Providing Care for Transgender Persons With Kidney Disease: A Narrative Review

Supporting Transgender, Nonbinary, and Gender Diverse Youth During Solid Organ Transplantation

As gender diversity becomes more understood and accepted in mainstream culture, medical systems and health care providers must learn to provide comprehensive and affirming care to gender diverse individuals. As the number of gender diverse pediatric patients continues to grow, these patients will be cared for by pediatric solid-organ transplant programs. This review summarizes the basic principles of gender-affirming care and describes how transplant teams can provide equitable and affirming care to young gender diverse patients undergoing solid organ transplant (SOT). In addition, this review uses kidney transplant as a framework to explore gender-affirming hormone therapy and gender-affirming surgery in the setting of transplant, laboratory value interpretation in gender diverse individuals, and the importance of an individualized approach in care of the gender diverse transplant recipient.

International Nephrology Masterclass in Chronic Kidney Disease: Rationale, Summary, and Future Perspectives

Chronic kidney disease (CKD) is a progressive condition that affects more than 10% of the population worldwide, accounting for more than 843 million (M) individuals. The prevalence of CKD (844 M patients) is higher than that of diabetes mellitus (422 M patients), cancer (42 M patients), and HIV (37 M patients), but people are often less aware of it. Global expert groups predict reductions in the nephrology workforce in the next decade, with a declining interest in nephrology careers. Over time, KDIGO guidelines have also focused on topics related to the prevention or management of CKD patients in real-life settings. On these premises, a new educational program with international experts in the field of nephrology took place from November 2022 until March 2023 in Milan, Italy. This multinational masterclass provided an educational platform providing unbiased education on diagnosis and treatment by sharing the most recent research data on CKD and comorbidities, therefore creating a snowball effect to increase the implementation of best practices worldwide, using examples from 'real-life' patient outcomes. This paper provides an overview of the International Nephrology Masterclass (INM) concept, summarizing the key lectures and discussions, and giving an outline of future key developments.

Influence of Race Modifiers in Estimated Glomerular Filtration Rate Calculations on Medication Dosing, Access, and Transplant Eligibility

The 2021 Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation for estimation of glomerular filtration rate (GFR) lower values for Black individuals relative to previous equations, which may change medication eligibility or trigger the need to reevaluate dosing decisions. Major drug classes such as antibiotics, antidiabetic medications, cardiovascular agents, medications for the treatment of psychiatric illness, and chemotherapy drugs all have estimated GFR thresholds for prescribing eligibility. However, the use of strict thresholds for medication eligibility should be heavily scrutinized, and individualized comprehensive approaches should be used for patients on the cusps of these thresholds.

Understanding the Role of Sex Hormones in Cardiovascular Kidney Metabolic Syndrome: Toward Personalized Therapeutic Approaches

Cardiovascular kidney metabolic (CKM) syndrome represents a complex interplay of cardiovascular disease (CVD), chronic kidney disease (CKD), and metabolic comorbidities, posing a significant public health challenge. Gender exerts a critical influence on CKM syndrome, affecting the disease severity and onset through intricate interactions involving sex hormones and key physiological pathways such as the renin-angiotensin system, oxidative stress, inflammation, vascular disease and insulin resistance. It is widely known that beyond the contribution of traditional risk factors, men and women exhibit significant differences in CKM syndrome and its components, with distinct patterns observed in premenopausal women and postmenopausal women compared to men. Despite women generally experiencing a lower incidence of CVD, their outcomes following cardiovascular events are often worse compared to men. The disparities also extend to the treatment approaches for kidney failure, with a higher prevalence of dialysis among men despite women exhibiting higher rates of CKD. The impact of endogenous sex hormones, the correlations between CKM and its components, as well as the long-term effects of treatment modalities using sex hormones, including hormone replacement therapies and gender-affirming therapies, have drawn attention to this topic. Current research on CKM syndrome is hindered by the scarcity of large-scale studies and insufficient integration of gender-specific considerations into treatment strategies. The underlying mechanisms driving the gender disparities in the pathogenesis of CKM syndrome, including the roles of estrogen, progesterone and testosterone derivatives, remain poorly understood, thus limiting their application in personalized therapeutic interventions. This review synthesizes existing knowledge to clarify the intricate relationship between sex hormones, gender disparities, and the progression of CVD within CKM syndrome. By addressing these knowledge gaps, this study aims to guide future research efforts and promote tailored approaches for effectively managing CKD syndrome.

