Insulin resistance in transgender individuals correlates with android fat mass

Body composition and risk for sarcopenia in transgender women

OBJECTIVES

Body composition and strength of cisgender (cis) individuals are well established. However, those for transgender women (trans women) undergoing gender-affirming hormone therapy remain unclear. This study aimed to detect possible body composition and strength variations related to sarcopenia.

METHODS

This was a cross-sectional comparative study of 37 trans women, 34 cis men, and 34 cis women. Body composition was measured in all individuals by bioelectrical impedance analysis; prehensile strength by dynamometry was studied in trans women.

RESULTS

In this study, trans women had higher body mass index values than cis individuals (P < 0.01). Fat mass was 41% higher for trans women than cis men. Muscle mass (MM) was lower in trans women than cis men (-10%), and higher than cis women (24%). Bone mass was lower in trans women than cis men and higher in cis women (P < 0.01). Trans women's prehensile strengths were 25.26 kg for the right hand and 24.8 kg for the left. Appendicular skeletal muscle mass was 23.63 kg, and appendicular skeletal muscle mass index was 8.14 kg.

CONCLUSION

Trans women undergoing gender-affirming hormone therapy show a tendency to adapt body compartments to those of cis women with increased fat mass and reduced muscle mass. Prehensile strength in trans women was close to the cutoff points for sarcopenia risk. Nutrition, physical activity, strength, and body composition are important to avoid the possible risk for sarcopenia. More studies along these lines are necessary, especially in older adults.

Insulin sensitivity, body composition and bone mineral density after testosterone treatment in transgender youth with and without prior GnRH agonist therapy

Background

1.8% of youth identify as transgender; a growing proportion are transgender male (female sex, male gender identity). Many receive gonadotropin releasing hormone agonist (GnRHa) therapy to suppress endogenous puberty and/or will start testosterone to induce secondary sex characteristics that align with gender identity.

Objectives

To determine the effects of 12 months of testosterone on cardiometabolic health among transgender youth, including insulin sensitivity, body composition, and bone mineral density and whether changes in outcomes differ based on prior GnRHa treatment.

Methods

Participants (n = 19, baseline age 15.0 ± 1.0 years) were examined prior to and 12 months after testosterone therapy in a longitudinal observational study. Fasted morning blood draw, a 2-hour 75-gram oral glucose tolerance test, body composition and bone mineral density (dual-energy X-ray absorptiometry) were assessed at baseline and 12 months. Insulin sensitivity was estimated by HOMA-IR and Matsuda index. Changes were compared with mixed linear regression models evaluating time (baseline, 12 months), group (GnRHa treatment yes/no), and their interaction.

Results

In the entire cohort, fasted insulin decreased (median [25,75 %ile]: -3 [-5, 0] mIU/L, p = 0.044) and 2-hour glucose increased (mean ± standard deviation): +18.5 ± 28.9 mg/dL, p = 0.013 from baseline after 12 months of testosterone therapy. There were no significant changes in HOMA-IR (p = 0.062) or Matsuda index (p = 0.096), nor by GnRHa status. Absolute (+6.2 [4.7, 7.5] kg, p = 0.016) and percent fat-free mass increased (+7.3 [5.4, 9.1] %, p = 0.003) and percent fat mass declined (-7.4 [-9.3, 5.3]%, p = 0.005) for the entire cohort. There were time*group interactions for absolute (p = 0.0007) and percent fat-free mass (p = 0.033). There were time*group interactions for bone mineral content (p = 0.006).

Conclusions

Twelve months of testosterone in transgender adolescents resulted in changes in body composition and bone mineral density, with baseline differences between the +/-GnRHa group and convergence after 12 months. There were no changes in insulin sensitivity over time or between groups.

