This cross-sectional sub-study will use a subset of the main study cohort of transgender (TG) or non-binary (NB) individuals to evaluate the relationships between self-reported exogenous hormone use, endogenous hormone values (serum estradiol, estrone, free/total testosterone), renal biomarkers, drug levels (measured by tenofovir diphosphate, TFV-DP, and emtricitabine triphosphate, FTC-TP, on dried blood spot cards and urine) and directly measured renal function (iohexol clearance).