A systematic review of psychosocial and sex-based contributors to gender disparities in the United States across the steps towards kidney transplantation

INTRODUCTION

Persistent findings suggest women and patients identified as "female" are less likely to receive a kidney transplant. Furthermore, the limited research on transplantation among transgender and gender diverse people suggests this population is susceptible to many of the same psychosocial and systemic barriers.

OBJECTIVE

This review sought to 1) highlight terminology used to elucidate gender disparities, 2) identify barriers present along the steps to transplantation, and 3) summarize contributors to gender disparities across the steps to transplantation.

METHODS

A systematic review of gender and sex disparities in the steps towards kidney transplantation was conducted in accordance with PRISMA guidelines across four social science and public health databases from 2005 to 23.

RESULTS

The search yielded 1696 initial results, 33 of which met inclusion criteria. A majority of studies followed a retrospective cohort design (n = 22, 66.7%), inconsistently used gender and sex related terminology (n = 21, 63.6%), and reported significant findings for gender and sex disparities within the steps towards transplantation (n = 28, 84.8%). Gender disparities among the earlier steps were characterized by patient-provider communication and perception of medical suitability whereas disparities in the later steps were characterized by differential outcomes based on older age, an above average BMI, and Black racial identity. Findings for transgender patients pointed to issues computing eGFR and the need for culturally tailored care.

DISCUSSION

Providers should be encouraged to critically examine the diagnostic criteria used to determine transplant eligibility and adopt practices that can be culturally tailored to meet the needs of patients.

Drug stewardship in chronic kidney disease to achieve effective and safe medication use

People living with chronic kidney disease (CKD) often experience multimorbidity and require polypharmacy. Kidney dysfunction can also alter the pharmacokinetics and pharmacodynamics of medications, which can modify their risks and benefits; the extent of these changes is not well understood for all situations or medications. The principle of drug stewardship is aimed at maximizing medication safety and effectiveness in a population of patients through a variety of processes including medication reconciliation, medication selection, dose adjustment, monitoring for effectiveness and safety, and discontinuation (deprescribing) when no longer necessary. This Review is aimed at serving as a resource for achieving optimal drug stewardship for patients with CKD. We describe special considerations for medication use during pregnancy and lactation, during acute illness and in patients with cancer, as well as guidance for the responsible use of over-the-counter drugs, herbal remedies, supplements and sick-day rules. We also highlight inequities in medication access worldwide and suggest policies to improve access to quality and essential medications for all persons with CKD. Further strategies to promote drug stewardship include patient education and engagement, the use of digital health tools, shared decision-making and collaboration within interdisciplinary teams. Throughout, we position the person with CKD at the centre of all drug stewardship efforts.

Development and evaluation of a clinical simulation-based educational innovation on sexual orientation and gender identity in emergency medicine

INTRODUCTION

Sexual orientation and gender identity (SOGI)-diverse patients are marginalized and poorly cared for in the emergency department, yet well-designed educational interventions to meet this gap are lacking. We developed, implemented, and assessed a novel multi-modal SOGI curriculum on health and cultural humility for emergency medicine physician trainees.

METHODS

We conducted a prospective, single-arm evaluation of our educational intervention. A convenience sample of emergency medicine resident physicians (n = 21) participated in the facilitated curriculum including didactic and clinical simulation components. Participants completed a pre- and post-curriculum evaluation that assessed clinical skills, preparedness, attitudinal awareness, and basic knowledge in caring for SOGI-diverse patients. The content of the module was based on a scoping literature review and national needs assessment of Canadian emergency physicians, educators, and trainees along with expert collaborator and input from patient/community partners. The curriculum included a facilitated pre-brief, didactic presentation, clinical simulation modules, and a structured de-brief. Participant clinical skills were evaluated before and after the educational intervention. Our primary outcome was change in clinical preparedness, attitudinal awareness, and basic knowledge in caring for SOGI-diverse patients pre- and post-intervention.

