Cognitive response to testosterone replacement added to intensive lifestyle intervention in older men with obesity and hypogonadism: prespecified secondary analyses of a randomized clinical trial

Beneficial effects of exercise, testosterone, vitamin D, calcium and protein in older men-A randomized clinical trial

BACKGROUND

Due to increasing older populations worldwide, injuries, disabilities and deaths caused by falls among the elderly represent a growing human and societal problem. We aimed to improve health among men of at least 70 years of age with low-normal to low testosterone and mobility problems by using testosterone undecanoate (TU) injections, progressive strength training, and oral supplements of vitamin D, calcium and protein.

METHODS

This was a single-centre, randomized, placebo-controlled, double-blind trial with 148 older men with a median age of 77 (73-81) years, testosterone levels at median 8 (5-9) nmol/L (full range from 1.1 to 12.9 nmol/L) and mobility problems, recruited at University Hospital of Copenhagen, Herlev Hospital, Denmark. Participants were randomized into four arms for 20 weeks: (1) TU therapy (n = 37); (2) progressive resistance training with supplements of calcium, vitamin D and protein (n = 36); (3) both interventions combined (n = 36); or (4) no intervention (n = 39). The main outcome measure was the 30-s chair stand test, due to test performance correlating with the risk of serious fall injuries and lower extremity muscle strength. Outcome measurements were performed at baseline and after 20 weeks.

RESULTS

After the intervention, the combination group receiving progressive resistance training, TU and supplements achieved a median score of 13 (11-15) compared to the control group at 10 (0-14) in the 30-s chair stand test (P = 0.003). This median improvement of 3.0 was clinically important. Compared to the control group, participants in the combination group also increased quality of life (P < 0.05) and reduced both tiredness (P < 0.05) and leg fat (P < 0.05) and had higher variability in the RR interval (P < 0.01). The group receiving TU reduced gynoid and leg fat compared to the control group (both P < 0.05). Blood tests improved for several variables, especially in the combination group. There was no statistically significant increase in adverse effects from either the supplements or training.

CONCLUSIONS

In men ≥70 years old with low-normal to low testosterone and mobility problems, supplements of testosterone, calcium, vitamin D and protein combined with progressive resistance training improved 30-s chair stand test performance, muscle strength and quality of life. Both tiredness and leg fat were reduced, and RR interval variability was increased. Significant adverse effects were not observed.

Correlation between obesity and Alzheimers disease and the mechanisms

Alzheimer's disease (AD) is a progressive central neurodegenerative disorder with an insidious onset. With global aging, the incidence and mortality of AD have been steadily increasing, yet effective treatments remain elusive. Obesity, characterized by excessive or abnormal fat accumulation, is a complex metabolic disorder and a confirmed risk factor for numerous diseases. Both obesity and AD have become major public health concerns, posing significant threats to human health and economic development. Studies have revealed a strong correlation between obesity and AD, with multiple contributing factors, including metabolic abnormalities of endocrine factors, inflammatory responses, and genetic interactions. Exploring the correlation and mechanisms between obesity and AD provides important insights and new strategies for the prevention and treatment of AD.

Androgen effects on mesoprefrontal dopamine systems in the adult male brain

Epidemiological data show that males are more often and/or more severely affected by symptoms of prefrontal cortical dysfunction in schizophrenia, Parkinson's disease and other disorders in which dopamine circuits associated with the prefrontal cortex are dysregulated. This review focuses on research showing that these dopamine circuits are powerfully regulated by androgens. It begins with a brief overview of the sex differences that distinguish prefrontal function in health and prefrontal dysfunction or decline in aging and/or neuropsychiatric disease. This review article then spotlights data from human subjects and animal models that specifically identify androgens as potent modulators of prefrontal cortical operations and of closely related, functionally critical measures of prefrontal dopamine level or tone. Candidate mechanisms by which androgens dynamically control mesoprefrontal dopamine systems and impact prefrontal states of hypo- and hyper-dopaminergia in aging and disease are then considered. This is followed by discussion of a working model that identifies a key locus for androgen modulation of mesoprefrontal dopamine systems as residing within the prefrontal cortex itself. The last sections of this review critically consider the ways in which the organization and regulation of mesoprefrontal dopamine circuits differ in the adult male and female brain, and highlights gaps where more research is needed.

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.

Sex and gender correlates of sexually polymorphic cognition

BACKGROUND

Sexually polymorphic cognition (SPC) results from the interaction between biological (birth-assigned sex (BAS), sex hormones) and socio-cultural (gender identity, gender roles, sexual orientation) factors. The literature remains quite mixed regarding the magnitude of the effects of these variables. This project used a battery of classic cognitive tests designed to assess the influence of sex hormones on cognitive performance. At the same time, we aimed to assess the inter-related and respective effects that BAS, sex hormones, and gender-related factors have on SPC.

METHODS

We recruited 222 adults who completed eight cognitive tasks that assessed a variety of cognitive domains during a 150-min session. Subgroups were separated based on gender identity and sexual orientation and recruited as follows: cisgender heterosexual men (n = 46), cisgender non-heterosexual men (n = 36), cisgender heterosexual women (n = 36), cisgender non-heterosexual women (n = 38), gender diverse (n = 66). Saliva samples were collected before, during, and after the test to assess testosterone, estradiol, progesterone, cortisol, and dehydroepiandrosterone. Psychosocial variables were derived from self-report questionnaires.

