Coadministration of anastrozole sustains therapeutic testosterone levels in hypogonadal men undergoing testosterone pellet insertion

Testosterone deficiency in male organ transplant recipients

Testosterone deficiency is known to affect men with increasing incidence throughout their lifespan. The clinical manifestations of testosterone deficiency, in turn, negatively impact men's quality of life and perception of overall health. The interaction of chronic systemic disease and androgen deficiency represent an area for potential intervention. Here, we explore the topic of testosterone deficiency amongst men with end-stage organ failure requiring transplantation in order to elucidate the underlying pathophysiology of androgen deficiency of chronic disease and discuss whether intervention, including testosterone replacement and organ transplantation, improve patients' outcomes and quality of life.

Clinical application of aromatase inhibitors to treat male infertility

BACKGROUND

Infertility affects 15% of men and contributes to nearly half of all cases of infertility. Infertile men usually have impaired spermatogenesis, presenting as azoospermia or various degrees of asthenospermia and oligozoospermia. Spermatogenesis is a complex and coordinated process, which is under precise modulation by the hypothalamic-pituitary-gonadal (HPG) axis. An aberrant hormone profile, especially an imbalance between testosterone (T) and estradiol (E2), plays an essential role in male infertility. In the male, E2 is produced mainly from the conversion of T by the aromatase enzyme. Theoretically, reducing an abnormally elevated T:E2 ratio using aromatase inhibitors (AIs) could restore the balance between T and E2 and optimize the HPG axis to support spermatogenesis. For decades, AIs have been used to treat male infertility empirically. However, owing to the lack of large-scale randomized controlled studies and basic research, the treatment efficacy and safety of AIs in male infertility remain controversial. Therefore, there is a need to summarize the clinical trials and relevant basic research on the application of AIs in the treatment of male infertility.

OBJECTIVE AND RATIONALE

In this narrative review, we summarized the application of AIs in the treatment of male infertility, including the pharmacological mechanisms involved, clinical trials focused on patients with different types of infertility, factors affecting treatment efficacy and the side-effects.

SEARCH METHODS

A literature search was performed using MEDLINE/PubMed and EMBASE, focusing on publications in the past four decades concerning the use of AIs for treating male infertility. The search terms included AI, male infertility, letrozole, anastrozole, testolactone, azoospermia, oligozoospermia, aromatase polymorphisms, obesity and antiestrogens, in various combinations.

OUTCOMES

Clinical studies demonstrate that AIs, especially nonsteroidal letrozole and anastrozole, could significantly inhibit the production of E2 and its negative feedback on the HPG axis, resulting in increased T and FSH production as well as improved semen parameters in infertile men. Large-scale surveys suggest that obesity may result in symptoms of hypogonadism in both fertile and infertile males, such as decreased semen quality and attenuated sexual function, which can be improved by AIs treatment. Polymorphisms of the aromatase gene CYP19A1, including single nucleotide polymorphisms and tetranucleotide TTTA repeats polymorphism (TTTAn), also influence hormone profiles, semen quality and treatment efficacy of AIs in male hypogonadotropic hypogonadism and infertility. The side-effects of AIs in treating male infertility are various, but most are mild and well tolerated.

WIDER IMPLICATIONS

The application of AIs in treating male infertility has been off-label and empirical for decades. This narrative review has summarized the target patients, dose, treatment duration and side-effects of AIs. Polymorphisms of CYP19A1 that may affect AIs treatment efficacy were also summarized, but a full understanding of the mechanisms involved in AIs action requires further study.

The Utilization and Impact of Aromatase Inhibitor Therapy in Men With Elevated Estradiol Levels on Testosterone Therapy

INTRODUCTION

Testosterone therapy (TTH) for testosterone deficiency (TD) may lead to elevated estradiol (E2) levels requiring management to avoid unnecessary adverse effects.

AIM

To examine the impact of aromatase inhibitors, specifically anastrozole (AZ), in men with elevated E2 on TTH.

METHODS

All patients on TTH at a high volume sexual medicine practice between 2005 and 2019 were reviewed. Men with E2 levels >60 pg/mL regardless of symptoms or 40-60 pg/mL with subjective symptoms were started on AZ 0.5 mg 3x/week. Routine hormone profile and symptom assessment were completed to ensure symptom resolution, reduction of E2 levels and maintenance of testosterone levels. Multivariable logistic regression was completed to determine predictors of men more likely to respond to therapy.

MAIN OUTCOME MEASURE

Demographic and hormonal profiles of men on AZ and predictors of response to therapy.

RESULTS

1708 men with TD were placed on TTH. Of these, 51 (3%) were treated with AZ (AZ+). After exclusions, 44 (2.6%) had elevated estradiol levels >60 pg/mL or >40 pg/mL with symptoms. Demographics were similar between groups. TTH distribution between groups was different with greater rates of topical TTH in the AZ- groups (AZ+:34.1% vs AZ-:53.5%) and greater rates of intramuscular TTH in the AZ+ group (AZ+:38.6% vs AZ-:18.5%) (P = .017 overall). Of the 44 men treated with AZ, 68.0% had pre-AZ E2 levels ≥60 pg/mL and 32.0% had levels between 40 and 60 pg/mL. Median pre-AZ E2 levels were 65 (interquartile range [IQR], 55-94) pg/mL in comparison to 22 (IQR 15-38) pg/mL post-AZ E2 levels (P < .001). Total testosterone levels were similar before and after AZ use (616 (IQR 548-846) ng/dL and 596 (IQR 419-798) ng/dL, respectively, P = .926). No statistically significant predictive factors of E2 reduction using AZ were found.