Gender-affirming hormone therapy and cardiovascular health in transgender adults

A growing number of people identify as transgender and gender non-binary in the USA and worldwide. Concomitantly, an increasing number of patients are receiving gender-affirming hormone therapy (GAHT) to achieve gender congruence. GAHT has far-ranging effects on clinical and subclinical markers of cardiovascular risk. Transgender patients also appear to be at higher risk for cardiovascular diseases compared to their cisgender peers and the impact of gender-affirming therapy on cardiovascular health is unclear. Studies on the effect of GAHT on cardiovascular outcomes are confounded by differences in GAHT regimens and methodological challenges in a diverse and historically hard-to-reach population. Current cardiovascular guidelines do not incorporate gender identity and hormone status into risk stratification and clinical decision-making. In this review, we provide an overview on the cardiometabolic impact and clinical considerations of GAHT for cardiovascular risk in transgender patients.

Transgender Women Exhibit a Distinct Stress Echocardiography Profile Compared With Age-Matched Cisgender Counterparts: The Mayo Clinic Women's Heart Clinic Experience

BACKGROUND

Stress echocardiographic (SE) testing is an important modality in cardiovascular risk stratification and obstructive coronary artery disease assessment. Binary sex-based parameters are classically used for the interpretation of these studies, even among transgender women (TGW). Coronary artery disease is a leading cause of morbidity and mortality in this population. Yet, it remains unclear whether TGW exhibit a distinct stress testing profile from their cisgender counterparts.

METHODS

Using a matched case-control study design, the authors compared the echocardiographic stress testing profiles of TGW (n = 43) with those of matched cisgender men (CGM; n = 84) and cisgender women (CGW; n = 86) at a single center. Relevant data, including demographics, comorbidities, and cardiac testing data, were manually extracted from the patients' charts.

RESULTS

The prevalence of hypertension and dyslipidemia was similar between TGW and CGW and lower than that of CGM (P = .003 and P = .009, respectively). The majority of comorbidities and laboratory values were similar. On average, TGW had higher heart rates than CGM (P = .002) and had lower blood pressures than CGM and CGW (P < .05). TGW's double product and metabolic equivalents were similar to those among CGW and lower than those of CGM (P = .016 and P = .018, respectively). On echocardiography, left ventricular end-diastolic and end-systolic diameters among TGW were similar to those of CGW but lower than those of CGM (P = .023 and P = .018, respectively). Measures of systolic and diastolic function, except for exercise mitral valve E/e' ratio, which was lower in TGW than CGW (P = .029), were largely similar among the three groups. There was no difference in the wall motion score index, and therefore, no difference in the percentage of positive SE test results.

CONCLUSIONS

This study shows, for the first time, that TGW have a SE profile that is distinct from that of their cisgender counterparts. Larger, multicenter, prospective studies are warranted to further characterize the SE profile of TGW.

The International Olympic Committee framework on fairness, inclusion and nondiscrimination on the basis of gender identity and sex variations does not protect fairness for female athletes

The International Olympic Committee (IOC) recently published a framework on fairness, inclusion, and nondiscrimination on the basis of gender identity and sex variations. Although we appreciate the IOC's recognition of the role of sports science and medicine in policy development, we disagree with the assertion that the IOC framework is consistent with existing scientific and medical evidence and question its recommendations for implementation. Testosterone exposure during male development results in physical differences between male and female bodies; this process underpins male athletic advantage in muscle mass, strength and power, and endurance and aerobic capacity. The IOC's "no presumption of advantage" principle disregards this reality. Studies show that transgender women (male-born individuals who identify as women) with suppressed testosterone retain muscle mass, strength, and other physical advantages compared to females; male performance advantage cannot be eliminated with testosterone suppression. The IOC's concept of "meaningful competition" is flawed because fairness of category does not hinge on closely matched performances. The female category ensures fair competition for female athletes by excluding male advantages. Case-by-case testing for transgender women may lead to stigmatization and cannot be robustly managed in practice. We argue that eligibility criteria for female competition must consider male development rather than relying on current testosterone levels. Female athletes should be recognized as the key stakeholders in the consultation and decision-making processes. We urge the IOC to reevaluate the recommendations of their Framework to include a comprehensive understanding of the biological advantages of male development to ensure fairness and safety in female sports.