RESULTS

Our patient-centered, targeted emergency medicine SOGI health and cultural humility training resulted in a significant improvement in resident self-rated clinical preparedness, attitudes, and knowledge in caring for SOGI-diverse patients. This training was valued by participants.

CONCLUSION

We have designed an effective, patient-centered curriculum in health and cultural humility for SOGI-diverse patients in EM. Other programs can consider using this model and developed resources in their jurisdictions to enhance provider capacities to care for this marginalized group.

Evaluation of novel candidate filtration markers from a global metabolomic discovery for glomerular filtration rate estimation

Creatinine and cystatin-C are recommended for estimating glomerular filtration rate (eGFR) but accuracy is suboptimal. Here, using untargeted metabolomics data, we sought to identify candidate filtration markers for a new targeted assay using a novel approach based on their maximal joint association with measured GFR (mGFR) and with flexibility to consider their biological properties. We analyzed metabolites measured in seven diverse studies encompasing 2,851 participants on the Metabolon H4 platform that had Pearson correlations with log mGFR and used a stepwise approach to develop models to < -0.5 estimate mGFR with and without inclusion of creatinine that enabled selection of candidate markers. In total, 456 identified metabolites were present in all studies, and 36 had correlations with mGFR < -0.5. A total of 2,225 models were developed that included these metabolites; all with lower root mean square errors and smaller coefficients for demographic variables compared to estimates using untargeted creatinine. Seventeen metabolites were chosen, including 12 new candidate filtration markers. The selected metabolites had strong associations with mGFR and little dependence on demographic factors. Candidate metabolites were identified with maximal joint association with mGFR and minimal dependence on demographic variables across many varied clinical settings. These metabolites are excreted in urine and represent diverse metabolic pathways and tubular handling. Thus, our data can be used to select metabolites for a multi-analyte eGFR determination assay using mass spectrometry that potentially offers better accuracy and is less prone to non-GFR determinants than the current eGFR biomarkers.

Sex and Gender Differences in AKI

Sex differences in AKI continue to be identified. Generally, women are protected from AKI when compared to men. Much of the protection exhibited in women is diminished after menopause. These sex and age effects have also been noted in animal models of AKI. Gonadal hormones, as modifiers of incidence, severity, and progression of AKI, have been offered as likely contributors to this sex and age effect. In animal models of AKI, estrogen and testosterone seem to modulate susceptibility. Questions remain however regarding cellular and molecular changes that are initiated by modulation of these hormones because both estrogen and testosterone have effects across cell types that play a role in AKI. Although findings have largely been informed by studies in males, molecular pathways that are involved in the initiation and progression of AKI may be modulated by gonadal hormones. Compounding the hormone-receptor effects are developmental effects of sex chromosomal complement and epigenetic influences that may confer sex-based baseline differences in gene and protein expression, and gene dosage effects of X inactivation and escape on molecular pathways. Elucidation of sex-based protection may afford a more complete view of AKI and potential therapeutic interventions. Furthermore, the effect on susceptibility to AKI in transgender patients, who receive life-altering and essential gender-affirming hormone therapy, requires greater attention. In this review, several potential contributors to the sex differences observed in humans and animal models are discussed.

Kidney transplantation for a transgender male

The proportion of transgender people has increased over time, but few cases of transgender people undergoing kidney transplantation have been described. A 41-year-old transgender man (female-to-male) had chronic kidney disease caused by IgA nephropathy. He had received testosterone therapy and sex reassignment surgeries (chest masculinization surgery, metoidioplasty, scrotoplasty, and hysterectomy-ovariectomy) since he was 19 years due to gender incongruence. He underwent a preemptive living-donor kidney transplantation from his wife. His skeletal muscle mass was closer to that of a female than that of a male and suggested that eGFR should be calculated with the equation based on the gender assigned at birth (female) rather than the gender identity (male). Moreover, the recovery of kidney function due to successful kidney transplantation decreased serum gonadotropin levels, but normalization of his sex hormone profile was not achieved. Further accumulation of experience with kidney transplantation for transgender people is needed.

Sociodemographic Variables in Canadian Organ Donation Organizations: A Health Information Survey

Health systems must collect equity-relevant sociodemographic variables to measure and mitigate health inequities. The specific variables collected by organ donation organizations (ODOs) across Canada, variable definitions, and processes of the collection are not defined. We undertook a national health information survey of all ODOs in Canada. These results will inform the development of a standard national dataset of equity-relevant sociodemographic variables.