CONCLUSION

While no statistically significant predictors for E2 recovery in men on AZ were found, AZ remains a reasonable option for E2 reduction in men with elevated levels on TTH. Punjani N, Bernie H, Salter C, et al. The Utilization and Impact of Aromatase Inhibitor Therapy in Men With Elevated Estradiol Levels on Testosterone Therapy. Sex Med 2021;9:100378.

Androgen receptors beyond prostate cancer: an old marker as a new target

Androgen receptors (ARs) play a critical role in the development of prostate cancer. Targeting ARs results in important salutary effects in this malignancy. Despite mounting evidence that ARs also participate in the pathogenesis and/or progression of diverse tumors, exploring the impact of hormonal manipulation of these receptors has not been widely pursued beyond prostate cancer. This review describes patterns of AR expression in a spectrum of cancers, and the potential to exploit this knowledge in the clinical therapeutic setting.

Alternative treatment modalities for the hypogonadal patient

Testosterone (T) deficiency syndrome (TDS) is a prevalent condition, commonly managed with exogenous T. Despite an abundance of T formulations, alternative treatments are often sought for various reasons. To evaluate outcomes of alternative therapies, a PubMed search was performed of all publications that included men with TDS from 1990 through October 2013, with results summarized. Proposed mechanisms of action were also reviewed to provide a pathophysiologic basis for reported outcomes. Nonpharmacologic therapies that increase endogenous T are weight loss, exercise, and varicocelectomy, while medications used off-label include aromatase inhibitors, human chorionic gonadotropin, and selective estrogen receptor modulators. All reported therapies increase T, while changes in estradiol and adverse events vary by therapeutic class. Although limited data preclude direct comparisons between therapies, exercise and weight loss alone or in combination with medications may be considered first line. The role for surgical therapy in TDS remains undefined and requires further study.

A Review of Testosterone Pellets in the Treatment of Hypogonadism

Currently, the most popular form of testosterone replacement is the topical gels that require daily applications and incur a risk of transfer of testosterone to partners and family. One of the problems with testosterone replacement is the short half-life of testosterone. A long-acting formulation is appealing to patients and physicians. In 1972, fused crystalline testosterone pellets were approved in the USA by the FDA but they were not marketed until 2008. Pharmacokinetics studies were available on a different formulation from which much can be learned and applied to the current formulation, Testopel®. The decay kinetics, pituitary suppression, and effect on other sex steroids are reviewed as well as the short-term complication rates. This review should provide the testosterone pellet implanter a better understanding of the physiology of testosterone pellet supplementation for hypogonadism.

Serum testosterone levels and mortality in men with CKD stages 3-4

BACKGROUND

Hypogonadism in men (total testosterone <350 ng/dL) is associated with higher risk of cardiovascular disease and mortality in men on dialysis therapy. We evaluated the association of hypogonadism with all-cause mortality in men with non-dialysis-dependent chronic kidney disease (CKD).

STUDY DESIGN

Retrospective, cohort study.

SETTING & PARTICIPANTS

2,419 men with CKD stages 3-4 (estimated glomerular filtration rate, 15-59 mL/min/1.73 m2) who had total testosterone measured for cause between January 1, 2005, and October 31, 2011, at a tertiary-care center in Cleveland, OH.

PREDICTORS

Total testosterone measured using an immunoassay measurement in 3 forms: (1) categorized as low or testosterone replacement therapy versus normal, (2) continuous log testosterone, and (3) quintiles (100-226, 227-305, 306-392, 393-511, and 512-3,153 ng/dL).

OUTCOMES

Factors associated with low total testosterone level and the association between low total testosterone level and all-cause mortality were evaluated using logistic regression, Cox proportional hazard models, and Kaplan-Meier survival curves.

RESULTS

Hypogonadism was found in 1,288 of 2,419 (53%) men. In a multivariable logistic regression analysis, African American ethnicity and higher estimated glomerular filtration rate were associated with lower odds of having hypogonadism. Diabetes and higher body mass index were associated with higher odds of having hypogonadism. 357 of 2,419 (15%) patients died during a median follow-up of 2.3 years. In the multivariate Cox model, testosterone level <350 ng/dL or testosterone replacement therapy was not associated with mortality. In a multivariable model also adjusted for testosterone supplementation, higher log testosterone was associated with significantly lower mortality (HR per 1 log unit, 0.70; 95% CI, 0.55-0.89). When compared to the highest quintile, the second lowest quintile of testosterone was associated with higher mortality (HR, 1.53; 95% CI, 1.09-2.16).

LIMITATIONS

Single-center study, timing of testosterone testing, lack of adjustment for proteinuria, and sampling bias.

CONCLUSIONS

Low total testosterone level may be associated with higher mortality in men with CKD stages 3-4, but more studies are needed.