats of the 21st century. Lifestyle modification and weight loss are recommended, however, no specific pharmacologic treatment is known. Given that low levels of testosterone have been implicated in the pathogenesis of MetS and an inverse relationship exists between circulating testosterone levels and the development of MetS, it is tempting to speculate that men with MetS may benefit from testosterone supplementation therapy. As such, our review examines the role of testosterone and the use of testosterone supplementation therapy as a treatment in men with MetS.

Outcomes of testosterone therapy in men with testosterone deficiency (TD): part II

Testosterone (T) deficiency (TD) is a common clinical condition, which contributes to co-morbidities including loss of muscle mass, increased fat mass, increased inflammation, insulin resistance, risk of vascular disease, sexual dysfunction, fatigue, depressed mood and reduced quality of life. T therapy attenuates inflammation, increases insulin sensitivity, muscle mass and reduces fat mass and adiposity. T therapy improves lipid profiles and endothelial function and reduces systolic and diastolic blood pressure. In addition, T therapy may reduce risk of vascular disease and mortality. T therapy improves bone mineral density and increases energy and vitality and improves mood and sexual function and overall quality of life. T therapy appears to be safe if treatment and monitoring are appropriately executed. The evidence available to date does not support alleged concerns regarding risk of cardiovascular disease and prostate cancer. Indeed, T therapy remains controversial. The data in the contemporary literature suggest that T therapy reduces cardiovascular risk and fears promoted by some recent studies should be re-evaluated. The cardiovascular risk and mortality with T therapy must await large prospective controlled clinical trials, which depend on many complex factors. Such studies may be prohibitive in the current environment due to logistical challenges, such as recruiting large number of men to be treated for long-durations with appropriate follow-up, requiring astronomical cost.

Adverse health effects of testosterone deficiency (TD) in men

Testosterone and its metabolite, 5α-dihydrotestosterone are critical metabolic and vascular hormones, which regulate a host of biochemical pathways including carbohydrate, lipid and protein metabolism and modulate vascular function. Testosterone deficiency (TD) is a well-recognized medical condition with important health implications. TD is associated with a number of co-morbidities including increased body weight, adiposity and increased waist circumference, insulin resistance (IR) and type 2 diabetes mellitus (T2DM), hypertension, inflammation, atherosclerosis and cardiovascular disease, erectile dysfunction (ED) and increased incidence of mortality. In this review, we summarize the data in the literature on the prevalence of TD and its association with the various co-morbidities and suggest that T therapy is necessary to improve health outcomes in men with TD.

Predictors of sexual dysfunction incidence and remission in men

INTRODUCTION

The progress and determinants of sexual dysfunction in middle-aged and elderly men remain unclear.

AIM

To describe the incidence or remission and biopsychosocial predictors of erectile dysfunction (ED) and low sexual desire (SD).

MAIN OUTCOME MEASURES

Erectile function (International Index of Erectile Function) and sexual desire (Sexual Desire Inventory 2) were assessed at follow-up. Sociodemographic, lifestyle, and health-related factors were examined in multivariate models of ED and low SD.

METHODS

Data were collected from 810 randomly selected men residing in northern and western Adelaide, Australia, and aged 35-80 years at baseline, who made clinic visits 5 years apart.

RESULTS

At baseline, 23.2% (n = 123) of men had ED. ED incidence and remission were observed in 31.7% (n = 179) and 29.0% (n = 71) of eligible men, respectively. At baseline, 19.2% (n = 165) had low solitary sexual desire, and 6.0% (n = 50) had low dyadic sexual desire; incidence of low sexual desire occurred in 17.6% (n = 83) (solitary) and 8.3% (n = 51) (dyadic), while remission occurred in 15.4% (n = 68) (solitary) and 22.6% (n = 40) (dyadic) of men. In the final regression models, predictors of incident ED were higher age, lower income, higher abdominal fat mass, low alcohol intake, higher risk of obstructive sleep apnea (OSA) risk, voiding lower urinary tract symptoms (LUTS), depression, and diabetes. Predictors of ED remission were lower age, current employment, and absence of voiding LUTS, angina, diabetes, and dyslipidemia. Predictors of low dyadic SD incidence included higher age, never having been married, widowhood, being unemployed, being retired, insufficient physical activity, and low alcohol intake. Predictors of low dyadic SD remission were being married, not being widowed, higher income, lower abdominal fat mass, lower OSA risk, and higher plasma testosterone. Predictors of low solitary SD included never having been married, being unemployed, low alcohol intake, lower testosterone, storage LUTS, and hypertension. Predictors of low solitary SD remission were being married, being employed, higher income, higher physical activity, moderate alcohol intake, and depression.

CONCLUSIONS

Sexual dysfunction in aging men is a dynamic disorder whose incidence and remission are predicted by a range of modifiable risk factors.