Methods

We conducted an electronic, self-administered cross-sectional survey of all ODOs in Canada from November 2021 to January 2022. We targeted key knowledge holders familiar with the data collection processes within each Canadian ODO known to Canadian Blood Services. Categorical item responses are presented as numbers and proportions.

Results

We achieved a 100% response rate from 10 Canadian ODOs. Most data were collected by organ donation coordinators. Only 2 of 10 ODOs reported using scripts explaining why sociodemographic data are being collected or incorporated training in cultural sensitivity for any given variable. A lack of cultural sensitivity training was endorsed by 50% of respondents as a barrier to the collection of sociodemographic variables by ODOs, whereas 40% of respondents identified a lack of training in sociodemographic variable collection as a significant barrier.

Conclusions

Few programs routinely collect sufficient data to examine health inequities with an intersectional lens. Most data collection occurs midway through the ODO interaction, creating a missed opportunity to better understand differences in social identities of patients who register their intention to donate in advance or who decline the donation. National standardization of equity-relevant data collection definitions and processes of the collection is needed.

Providing gender-affirming care to transgender and gender-diverse individuals with and at risk for HIV

Transgender and gender-diverse populations have unique medical and psychosocial needs. It is important that clinicians address these needs with a gender-affirming approach in all aspects of health care for these populations. Given the significant burden of HIV experienced by transgender people, such approaches in providing HIV care and prevention are essential both to engage this population in care and to work toward ending the HIV epidemic. This review presents a framework for practitioners caring for transgender and gender-diverse individuals to deliver affirming, respectful health care in HIV treatment and prevention settings.

Body, metabolic and renal changes following cross-sex estrogen/progestogen therapy in a rodent model simulating its use by transwomen

PURPOSE

The use of sex steroids by trans people has been of paramount importance regarding body changes during gender transition. The objective of this study was to assess the effects of an injectable steroid combination frequently used by transwomen, namely estradiol enanthate with dihydroxyprogesterone acetophenide (E2EN/DHPA), on blood pressure and metabolic outcomes using an animal model.

METHODS

Two-month-old male Wistar rats were orchiectomized or sham-operated and divided into groups: (1) Sham treated with sesame oil vehicle (SG), (2) sham treated with E2EN/DHPA (SP), (3) orchiectomized rats treated with vehicle (OG), and (4) orchiectomized rats treated with E2EN/DHPA (OP), with all groups treated every 10 days for 5 months. We evaluated systolic blood pressure (SBP), body weight (BW), abdominal circumference, nasoanal length (NAL), food and water intake (FI, WI), lipid profile (triglycerides, LDL, and HDL), serum C-reactive protein (CRP), plasma concentrations of urea (URpl) and creatinine (CRpl), 24 h urinary volume (V24 h), sodium and potassium excretion (UNa⁺, UK⁺), and proteinuria.

RESULTS

E2EN/DHPA administration reduced BW (SP 324.5 ± 31.1; OP 291.7 ± 41.3 g) and NAL (SP 24.5 ± 0.4; OP 24.6 ± 1.0 cm), without changing blood pressure, but increased URpl concentration (SP 55.0 ± 4.8; OP 42.5 ± 8.8 mg/dL) and CRpl (SP 0.47 ± 0.05; OP 0.46 ± 0.04 mg/dL), sodium (SP 3.1 ± 0.8; OP 3.3 ± 0.4 µEq/min/kg), potassium (SP 0.91 ± 0.22; OP 0.94 ± 0.22 µEq/min/kg) excretions and urinary volume (SP 15.5 ± 2.1; OP 16.4 ± 2.9 mL/24 h).

CONCLUSION

Cross-sex hormone therapy with E2EN/DHPA significantly modified body characteristics in male rats, producing a feminizing change without altering blood pressure or generating harmful metabolic parameters, but larger translational studies are still needed.