The Impact of Gender-Affirming Hormone Therapy on Physical Performance

CONTEXT

The inclusion of transgender people in elite sport has been a topic of debate. This narrative review examines the impact of gender-affirming hormone therapy (GAHT) on physical performance, muscle strength, and markers of endurance.

EVIDENCE ACQUISITION

MEDLINE and Embase were searched using terms to define the population (transgender), intervention (GAHT), and physical performance outcomes.

EVIDENCE SYNTHESIS

Existing literature comprises cross-sectional or small uncontrolled longitudinal studies of short duration. In nonathletic trans men starting testosterone therapy, within 1 year, muscle mass and strength increased and, by 3 years, physical performance (push-ups, sit-ups, run time) improved to the level of cisgender men. In nonathletic trans women, feminizing hormone therapy increased fat mass by approximately 30% and decreased muscle mass by approximately 5% after 12 months, and steadily declined beyond 3 years. While absolute lean mass remains higher in trans women, relative percentage lean mass and fat mass (and muscle strength corrected for lean mass), hemoglobin, and VO2 peak corrected for weight was no different to cisgender women. After 2 years of GAHT, no advantage was observed for physical performance measured by running time or in trans women. By 4 years, there was no advantage in sit-ups. While push-up performance declined in trans women, a statistical advantage remained relative to cisgender women.

CONCLUSION

Limited evidence suggests that physical performance of nonathletic trans people who have undergone GAHT for at least 2 years approaches that of cisgender controls. Further controlled longitudinal research is needed in trans athletes and nonathletes.

Gender-affirming hormone therapy decreases d-dimer but worsens insulin sensitivity in transgender women

OBJECTIVES

Gender-affirming hormonal therapies (GAHT) and HIV increase cardiovascular risk for transgender women (TW), yet there is a paucity of data quantifying cardiometabolic changes following GAHT initiation, particularly among TW with HIV.

METHODS

The Féminas study enrolled TW from October 2016 to March 2017 in Lima, Peru. Participants reported sexual activity that was high risk for HIV acquisition or transmission. All were tested for HIV/ sexually transmitted infection and were given access to GAHT (oestradiol valerate and spironolactone), HIV pre-exposure prophylaxis (PrEP) or antiretroviral therapy (ART) for 12 months. Biomarker measurement was done on stored serum, whereas fasting glucose and lipids were measured in real time.

RESULTS

In all, 170 TW (32 with HIV, 138 without HIV) had median age 27 years and 70% prior GAHT use. At baseline, PCSK9, sCD14, sCD163, IL-6, sTNFRI/II, CRP and EN-RAGE levels were significantly higher in TW with HIV than in TW without HIV. High-density lipoprotein and total cholesterol were lower and insulin and glucose parameters were similar. All TW with HIV started ART, but only five achieved virological suppression at any time. No TW without HIV initiated PrEP. Over 6 months, all participants initiated GAHT and had worsening insulin, glucose and HOMA-IR. Large d-dimer decreases also occurred. Similar changes occurred in TW with and without HIV.

CONCLUSIONS

In this unique cohort of TW, GAHT decreased d-dimer but worsened insulin sensitivity. Because PrEP uptake and ART adherence were very low, observed effects are primarily attributed to GAHT use. Further study is needed to better understand cardiometabolic changes in TW by HIV serostatus.

The molecular consequences of androgen activity in the human breast

Estrogen and progesterone have been extensively studied in the mammary gland, but the molecular effects of androgen remain largely unexplored. Transgender men are recorded as female at birth but identify as male and may undergo gender-affirming androgen therapy to align their physical characteristics and gender identity. Here we perform single-cell-resolution transcriptome, chromatin, and spatial profiling of breast tissues from transgender men following androgen therapy. We find canonical androgen receptor gene targets are upregulated in cells expressing the androgen receptor and that paracrine signaling likely drives sex-relevant androgenic effects in other cell types. We also observe involution of the epithelium and a spatial reconfiguration of immune, fibroblast, and vascular cells, and identify a gene regulatory network associated with androgen-induced fat loss. This work elucidates the molecular consequences of androgen activity in the human breast at single-cell resolution.