Erectile dysfunction and the internet: drug company manipulation of public and professional opinion

Given that the Internet is now a major source of information regarding health and mental health problems, and that it is in the interest of the pharmaceutical industry to influence public and professional opinion, this study evaluated 70 websites about erectile dysfunction. The 31 drug company-funded websites (44%) were, compared with the 39 websites that are not industry funded, significantly more biased toward biological factors in general, and toward medication in particular (p < .01). The high proportion of websites that are industry sponsored, and the bias of those websites, confirms previous studies on depression, posttraumatic stress disorder, schizophrenia, and attention deficit hyperactivity disorder, and demonstrates that drug companies are using their financial might to manipulate public and professional opinion on the Internet.

Do low testosterone levels contribute to ill-health during male ageing?

Testosterone regulates male sexual development and body composition. In adult men, testosterone levels exhibit a gradual decline with increasing age. Whether it is age per se or health and behaviour related factors that are responsible for this decline, and the implications thereof for subsequent health remain controversial. Observational studies report associations of lower testosterone levels with poorer health outcomes in ageing men, including frailty, reduced sexual activity, insulin resistance and cardiovascular events and mortality. However, outcome data from randomised clinical trials of testosterone are limited, and are lacking for major endpoints such as cardiovascular events. The risks and benefits of testosterone intervention in older men require further clarification. This article will review the role of testosterone in men, discuss epidemiological and interventional data illuminating its potential role to preserve health during male ageing, consider the limitations of the evidence base and implications for clinical practice, and explore future directions for research in this topical area.

Standard operational procedures for low sexual desire in men

INTRODUCTION

Low sexual desire in men is a condition that has received little attention; nevertheless it occurs with high frequency. Clinicians are in need of clear guidelines to address this problem.

AIM

To develop standardized operational procedures to be implemented with men presenting low sexual desire/interest (LSD/I).

METHODS

Review of relevant evidence-based literature and published guidelines, integrated with expert opinion.

MAIN OUTCOME

Operational procedures for LSD/I that are recommended for clinical practice with various degrees of support from published evidence.

RESULTS

A new classification scheme is proposed; LSD/I is proposed as an umbrella term for which hypoactive sexual desire disorder (HSDD) is only a subtype. The following standard operational procedures are described: (i) Detection of LSD/I: screening for LSD/I, screening for LSD/I in patients with other sexual dysfunctions; (ii) Diagnosis and assessment of etiology: diagnostic criteria for LSD/I, assessment of depression status, assessment of relationship status, assessment of endocrinologic status, diagnostic criteria for HSDD in men; (iii)

TREATMENT

treatment of LSD/I secondary to low testosterone, treatment of LSD/I secondary to elevated prolactin, treatment of LSD/I secondary to other endocrinologic disorders, treatment of LSD/I secondary to depressive illness and or anxiety disorders, treatment of LSD/I secondary to relationship conflict and treatment of HSDD. A diagnostic and treatment algorithm is presented.

CONCLUSIONS

LSD/I is a common condition that should be identified in patients; it is recommended that this condition be actively investigated by the clinician. Once the diagnosis of LSD/I in men is confirmed, a thorough search for possible causes needs to include both biological and psychological causes. TREATMENT should be etiologically oriented.

Hormones and health outcomes in aging men

Increasing age is a predictor of ill-health and mortality related to cardiovascular disease and to frailty, a syndrome characterized by deterioration of multiple organ systems leading to loss of physiological reserve, diminished capacity to cope with stressors, and increased risk of disability and death. As men grow older, their levels of testosterone decline while the prevalence of ill-health increases. Observational studies have linked lower testosterone levels with cardiovascular disease and mortality in middle-aged and older men. More recently, lower testosterone has been shown to predict reduced sexual activity and frailty in aging men. Additional studies are needed to determine whether lower testosterone is a biomarker or a potentially treatable risk factor for poorer health outcomes in older men. During aging, the response of the pituitary-thyroid axis alters to manifest higher thyrotropin levels. The presences of subclinical hypo- and hyper-thyroidism predict adverse cardiovascular outcomes. Newer results indicate that in euthyroid older men, differences in free thyroxine levels within the normal range predict specific health outcomes including frailty. Clarification of the roles of endogenous testosterone and thyroxine in the genesis of ill-health during male aging offers the prospect of future intervention to preserve health and well-being in this growing population.

