Short-term effects of intramuscular and transdermal testosterone on bone turnover, prostate symptoms, cholesterol, and hematocrit in men over age 70 with low testosterone levels

Late-onset Hypogonadism: Bone health

BACKGROUND

Bone health is underdiagnosed and undermanaged in men. Bone loss occurs in men with hypogonadism and in aging men. Thus, patients with a diagnosis of late-onset hypogonadism (LOH) are at risk of osteoporosis and osteoporotic fractures.

OBJECTIVES

To provide an update on research data and clinical implications regarding bone health in men with LOH by reviewing literature articles on this issue.

MATERIALS AND METHODS

A thorough search of listed publications in PubMed on bone health in older men with hypogonadism was performed, and other articles derived from these publications were further identified.

RESULTS

Late-onset Hypogonadism may be associated with reduced bone mineral density (BMD). In a pathophysiological perspective, the detrimental effects of testosterone (T) deficiency on BMD are partly ascribed to relative estrogen deficiency and both serum T and serum estradiol (E2) need to be above 200 ng/dL and 20 pg/mL to prevent bone loss. The effects of exogenous T on BMD are controversial, but most of the studies confirm that testosterone replacement therapy (TRT) increases BMD and prevents further bone loss in men with hypogonadism. No data are available on TRT and the prevention of fractures.

DISCUSSION AND CONCLUSION

In men with documented LOH, a specific clinical workup should be addressed to the diagnosis of osteoporosis in order to program subsequent follow-up and consider specific bone active therapy. TRT should be started according to guidelines of male hypogonadism while keeping in mind that it may also have positive effects also on bone health in men with LOH.

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.

Osteoporosis in Men

The prevalence of osteoporosis is estimated to be 18% in men, but 30% of all fractures occur in men. With age, men experience a gradual decline in testosterone production and bone density. The rate of trabecular bone loss in the lumbar spine in men over age 50 can be double the rate of loss in men under age 50. Endogenous testosterone, estradiol, and their metabolites play a role in maintaining bone health, but their specific effects on bone turnover have been difficult to elucidate. Recently, large cohort studies have provided more detailed information confirming estrogen’s associations and further characterizing the effect of endogenous testosterone and its metabolites on bone mineral density and fractures. Very few clinical trials have assessed the impact of testosterone replacement therapy (TRT) on bone density and fractures in men. The few studies that have been conducted are generally small and not robust enough to show the true treatment effect of TRT and adequately determine its safety. In the absence of data on patient outcomes, it is important for pharmacists to understand the impact of drug therapy on biomarkers and surrogate markers of disease for optimal pharmacotherapy selection and monitoring.

Cross-sectional analysis of testosterone therapies in hypopituitary men on stable pituitary hormone replacement

OBJECTIVE

The last decade has seen a proliferation in options for testosterone replacement. However, little is known as to the benefits of different treatment modalities. Our objective was to determine the testosterone prescription pattern and to examine the impact on various outcome measures.

SUBJECTS AND METHODS

A total of 816 adult-onset hypopituitary males on stable pituitary replacement for at least 1 year were identified from the KIMS database. Patients were classified as either eugonadal (n = 106), or hypogonadal (n = 710) on intramuscular (IM, n = 558), oral (n = 74), transdermal (n = 61), and depot (n = 17) testosterone.

RESULTS

After 1 year of stable pituitary replacement therapy, body composition, cardiovascular parameters, GH replacement and quality of life were not significantly different in androgen-replaced hypogonadal patients compared to eugonadal patients. There were no differences in outcome variables within the hypogonadal group according to the testosterone replacement regimen used and no difference in response to GH therapy.

CONCLUSIONS

The majority of hypopituitary patients in the last decade have received IM testosterone. Body composition, cardiovascular parameters, GH replacement and quality of life were not different between eugonadal and hypogonadal patients and were not differentially affected by the mode of testosterone replacement. These findings are reassuring that there is no major difference in response to different testosterone replacement regimens.

Oral testosterone replacement in symptomatic late-onset hypogonadism: effects on rating scales and general safety in a randomized, placebo-controlled study

OBJECTIVE

To investigate the effects of oral testosterone undecanoate (TU) on symptoms associated with late-onset hypogonadism (LOH). Design Multicenter, randomized, double-blind, placebo-controlled.