RESULTS

Cognitive performance reflects sex and gender differences that are partially consistent with the literature. Interestingly, biological factors seem to better explain differences in male-typed cognitive tasks (i.e., spatial), while psychosocial factors seem to better explain differences in female-typed cognitive tasks (i.e., verbal).

CONCLUSION

Our results establish a better comprehension of SPC over and above the effects of BAS as a binary variable. We highlight the importance of treating sex as a biological factor and gender as a socio-cultural factor together since they collectively influence SPC.

Testosterone replacement therapy: clinical considerations

INTRODUCTION

As an increasingly popular therapeutic option, testosterone replacement therapy (TRT) has gained significant notoriety for its health benefits in indicated populations, such as those suffering from hypogonadism.

AREAS COVERED

Benefits such as improved libido, muscle mass, cognition, and quality of life have led to widened public interest in testosterone as a health supplement. No therapy exists without side effects; testosterone replacement therapy has been associated with side effects such as an increased risk of polycythemia, benign prostate hypertrophy (BPH), prostate cancer, gynecomastia, testicular atrophy, and infertility. Testosterone replacement therapy is often accompanied by several prophylactic co-therapies aimed at reducing the prevalence of these side effects. Literature searches for sections on the clinical benefits and risks associated with TRT were performed to include clinical trials, meta-analyses, and systematic reviews from the last 10 years.

EXPERT OPINION

Data from clinical studies over the last decade suggest that the benefits of this therapy outweigh the risks and result in overall increased quality of life and remission of symptoms related to hypogonadism. With this in mind, the authors of this review suggest that carefully designed clinical trials are warranted for the investigation of TRT in symptomatic age-related hypogonadism.

Treating Hypopituitarism in the Over 65s: Review of Clinical Studies

The current increase of life expectancy is associated with the presence of endocrine diseases in the elderly. The management of hypopituitarism in this group of patients is a challenging task. A correct diagnosis, which represents an essential requisite for an appropriate medical treatment, can be difficult because of the physiological changes occurring in pituitary function with aging, which may lead to challenges in the interpretation of laboratory results. Furthermore, the treatment requires several careful considerations: the need to restore the hormonal physiology with replacement therapies must be balanced with the need to avoid the risks of the over-replacement, especially in the presence of concomitant cardiovascular and metabolic disease. Interactions with other drugs able to modify the absorption and/or the metabolism of hormonal replacement therapies should be considered, in particular for the treatment of hypoadrenalism and hypothyroidism. The most important challenges stem from the lack of specific studies focused on the management of hypopituitarism in older people.

Weight strategy in older adults with obesity: calorie restriction or not?

PURPOSE OF REVIEW

Along with the marked increase in the population of older adults with obesity is the need for effective strategies to treat aging- and obesity-related complications. This review highlights recent progress in obesity management in older adults.

RECENT FINDINGS

Although calorie restriction is needed to significantly reduce fat mass, an exercise protocol is crucial to ameliorate functional outcomes. The addition of a resistance exercise protocol improves the response of muscle protein synthesis to anabolic stimuli, preventing the calorie restriction-induced reduction in muscle and bone mass. The addition of an aerobic exercise protocol improves cardiorespiratory fitness and cognitive function. However, the addition of both aerobic and resistance exercise protocols to calorie restriction provides the greatest improvements in myocellular quality, frailty, and cardiometabolic and cognitive outcomes, translating into the greatest improvement in quality of life. Such comprehensive lifestyle intervention effectively improves glucometabolic control and age-relevant outcomes in older adults with diabetes. When combined with testosterone therapy, such lifestyle intervention also preserves muscle and bone mass in older, men with obesity and hypogonadism.

SUMMARY

We conclude that calorie restriction among older adults with obesity should be prescribed in combination with both aerobic and resistance exercise to maximize benefits on overall health.

Testosterone, cognitive decline and dementia in ageing men

As men grow older, circulating testosterone concentrations decline, while prevalence of cognitive impairment and dementia increase. Epidemiological studies of middle-aged and older men have demonstrated associations of lower testosterone concentrations with higher prevalence and incidence of cognitive decline and dementia, including Alzheimer's disease. In observational studies, men with prostate cancer treated by androgen deprivation therapy had a higher risk of dementia. Small intervention studies of testosterone using different measures of cognitive function have provided inconsistent results, with some suggesting improvement. A randomised placebo-controlled trial of one year's testosterone treatment conducted in 788 men aged ≥ 65 years, baseline testosterone < 9.54 nmol/L, showed an improvement in sexual function, but no improvement in cognitive function. There is a known association between diabetes and dementia risk. A randomised placebo-controlled trial of two year's testosterone treatment in 1,007 men aged 50-74 years, waist circumference ≥ 95 cm, baseline testosterone ≤ 14 nmol/L, showed an effect of testosterone in reducing type 2 diabetes risk. There were no cognitive endpoints in that trial. Additional research is warranted but at this stage lower testosterone concentrations in ageing men should be regarded as a biomarker rather than a proven therapeutic target for risk reduction of cognitive decline and dementia, including Alzheimer's disease.