The role of oestrogen in determining sexual dimorphism in energy balance

Energy balance is determined by caloric intake and the rate at which energy is expended, with the latter comprising resting energy expenditure, physical activity and adaptive thermogenesis. The regulation of both energy intake and expenditure exhibits clear sexual dimorphism, with young women being relatively protected against weight gain and the development of cardiometabolic diseases. Preclinical studies have indicated that females are more sensitive to the satiety effects of leptin and insulin compared to males. Furthermore, females have greater thermogenic activity than males, whereas resting energy expenditure is generally higher in males than females. In addition to this, in post-menopausal women, the decline in sex steroid concentration, particularly in oestrogen, is associated with a shift in the distribution of adipose tissue and overall increased propensity to gain weight. Oestrogens are known to regulate energy balance and weight homeostasis via effects on both food intake and energy expenditure. Indeed, 17β-oestradiol treatment increases melanocortin signalling in the hypothalamus to cause satiety. Furthermore, oestrogenic action at the ventromedial hypothalamus has been linked with increased energy expenditure in female mice. We propose that oestrogen action on energy balance is multi-faceted and is fundamental to determining sexual dimorphism in weight control. Furthermore, evidence suggests that the decline in oestrogen levels leads to increased risk of weight gain and development of cardiometabolic disease in women across the menopausal transition.

Estrogen May Enhance Toll-Like Receptor 4-Induced Inflammatory Pathways in People With HIV: Implications for Transgender Women on Hormone Therapy

Background

Transgender women (TW) are at increased risk for both human immunodeficiency virus (HIV) and cardiovascular disease (CVD). Antiretroviral therapy-treated HIV has been associated with a two-fold increased risk of CVD, potentially due to dysregulated Toll-like receptor (TLR)-induced immune activation. Use of estrogens in feminizing hormone therapy (FHT) may enhance inflammatory responses and the risk of cardiovascular mortality in TW. Despite this, the immunomodulatory effects of estrogen use in TW with HIV have been inadequately explored.

Methods

As an in vitro model for FHT, cryopreserved PBMCs (cryoPBMCs) from HIV negative (HIV-), HIV+ ART-suppressed (HIV+SP), and HIV+ ART-unsuppressed (HIV+USP) cisgender men were cultured overnight in the presence of 17-β estradiol or 17-α ethinylestradiol with and without the TLR4 agonist LPS or the TLR8 agonist ssPolyU. Monocyte activation (CD69, HLA-DR, CD38) was assessed by flow cytometry. Cytokine levels (IL-6, TNF-α, IL-1β, and IL-10) were measured in cell culture supernatants by Legendplex. Levels of phosphorylated TLR signaling molecules (JNK, MAPK p38) were assessed by Phosflow. Plasma levels of immune activation biomarkers (LPS-binding protein, monocyte activation markers sCD14 and sCD163, and inflammatory molecules IL-6 and TNF-α receptor I) were measured by ELISA.

Results

PBMCs from people with HIV (PWH) produced greater levels of inflammatory cytokines following exposure to LPS or ssPolyU compared to levels from cells of HIV- individuals. While estrogen exposure alone induced mild changes in immune activation, LPS-induced TLR4 activation was elevated with estrogen in cisgender men (CM) with HIV, increasing monocyte activation and inflammatory cytokine production (IL-6, TNF-α). Interestingly, testosterone inhibited LPS-induced cytokine production in CM regardless of HIV status. Plasma markers of immune activation and microbial translocation (e.g., sCD14, sCD163, LPS-binding protein) were generally higher in PWH compared to HIV- CM, and these markers were positively associated with in vitro responsiveness to estrogen and LPS in CM with HIV.

Conclusions

Our in vitro data suggest that estrogen exposure may enhance innate immune activation in PWH. Further examination is needed to fully understand the complex interactions of FHT, HIV, and CVD in TW, and determine optimal FHT regimens or supplementary treatments aimed at reducing excess immune activation.