METHODS

The study was performed in 14 study centers in seven European countries. Men > or =50 years (n=322) with symptoms of hypogonadism and testosterone deficiency (calculated free testosterone <0.26 nmol/l) were randomized and treated for 12 months with placebo or oral TU 80, 160 or 240 mg/day. Primary outcome was the total score on the Aging Males' Symptoms (AMS) rating scale after six months of treatment.

RESULTS

Treatment of mild-to-moderate LOH symptoms in subjects with borderline hypogonadism with oral TU resulted in an improved total AMS score at month 6, but differences between groups were not statistically significant. There was greater improvement in subjects <60 years when compared with subjects > or =60 years (P=0.001), but baseline testosterone level had no influence on treatment response. The AMS sexual symptoms domain improved with oral TU 160 mg/day at months 6 (P=0.008) and 12 (P=0.012) compared with placebo, but not with 80 and 240 mg/day. Treatment was well-tolerated and there were no between-group differences in adverse events or drop-out rates.

CONCLUSIONS

In one of the largest placebo-controlled studies of testosterone therapy in LOH, oral TU did not improve total AMS score in subjects with mild-to-moderate symptoms compared with placebo, except the sexual symptom sub-domain where a modest improvement was reported with oral TU 160 mg/day.

ISA, ISSAM, EAU, EAA and ASA recommendations: investigation, treatment and monitoring of late-onset hypogonadism in males

The new ISA, ISSAM, EAU, EAA and ASA recommendations on the investigation, treatment and monitoring of late-onset hypogonadism in males provide updated evidence-based information for clinicians who diagnose and treat patients with adult onset, age related testosterone deficiency.

Testosterone for the aging male; current evidence and recommended practice

An international consensus document was recently published and provides guidance on the diagnosis, treatment and monitoring of late-onset hypogonadism (LOH) in men. The diagnosis of LOH requires biochemical and clinical components. Controversy in defining the clinical syndrome continues due to the high prevalence of hypogonadal symptoms in the aging male population and the non-specific nature of these symptoms. Further controversy surrounds setting a lower limit of normal testosterone, the limitations of the commonly available total testosterone result in assessing some patients and the unavailability of reliable measures of bioavailable or free testosterone for general clinical use. As with any clinical intervention testosterone treatment should be judged on a balance of risk versus benefit. The traditional benefits of testosterone on sexual function, mood, strength and quality of life remain the primary goals of treatment but possible beneficial effects on other parameters such as bone density, obesity, insulin resistance and angina are emerging and will be reviewed. Potential concerns regarding the effects of testosterone on prostate disease, aggression and polycythaemia will also be addressed. The options available for treatment have increased in recent years with the availability of a number of testosterone preparations which can reliably produce physiological serum concentrations.

Management of the cardinal features of andropause

There are several problems facing aging men, especially sexual dysfunction, hypogonadism, and psychologic changes. This constellation of changes is sometimes referred to as "manopause" or "andropause." Unlike the dramatic changes in the hormonal milieu occurring during menopause in women, the age-related changes in reproductive hormones of men are subtle and occur gradually throughout the years of mature life. It has been estimated that circulating testosterone (T) declines longitudinally from age 19 at an average rate of 1% per year. The free or dialyzable fraction of serum T and the bioavailable (the sum of free fraction and loosely bound to albumin fraction) T decline more rapidly with age. Although the essential role of androgens in reproductive tissue development and emergence of secondary sex characteristics is well known, their role in adult sexual function seems to be primarily facultative. The effect of T on the central nervous system extends beyond sexual behavior. T has been shown to alter mood, memory, ability to concentrate, and the overall sense of vigor and well being that may interact with a host of other psychologic changes associated with aging. Disordered erectile function is not generally an endocrine problem but rather vascular, neurologic, and psychogenic in origin. It also may be the first sign of systemic vascular disease. The clinical management of andropause requires an individualized approach. In some men, the main problem may be psychologic, whereas in others, hypogonadism may play an important role. Many with erectile failure, suffer silently regardless of its etiology. In this review, we suggest some practical guidelines for the management of these conditions.