The effect of gender-affirming hormone treatment on serum creatinine in transgender and gender-diverse youth: implications for estimating GFR

BACKGROUND

Equations for estimated glomerular filtration rate (eGFR) based on serum creatinine include terms for sex/gender. For transgender and gender-diverse (TGD) youth, gender-affirming hormone (GAH) treatment may affect serum creatinine and in turn eGFR.

METHODS

TGD youth were recruited for this prospective, longitudinal, observational study prior to starting GAH treatment. Data collected as part of routine clinical care were abstracted from the medical record.

RESULTS

For participants designated male at birth (DMAB, N = 92), serum creatinine decreased within 6 months of estradiol treatment (mean ± SD 0.83 ± 0.12 mg/dL to 0.76 ± 0.12 mg/dL, p < 0.001); for participants designated female at birth (DFAB, n = 194), serum creatinine increased within 6 months of testosterone treatment (0.68 ± 0.10 mg/dL to 0.79 ± 0.11 mg/dL, p < 0.001). Participants DFAB treated with testosterone had serum creatinine similar to that of participants DMAB at baseline, whereas even after estradiol treatment, serum creatinine in participants DMAB remained higher than that of participants DFAB at baseline. Compared to reference groups drawn from the National Health and Nutritional Examination Survey, serum creatinine after 12 months of GAH was more similar when compared by gender identity than by designated sex.

CONCLUSION

GAH treatment leads to changes in serum creatinine within 6 months of treatment. Clinicians should consider a patient's hormonal exposure when estimating kidney function via eGFR and use other methods to estimate GFR if eGFR based on serum creatinine is concerning.

The Effect of Gender-Affirming Hormone Therapy on Measures of Kidney Function: A Systematic Review and Meta-Analysis

BACKGROUND AND OBJECTIVES

Gender-affirming hormone therapy modifies body composition and lean muscle mass in transgender persons. We sought to characterize the change in serum creatinine, other kidney function biomarkers, and GFR in transgender persons initiating masculinizing and feminizing gender-affirming hormone therapy.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We searched PubMed, EMBASE, the Cochrane Library, and ClinicalTrials.gov from inception to September 16, 2020 for randomized controlled trials, observational studies, and case series that evaluated the change in serum creatinine, other kidney function biomarkers, and GFR before and after the initiation of gender-affirming hormone therapy in adult transgender persons. Two reviewers independently screened and abstracted data, and disagreements were resolved by a third reviewer. A random effects meta-analysis was performed to determine the change in outcomes over follow-up of 3, 6, and 12 months.

RESULTS

Of the 4758 eligible studies, 26 met the inclusion criteria, including nine studies that recruited 488 transgender men and 593 women in which data were meta-analyzed. There was heterogeneity in study design, populations, gender-affirming hormone therapy routes, and dosing. At 12 months after initiating gender-affirming hormone therapy, serum creatinine increased by 0.15 mg/dl (95% confidence interval, 0.00 to 0.29) in 370 transgender men and decreased by -0.05 mg/dl (95% confidence interval, -0.16 to 0.05) in 361 transgender women. No study reported the effect of gender-affirming hormone therapy on albuminuria, proteinuria, cystatin C, or measured GFR.

CONCLUSIONS

Gender-affirming hormone therapy increases serum creatinine in transgender men and does not affect serum creatinine in transgender women. The effect on gender-affirming hormone therapy on other kidney function biomarkers and measured GFR is unknown.

CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER

Change in Kidney Function Biomarkers in Transgender Persons on Gender Affirmation Hormone Therapy-A Systematic Review and Meta-Analysis, CRD42020214248.

A Retrospective Analysis of Creatinine-Based Kidney Function With and Without Sex Assigned at Birth Among Transgender Adults

BACKGROUND

Clinicians use sex-based kidney function estimating equations, but the appropriate sex modifier for transgender adults undergoing hormone therapy (HT) is undetermined.

OBJECTIVES

Compare median estimated creatinine clearance (eCrCL; Cockcroft-Gault) and estimated glomerular filtration rates (eGFRs; Modification of Diet in Renal Disease [MDRD] and Chronic Kidney Disease Epidemiology Study [CKD-EPI]) before and during HT when estimated with and without sex assigned at birth.

