Effect of Hormone Therapy on Renal Function

Study Overview
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Brief Summary
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The purpose of this study is to understand the effects of testosterone or estradiol on kidney function in transgender adolescents and young adults.

Official Title
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The Effects of Hormone Therapy on Renal Hemodynamic Function in Transgender Youth

Conditions
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Transgenderism, Kidney Diseases, Kidney Injury

Intervention / Treatment
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* Diagnostic Test: p-aminohippurate clearance study
* Diagnostic Test: Iohexol infusion


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Identify as transgender Age 17-30 years (inclusive) Plan to start gender affirming hormone therapy (testosterone or estradiol) clinically in ≤ 1 months and remain on for at least 3 months Exclusion Criteria: Cognitive, psychiatric or physical impairment resulting in inability to tolerate the study procedures (e.g. intellectual disability, schizophrenia, hallucinations) Type 1 or Type 2 diabetes Chronic kidney disease, or eGFR <60ml/min/1.73m2 by CKD-EPI formulation Uncontrolled hypertension (resting BP ≥ 140/90 mm/Hg) Allergy to shellfish, iodine or iohexol Currently taking: sulfonamides, procaine, thiazolesulfone and probenecid (renal clearance measurements of PAH cannot be made accurately if individuals are on these medications) Prior gender affirming hormone therapy use Prior gonadectomy Pregnancy

Ages Eligible for Study
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Minimum Age: 17 Years
Maximum Age: 30 Years

Sexes Eligible for Study
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All

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Transgender males<br>Transgender males who are clinically ready to start testosterone | Diagnostic Test: p-aminohippurate clearance study<br>* To measure kidney blood flow, small doses of a substance called p-aminohippurate (PAH) are used.<br>Diagnostic Test: Iohexol infusion<br>* To measure glomerular filtration rate (GFR)<br>|
| Transgender females<br>Transgender females who are clinically ready to start estradiol | Diagnostic Test: p-aminohippurate clearance study<br>* To measure kidney blood flow, small doses of a substance called p-aminohippurate (PAH) are used.<br>Diagnostic Test: Iohexol infusion<br>* To measure glomerular filtration rate (GFR)<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in measured glomerular filtration rate (GFR) |  | Baseline, 3 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in effective renal plasma flow |  | Baseline, 3 months | 
| Change in biomarkers of tubular injury and repair (Neutrophil gelatinase-associated lipocalin [NGAL], Kidney injury molecule-1 [KIM-1], Chitinase-3-like protein 1 [YKL-40]) |  | Baseline, 3 months | 
| Change in fat mass | Quantified noninvasively by ImpediMed SFB7 single channel, tetra polar bioimpedance spectroscopy | Baseline, 3 months | 
| Change in fat-free mass | Quantified noninvasively by ImpediMed SFB7 single channel, tetra polar bioimpedance spectroscopy | Baseline, 3 months | 
| Change in intracellular fluid | Quantified noninvasively by ImpediMed SFB7 single channel, tetra polar bioimpedance spectroscopy | Baseline, 3 months | 
| Change in extracellular fluid | Quantified noninvasively by ImpediMed SFB7 single channel, tetra polar bioimpedance spectroscopy | Baseline, 3 months |