Digestive Health in Sexual and Gender Minority Populations

It has been over 50 years since the Stonewall Inn Riots in June 1969, a seminal event for the lesbian, gay, bisexual, transgender, queer, intersex, and other sexual and gender-diverse minorities (LGBTQI+, or lesbian, gay, bisexual, transgender, queer, intersex, and everyone else) rights movement. However, sexual and gender minority (SGM) individuals still face discrimination and harassment due to their sexual orientation or gender identity. As such, the National Institute on Minority Health and Health Disparities has identified SGM communities as a "health disparity population." Broadly, there are higher rates of sexually transmitted infections, substance use and abuse, mental health conditions, obesity and eating disorders, certain cancers (breast, cervical, and anorectal), and cardiovascular disease in SGM communities. Transgender patients, especially those of color, are more likely to be uninsured, experience discrimination, and be denied health care than cisgender patients. In addition, SGM individuals have twice the risk of lifetime exposure to emotional, physical, and sexual trauma compared with heterosexuals. It is expected all these factors would negatively affect digestive health as well. This review summarizes the effects of social determinants of health and discrimination on health care access, highlights important digestive diseases to consider in the SGM population, and offers solutions to improve and prioritize the health of these communities. We aim to draw attention to SGM-specific issues that affect gastrointestinal health and spur research that is desperately lacking.

Uncovering the effects of gender affirming hormone therapy on skeletal muscle and epigenetics: protocol for a prospective matched cohort study in transgender individuals (the GAME study)

INTRODUCTION

Gender affirming hormone therapy (GAHT) is increasingly used by transgender individuals and leads to shifts in sex hormone levels. Skeletal muscle is highly responsive to hormone activity, with limited data on the effects of GAHT on different human tissues. Here, we present the protocol for the GAME study (the effects of Gender Affirming hormone therapy on skeletal Muscle training and Epigenetics), which aims to uncover the effects of GAHT on skeletal muscle 'omic' profiles (methylomics, transcriptomics, proteomics, metabolomics) and markers of skeletal muscle health and fitness.

METHODS AND ANALYSIS

This study is a prospective age-matched cohort study in transgender adults commencing GAHT (n=80) and age-matched individuals not commencing GAHT (n=80), conducted at Austin Health and Victoria University in Victoria, Australia. Assessments will take place prior to beginning GAHT and 6 and 12 months into therapies in adults commencing GAHT. Age-matched individuals will be assessed at the same time points. Assessments will be divided over three examination days, involving (1) aerobic fitness tests, (2) muscle strength assessments and (3) collection of blood and muscle samples, as well as body composition measurements. Standardised diets, fitness watches and questionnaires will be used to control for key confounders in analyses. Primary outcomes are changes in aerobic fitness and muscle strength, as well as changes in skeletal muscle DNA methylation and gene expression profiles. Secondary outcomes include changes in skeletal muscle characteristics, proteomics, body composition and blood markers. Linear mixed models will be used to assess changes in outcomes, while accounting for repeated measures within participants and adjusting for known confounders.

ETHICS AND DISSEMINATION

The Austin Health Human Research Ethics Committee (HREC) and Victoria University HREC granted approval for this study (HREC/77146/Austin-2021). Findings from this project will be published in open-access, peer-reviewed journals and presented to scientific and public audiences.

TRIAL REGISTRATION NUMBER

ACTRN12621001415897; Pre-results.

Gender-affirming hormone therapy: An updated literature review with an eye on the future

In line with increasing numbers of transgender (trans) and gender nonbinary people requesting hormone treatment, the body of available research is expanding. More clinical research groups are presenting data, and the numbers of participants in these studies are rising. Many previous review papers have focused on all available data, as these were scarce, but a more recent literature review is timely. Hormonal regimens have changed over time, and older data may be less relevant for today's practice. In recent literature, we have found that even though mental health problems are more prevalent in trans people compared to cisgender people, less psychological difficulties occur, and life satisfaction increases with gender-affirming hormone treatment (GAHT) for those who feel this is a necessity. With GAHT, body composition and contours change towards the affirmed sex. Studies in bone health are reassuring, but special attention is needed for adolescent and adult trans women, aiming at adequate dosage of hormonal supplementation and stimulating therapy compliance. Existing epidemiological data suggest that the use of (certain) estrogens in trans women induces an increased risk of myocardial infarction and stroke, the reason that lifestyle management can be an integral part of trans health care. The observed cancer risk in trans people does not exceed the known cancer-risk differences between men and women. Now it is time to integrate the mostly reassuring data, to leave the overly cautious approach behind, to not copy the same research questions repeatedly, and to focus on longer follow-up data with larger cohorts.