The decline of androgen levels in elderly men and its clinical and therapeutic implications

Aging in men is accompanied by a progressive, but individually variable decline of serum testosterone production, more than 20% of healthy men over 60 yr of age presenting with serum levels below the range for young men. Albeit the clinical picture of aging in men is reminiscent of that of hypogonadism in young men and decreased testosterone production appears to play a role in part of these clinical changes in at least some elderly men, the clinical relevancy of the age-related decline in sex steroid levels in men has not been unequivocally established. In fact, minimal androgen requirements for elderly men remain poorly defined and are likely to vary between individuals. Consequently, borderline androgen deficiency cannot be reliably diagnosed in the elderly, and strict differentiation between "substitutive" and "pharmacological" androgen administration is not possible. To date, only a few hundred elderly men have received androgen therapy in the setting of a randomized, controlled study, and many of these men were not androgen deficient. Most consistent effects of treatment have been on body composition, but to date there is no evidence-based documentation of clinical benefits of androgen administration to elderly men with normal or moderately low serum testosterone in terms of diminished morbidity or of improved survival or quality of life. Until the long-term risk-benefit ratio for androgen administration to elderly is established in adequately powered trials of longer duration, androgen administration to elderly men should be reserved for the minority of elderly men who have both clear clinical symptoms of hypogonadism and frankly low serum testosterone levels.

Advances in male hormone substitution therapy

Increased awareness of the clinical diagnosis of male hypogonadism has resulted in the wider use of androgen substitution therapy. Clinical signs and symptoms together with a low serum testosterone level confirm the diagnosis of male hypogonadism. Androgen replacement results in improved sexual function, mood, muscle mass and bone density in most hypogonadal men. Such benefits must be assessed against potential risks. In older men, the potential risks of androgen treatment of hypogonadism are not known. Many delivery systems for androgen substitution are now available; the preparation chosen depends on the choice of the patient and his physician. Selective androgen receptor modulators offer tissue selective biological effects and the possibility of attaining maximum efficacy and minimum adverse effects.

Treatment with oxandrolone and the durability of effects in older men

We investigated the effects of the anabolic androgen, oxandrolone, on lean body mass (LBM), muscle size, fat, and maximum voluntary muscle strength, and we determined the durability of effects after treatment was stopped. Thirty-two healthy 60- to 87-yr-old men were randomized to receive 20 mg oxandrolone/day (n = 20) or placebo (n = 12) for 12 wk. Body composition [dual-energy X-ray absorptiometry (DEXA), magnetic resonance imaging, and (2)H(2)O dilution] and muscle strength [1 repetition maximum (1 RM)] were evaluated at baseline and after 12 wk of treatment; body composition (DEXA) and 1-RM strength were then assessed 12 wk after treatment was discontinued (week 24). At week 12, oxandrolone increased LBM by 3.0 +/- 1.5 kg (P < 0.001), total body water by 2.9 +/- 3.7 kg (P = 0.002), and proximal thigh muscle area by 12.4 +/- 8.4 cm(2) (P < 0.001); these increases were greater (P < 0.003) than in the placebo group. Oxandrolone increased 1-RM strength for leg press by 6.7 +/- 6.4% (P < 0.001), leg flexion by 7.0 +/- 7.8% (P < 0.001), chest press by 9.3 +/- 6.7% (P < 0.001), and latissimus pull-down exercises by 5.1 +/- 9.1% (P = 0.02); these increases were greater than placebo. Oxandrolone reduced total (-1.9 +/- 1.0 kg) and trunk fat (-1.3 +/- 0.6 kg; P < 0.001), and these decreases were greater (P < 0.001) than placebo. Twelve weeks after oxandrolone was discontinued (week 24), the increments in LBM and muscle strength were no longer different from baseline (P > 0.15). However, the decreases in total and trunk fat were sustained (-1.5 +/- 1.8, P = 0.001 and -1.0 +/- 1.1 kg, P < 0.001, respectively). Thus oxandrolone induced short-term improvements in LBM, muscle area, and strength, while reducing whole body and trunk adiposity. Anabolic improvements were lost 12 wk after discontinuing oxandrolone, whereas improvements in fat mass were largely sustained.

An integrative review on current evidence of testosterone replacement therapy for the andropause

OBJECTIVES

This paper examines the evidence supporting testosterone replacement in aging males. Confounding factors contributing to low testosterone levels and challenges to diagnosis of the andropause will also be considered.

METHODS

A thorough review using an integrative approach citing published literature and the ongoing work of the authors. A search was performed using National Library of Medicine PubMed. Electronic and print journals available at the Texas Medical Center library were also considered.