METHODS

Single-system retrospective cohort study of transgender adults (2007-2017) prescribed ≥90 days HT (index date = first order) and measured serum creatinine ≤6 months pre-index date (baseline) and ≤12 months post-index date. We grouped patients based on testosterone or estrogen treatment and compared eCrCL and eGFRs at baseline up to 6-12 months post-index date using equations based on sex assigned at birth (female or male modifier in testosterone or estrogen groups, respectively) or gender identity (male or female modifier in testosterone or estrogen groups, respectively). We used Wilcoxon signed-rank tests (Bonferroni correction) for all comparisons.

RESULTS

In total, 29 (median age 26 years, follow-up 259 days) and 41 patients (29 years, 250 days) were prescribed testosterone or estrogen, respectively. In the testosterone group, the maximum eCrCL and eGFR changes based on sex assigned at birth were -14%, P = 0.0181; -18%; P = 0.0009, respectively, and based on gender identity were +5%, P > 0.025 and +11%, P = 0.0094, respectively. In the estrogen group, eCrCL or eGFRs based on sex assigned at birth did not change from baseline but based on gender identity were -17%, P < 0.0001 and -26%, P < 0.0001, respectively.

CONCLUSION AND RELEVANCE

Female-based equations may underestimate kidney function in transgender adults undergoing testosterone or estrogen treatment. Prospective cohort studies are needed to confirm the clinical significance of these findings.

Does Gender Affirming Hormone Therapy Increase the Risk of Kidney Disease?

Kidney health and manifestation of disease in transgender men, women, and nonbinary individuals are not well understood. Transgender individuals commonly receive gender-affirming hormone therapy (GAHT) to align their outward appearance with their gender. Recent attention to the differences in fundamental kidney parameters has identified that transgender individuals may manifest levels of these biomarkers differently than their cisgender counterparts. Improving understanding of the differences in biomarkers and in the development of kidney disease is essential to providing appropriate kidney care to this vulnerable population. In this review, we introduce the current information related to GAHT and kidney health and highlight the significant gaps in our understanding of how GAHT may affect kidney physiology and pathophysiology.

When Hypertension Grows Up: Implications for Transitioning Care of Adolescents and Young Adults With Hypertension From Pediatric to Adult Health Care Providers

Hypertension (HTN) is an important cause of morbidity and mortality in children as well as adults. HTN and related adverse cardiovascular health develop and progress on a continuum across an individual's life course. Pediatric HTN, or even isolated elevated blood pressure as a child, increases the risk of sustained HTN and cardiovascular disease in later adulthood. Transitioning the care of adolescents and young adults who have HTN is an important but unmet health care need that could potentially have a dramatic effect on mitigating the risk of cardiovascular disease in adulthood. However, very little has been published about the transition process in this population, and considerable gaps in the field remain. We discuss the epidemiology, etiology, and management approach in youth with HTN and how they differ from adults. We contextualize HTN and cardiovascular health on a continuum across the life course. We discuss key considerations for the transition process for adolescents and young adults with HTN including the major barriers that exist. Finally, we review key immediate health care needs that are particularly important around the time of the transfer of care.

Sex and Gender Differences in Kidney Transplantation

Sex and gender often are used interchangeably, but are two distinct entities, with sex being the biological attribute and gender including the social, psychological, and cultural aspects of one's identity. Kidney transplantation has been proven to be the best treatment for end-stage kidney disease, improving both quality of life and life-expectancy for most patients. However, gender disparities in access to and outcomes of kidney transplantation remain despite the plethora of evidence showing the advantages of kidney transplantation to our patients. Data have shown that women are less likely to be waitlisted for a kidney transplant and to receive a deceased donor or a living donor kidney. On the other hand, women are more likely than men to become living kidney donors. Although some state the latter is the result of the female gender to nurture and care for loved ones, others believe this observation is because women often are incompatible with their spouse or child because pregnancy is a strong sensitizing event, which stems from the biological rather than the social differences between the sexes. Influence of sex and gender is not limited to access to kidney transplantation, but rather exist in other areas of transplant medicine, such as the difference observed in transplant outcomes between the sexes, variability in immunosuppression metabolism, and even in more contemporary areas such as recent data showing sex-based differences in outcomes of kidney transplant recipients with coronavirus disease-2019, with males having an increased incidence of acute kidney injury and death.

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.