Method of Calculating Renal Function Estimates Could Inappropriately Exclude Transgender Patients Receiving Gender-Affirming Hormone Therapy from Pre-Exposure Prophylaxis Eligibility

Purpose: Despite the importance of reliable renal function estimation among the growing transgender population, research describing the variability of existing equations is scarce. Study objectives were to (1) quantify the range of renal function estimates that would be observed if different gender coefficients are used in the estimating equations, (2) compare estimates of renal function (creatinine clearance [CL_CR] or estimated glomerular filtration rate [GFR]) between users and nonusers of gender-affirming therapies, and (3) quantify the proportion of subjects who would be deemed ineligible for tenofovir disoproxil fumarate/emtricitabine (TDF/FTC) for pre-exposure prophylaxis (PrEP) based on the gender coefficient used. Methods: A retrospective analysis was performed among transgender PrEP users enrolled in a multicenter observational study between June 2017 and October 2021. The primary outcome was estimated kidney function, defined using calculated CL_CR or GFR before initiating TDF/FTC for PrEP based on the three most commonly used estimating equations. Results: A total of 258 participants were evaluated. Median differences in renal function ranged from 13 to 25 mL/min based on which gender coefficient and equation was used. Regardless of the method used to compute renal function, there were significant differences between users and nonusers of gender-affirming therapy. There were 17 (6.6%) participants where at least one of the methods would potentially render them ineligible to receive TDF/FTC for PrEP. Conclusions: Renal function estimates vary considerably with different estimating equations in the transgender population and are modified by use of gender-affirming therapy. These variations could result in exclusion from drug therapies such as TDF/FTC for PrEP.

Feminizing Hormone Therapy Prescription Patterns and Cardiovascular Risk Factors in Aging Transgender Individuals in Australia

CONTEXT

The safety and efficacy of feminizing hormone therapy in aging transgender (trans) individuals is unclear. Current recommendations suggest transdermal estradiol beyond the age of 45 years, especially if cardiometabolic risk factors are present.

OBJECTIVE

To evaluate feminizing hormone therapy regimens and cardiovascular risk factors in aging trans individuals.

DESIGN

Retrospective cross-sectional analysis.

SETTING

Primary care and endocrine specialist clinic in Melbourne, Australia.

PARTICIPANTS

Trans individuals on feminizing therapy for ≥6 months.

MAIN OUTCOMES MEASURES

Feminizing hormone regimens and serum estradiol concentrations by age group: (a) ≥45 years, (b) <45 years, and prevalence of cardiometabolic risk factors in individuals ≥45 years.

RESULTS

296 individuals were stratified by age group: ≥45 years (n=55) and <45 years (n=241). There was no difference in median estradiol concentration between groups (328 nmol/L vs. 300 nmol/L, p=0.22). However, there was a higher proportion of individuals ≥45 years treated with transdermal estradiol (31% vs. 8%, p<0.00001). Of those treated with oral estradiol, the median dose was lower in the ≥45 years group (4mg vs. 6mg, p=0.01). The most prevalent cardiometabolic risk factor in the ≥45 years group was hypertension (29%), followed by current smoking (24%), obesity (20%), dyslipidaemia (16%) and diabetes (9%).

CONCLUSIONS

A greater proportion of trans individuals ≥45 years of age were treated with transdermal estradiol. Of those who received oral estradiol, the median dose was lower. This is important given the high prevalence of cardiometabolic risk factors in this age group, however cardiovascular risk management guidelines in this demographic are lacking.