RESULTS

Information based on collective trials in older men has added to evidence for benefits and side effects of testosterone replacement inferred from studies in younger hypogonadal patients and animal models. In general, most investigators agree with short-term safety but long-term safety is unknown. Testosterone therapy in aging males improves body composition, certain domains of brain function and may also decrease cardiovascular risk in biological models. Measurable clinical effects are less apparent. Potential risks include erythrocytosis, edema, gynecomastia, and prostate stimulation. The possibility of increased risk of clinically significant prostate cancer and cardiovascular disease has been considered.

CONCLUSION

The search continues for an ideal replacement androgen and larger long-term studies are needed. At this time, androgen replacement is on a case-by-case basis and prostate cancer screening should be completed prior to instituting therapy. Routine androgen replacement therapy for aging males will have significant economic implications, and is not currently recommended.

Effects of an oral androgen on muscle and metabolism in older, community-dwelling men

To determine whether oxymetholone increases lean body mass (LBM) and skeletal muscle strength in older persons, 31 men 65-80 yr of age were randomized to placebo (group 1) or 50 mg (group 2) or 100 mg (group 3) daily for 12 wk. For the three groups, total LBM increased by 0.0 +/- 0.6, 3.3 +/- 1.2 (P < 0.001), and 4.2 +/- 2.4 kg (P < 0.001), respectively. Trunk fat decreased by 0.2 +/- 0.4, 1.7 +/- 1.0 (P = 0.018), and 2.2 +/- 0.9 kg (P = 0.005) in groups 1, 2, and 3, respectively. Relative increases in 1-repetition maximum (1-RM) strength for biaxial chest press of 8.2 +/- 9.2 and 13.9 +/- 8.1% in the two active treatment groups were significantly different from the change (-0.8 +/- 4.3%) for the placebo group (P < 0.03). For lat pull-down, 1-RM changed by -0.6 +/- 8.3, 8.8 +/- 15.1, and 18.4 +/- 21.0% for the groups, respectively (1-way ANOVA, P = 0.019). The pattern of changes among the groups for LBM and upper-body strength suggested that changes might be related to dose. Alanine aminotransferase increased by 72 +/- 67 U/l in group 3 (P < 0.001), and HDL-cholesterol decreased by -19 +/- 9 and -23 +/- 18 mg/dl in groups 2 and 3, respectively (P = 0.04 and P = 0.008). Thus oxymetholone improved LBM and maximal voluntary muscle strength and decreased fat mass in older men.

Effects of transdermal testosterone on lipids and vascular reactivity in older men with low bioavailable testosterone levels

BACKGROUND

Sex hormones are known to affect cholesterol levels and vascular tone in women. The effects of testosterone on cholesterol and vascular tone in men are less well understood. Low testosterone levels have been associated with higher cholesterol levels in epidemiologic studies, but testosterone replacement has resulted in variable changes in cholesterol levels. Similarly, clinical studies suggest that testosterone may be vasodilatory, but few studies have directly evaluated the effects of testosterone on vascular tone.

METHODS

Sixty-seven men (mean age 76 +/- 4 years, range 65-87) with bioavailable testosterone levels below 4.44 nmol/l (lower limit for adult normal range) were randomized to receive transdermal testosterone (2-2.5 mg patches/d) or placebo patches for 1 year. Twenty-three men (34%) withdrew from the study; 44 men completed the trial.

RESULTS

While total cholesterol, triglyceride, and low-density lipoprotein cholesterol levels did not significantly change during the year of therapy, high-density lipoprotein (HDL) levels (p =.004) and, specifically, HDL(2) subfraction (p =.02) decreased in men receiving testosterone supplementation. Vascular tone was measured by brachial artery reactivity in 36 men. Endothelium-dependent brachial artery reactivity did not change from baseline measurements in men receiving transdermal testosterone (0.3 +/- 6.7% to 1.6 +/- 4.6%; p =.58) or in the placebo group (3.2 +/- 5.5% to 0.7 +/- 5.5%; p =.23).

CONCLUSIONS

Transdermal testosterone decreased HDL(2) cholesterol but did not affect vascular reactivity in men older than 65 years selected for low testosterone levels. No study to date has addressed the direct relationship between testosterone replacement and cardiovascular events.