Diagnosis and treatment of sexual dysfunctions in late-onset hypogonadism

Testosterone is the principal androgen in the human male. The decline of testosterone with aging was recognized to be associated with a number of symptoms and signs that reduce the quality of life and that may even have severe, debilitating consequences. Clinically, late-onset hypogonadism (LOH) is diagnosed by use of biochemical and clinical measures. Despite published guidelines and recommendations, however, uncertainty surrounds the profile of clinical symptoms as well as the biochemical threshold of diagnosis. Clinicians should be aware of these shortcomings while adhering to the guidelines. Current treatment methods are centered on restoring testosterone to mid to lower levels of young men with natural testosterone replacements. Although recent studies have highlighted possible additional benefits involving improvement of systemic disorders, the goal of treatment is to improve sexual function, while observing for adverse effects in the prostate. Overall, the problem of LOH in debilitating the quality of life and well-being is real, and by following proper guidelines with attentiveness to the results of treatment trials, testosterone replacement therapy presents a safe and effective treatment option.

Hypogonadism and metabolic syndrome

BACKGROUND

The relationship between metabolic syndrome (MetS), male hypogonadism and their possible interaction in cardiovascular (CV) risk stratification are not completely understood.

AIM

We reviewed relationships between testosterone (T) and MetS emphasizing their possible interaction in the pathogenesis of CV diseases.

MATERIALS AND METHODS

A systematic search of published evidence was performed using Medline (1969 to January 2011).

RESULTS

Cross-sectional data have shown that subjects with MetS have lower levels of total T (TT) (about 3 nmol/l), as hypogonadism is more evident in subjects with than in those without erectile dysfunction (ED) than in those without. Longitudinal evidence shows that low T is allocated with a higher risk of subsequent development of MetS, although the reverse condition is also possible. Which are the factors in MetS responsible for the low T is not completely clarified. In clinical studies, increased waist circumference is the major determinant of MetS-associated hypogonadism. Our experiments in rabbits do not support the idea that visceral fat is the main determinant of MetS-associated male hypogonadism. Only few randomized clinical trials have evaluated the impact of T replacement therapy (TRT) in patients with MetS. Available evidence suggests that TRT decreases visceral fat accumulation and ameliorates insulin sensitivity, whereas androgen deprivation increases abdominal adiposity.

CONCLUSIONS

The clinical significance of the MetS-associated hypogonadism needs further clarifications. In particular, it has not been completely clarified if low T might be considered a cause or a consequence of MetS. The benefit of TRT in term of the reduction of CV risk needs to be confirmed in larger and longer studies.

Waist-to-height ratio as a predictor of serum testosterone in ageing men with symptoms of androgen deficiency

The decline in serum testosterone in ageing men may be mediated in part by obesity; however, it is uncertain which measure of adiposity is most closely associated with testosterone levels. We have examined the relationships of age, adiposity and testosterone levels in ageing men with symptoms consistent with hypoandrogenism but who were otherwise in good health. We conducted a cross-sectional study of non-smoking men aged ≥ 54 years recruited from the community and who were free of cancer or serious medical illness. Height (Ht), weight and waist circumference (WC) were measured, and body mass index (BMI) and waist-to-height (WHt) ratio were calculated. Two morning blood samples were collected for measurement of total testosterone (TT), sex hormone binding globulin (SHBG) and luteinizing hormone (LH). Free testosterone (cFT) was calculated. Multivariate linear regression analysis was performed to assess their relationship with measures of adiposity. Two hundred and seven men aged 54-86 years were studied. On univariate analysis WHt ratio was more strongly correlated with TT and cFT than either WC or BMI. Furthermore, in models of TT and cFT, the addition of Ht to WC resulted in an increase in the magnitude of the regression coefficients for both WC (inverse correlate) and Ht (positive correlate), with the contributions of both WC and Ht both being significant (P<0.05 for all). In conclusion, WHt ratio is the best anthropometric predictor of both TT and cFT in this group of healthy but symptomatic ageing men.

Testosterone Replacement Therapy in Males With Erectile Dysfunction

Erectile dysfunction (ED) is defined as the inability to achieve or maintain an erection sufficient for satisfactory sexual performance. Endogenous testosterone is critical for normal libido; however, studies have also demonstrated a potentially important role with respect to the erectile process. The prevalence of testosterone deficiency ranges from 1.7% to 35% in patients with ED, and age is a common factor linking ED and testosterone deficiency. By 2025, global estimates are that there will be 356 million men >65 years. Age-associated testosterone deficiency is characterized by symptoms such as ED, and low serum testosterone. Randomized, placebo controlled studies have established the utility of testosterone replacement therapy (TRT) for the restoration of serum testosterone levels to the normal range in hypogonadal males; however, well designed studies are limited with respect to specific evaluation of the role of TRT as monotherapy in improving erectile function. In addition, recent literature suggests a possible role for TRT in combination with phosphodiesterase-5 (PDE-5) inhibitors for men with ED. The following review describes the potential roles of testosterone in erectile physiology, examines the relationship between testosterone deficiency and ED, and reviews published literature evaluating the use of TRT in hypogonadal males with a diagnosis of ED.