National Kidney Foundation Laboratory Engagement Working Group Recommendations for Implementing the CKD-EPI 2021 Race-Free Equations for Estimated Glomerular Filtration Rate: Practical Guidance for Clinical Laboratories

Recognizing that race is a social and not a biological construct, healthcare professionals and the public have called for removal of race in clinical algorithms. In response, the National Kidney Foundation and the American Society of Nephrology created the Task Force on Reassessing the Inclusion of Race in Diagnosing Kidney Diseases to examine the issue and provide recommendations. The final report from the Task Force recommends calculating estimated glomerular filtration rate (eGFR) without a race coefficient using the recently published CKD-EPI 2021 creatinine and creatinine-cystatin C equations. The Task Force recommends immediately replacing older eGFRcr equations (MDRD Study and CKD-EPI 2009) with the new CKD-EPI 2021 equation. In a 2019 survey by the College of American Pathologists, 23% of 6200 laboratories reporting eGFRcr used an incorrect equation that is not suitable for use with standardized creatinine measurements, 34% used the CKD-EPI 2009 equation and 43% used the MDRD Study 2006 equation re-expressed for standardized creatinine measurement. Rapid transition to using the CKD-EPI 2021 equation is an opportunity for laboratories to standardize to a single equation to eliminate differences in eGFRcr due to different equations used by different laboratories, and to report eGFR without use of race. We provide guidance to laboratories for implementing the CKD-EPI 2021 equations for both eGFRcr and eGFRcr-cys.

The Effect of Gender-Affirming Hormone Therapy on Serum Creatinine in Transgender Individuals

OBJECTIVE

To describe the changes in serum creatinine (Cr) levels after the initiation of gender-affirming hormone therapy (GAHT) in transgender individuals to better understand the expected changes and interpretation of laboratory values in this population.

METHODS

A retrospective chart review of all adult transgender patients initiated on GAHT at Mayo Clinic from January 2011 to October 2019 was completed. Laboratory values were obtained prior to initiating GAHT and at 3, 6, and 12 months after initiating GAHT. Baseline Cr values were compared with Cr values at 3, 6, and 12 months after initiating GAHT in transgender men (TM) on testosterone and transgender women (TW) on estradiol and antiandrogens.

RESULTS

A total of 84 TW (median age of 30 years) and 24 TM (median age of 23 years) were included for analysis. Following a matched pair analysis of TW, Cr values were found to be significantly decreased by -0.03 at 3 months (P = .04), -0.10 at 6 months (P < .01), and -0.07 at 12 months (P < .01) compared with baseline values. Following a matched pair analysis of TM, Cr values were found to be significantly increased, on average, by 0.14 at 3 months (P = .04), 0.21 at 6 months (P = .016), and 0.15 at 12 months (P = .003) compared with baseline values.

CONCLUSION

In TW and TM, a change in Cr level was seen as early as 3 months toward their affirmed gender after initiating GAHT. Clinicians can use Cr levels established at 6 months as new baseline values, as these changes continue to persist up to 12 months.

Transgender Person and Pre-Exposure Prophylaxis for HIV: A Renal Dilemma

Sexual health care for transgender people is often inadequate and not addressed. Targeted prevention approaches that respond to the specific needs of transgender individuals are essential to reducing HIV infections. HIV prophylaxis is a proven intervention in the prevention of HIV among high-risk populations. However, creatinine clearance is one major determining factor in prescribing HIV pre-exposure prophylaxis. One of the variables used in the equation to calculate creatinine clearance is gender. Additionally, regarding transgender people, gender-affirming hormonal therapy also alters the clearance by modifying other variables, such as muscle mass. Here, we present the case of a 58-year-old designated female at birth, who transitioned to male 15 months ago, currently using testosterone, and had presented to the clinic requesting HIV pre-exposure prophylaxis, due to his anticipation of new sexual partners soon. He was initially denied HIV pre-exposure prophylaxis, due to lower estimated creatinine clearance when calculated per his natal assigned gender. The transgender population requires effective HIV pre-exposure prophylaxis, dependent on creatinine clearance, that is dictated by many factors, considering the high prevalence rate. Therefore, validation of eGFR equations in the transgender population is of utmost importance to ensure optimal decision-making and provision of health care.