The effect of aromatase inhibition on sex steroids, gonadotropins, and markers of bone turnover in older men

There is evidence that estrogen decreases bone turnover in men as well as women. We therefore hypothesized that older men would show increased bone resorption in response to inhibition of the aromatase enzyme, which converts androgens to estrogen. Fifteen eugonadal men over 65 yr were treated for 9 weeks with 2.0 mg/day of anastrozole, an aromatase inhibitor. After 9 weeks of treatment, there were significant decreases in estradiol, estrone, and sex hormone-binding globulin levels by 29%, 73%, and 16%, respectively, and total testosterone increased significantly by 56%. Despite the limited decrease of estrogen and the increase in testosterone, C-telopeptide of type 1 collagen showed a progressive significant increase of 11%, 24%, and 33% (P for trend = 0.033) above baseline at 3, 6, and 9 weeks, respectively. N-telopeptide of type 1 collagen values were highly correlated with C-telopeptide of type 1 collagen, but the change in N-telopeptide of type 1 collagen was not statistically significant. Bone-specific alkaline phosphatase and N-terminal type I procollagen peptides showed significant decreases of 8% and 11% of baseline at 9 weeks. Osteocalcin decreased significantly by 30% at 18 weeks. We conclude that aromatase inhibition can reduce estrogen levels in older men, but this effect is limited, perhaps because of feedback stimulation of testosterone production, and that endogenous estrogen derived from aromatization of testosterone plays a role in bone metabolism of older men by limiting the rate of bone resorption.

Effects of transdermal testosterone on bone and muscle in older men with low bioavailable testosterone levels

BACKGROUND

A large proportion of men over 65 years of age have bioavailable testosterone levels below the reference range of young adult men. The impact of this on musculoskeletal health and the potential for improvement in function in this group with testosterone supplementation require investigation.

METHODS

Sixty-seven men (mean age 76 +/- 4 years, range 65--87) with bioavailable testosterone levels below 4.44 nmol/l (lower limit for adult normal range) were randomized to receive transdermal testosterone (two 2.5-mg patches per day) or placebo patches for 1 year. All men received 500 mg supplemental calcium and 400 IU vitamin D. Outcome measures included sex hormones (testosterone, bioavailable testosterone, sex-hormone binding globulin [SHBG], estradiol, and estrone), bone mineral density (BMD; femoral neck, Ward's triangle, trochanter, lumbar spine, and total body), bone turnover markers, lower extremity muscle strength, percent body fat, lean body mass, hemoglobin, hematocrit, prostate symptoms, and prostate specific antigen (PSA) levels.

RESULTS

Twenty-three men (34%) withdrew from the study; 44 men completed the trial. In these men, bioavailable testosterone levels increased from 3.2 +/- 1.2 nmol/l (SD) to 5.6 +/- 3.5 nmol/l (p <.002) at 12 months in the testosterone group, whereas no change occurred in the control group. Although there was no change in estradiol levels in either group, estrone levels increased in the testosterone group (103 +/- 26 pmol/l to 117 +/- 33 pmol/l; p <.017). The testosterone group had a 0.3% gain in femoral neck BMD, whereas the control group lost 1.6% over 12 months (p =.015). No significant changes were seen in markers of bone turnover in either group. Improvements in muscle strength were seen in both groups at 12 months compared with baseline scores. Strength increased 38% (p =.017) in the testosterone group and 27% in the control group (p =.06), with no statistical difference between the groups. In the testosterone group, body fat decreased from 26.3 +/- 5.8% to 24.6 +/- 6.5% (p =.001), and lean body mass increased from 56.2 +/- 5.3 kg to 57.2 +/- 5.1 kg (p =.001), whereas body mass did not change. Men receiving testosterone had an increase in PSA from 2.0 +/- 1.4 microg/l to 2.6 +/- 1.8 microg/l (p =.04), whereas men receiving placebo had an increase in PSA from 1.9 +/- 1.0 microg/l to 2.2 +/- 1.5 microg/l (p =.09). No significant differences between groups were seen in hemoglobin, hematocrit, symptoms or signs of benign prostate hyperplasia, or PSA levels.

CONCLUSIONS

Transdermal testosterone (5 mg/d) prevented bone loss at the femoral neck, decreased body fat, and increased lean body mass in a group of healthy men over age 65 with low bioavailable testosterone levels. In addition, both testosterone and placebo groups demonstrated gains in lower extremity muscle strength, possibly due to the beneficial effects of vitamin D. Testosterone did result in a modest increase in PSA levels but resulted in no change in signs or symptoms of prostate hyperplasia.