eGFR Discordance and its Association with Outcomes following Allogeneic Hematopoietic Stem Cell Transplantation and Adoptive T-Cell Therapies

Background: Discordance between estimated glomerular filtration rate (eGFR) based on serum creatinine (eGFR cr ) versus cystatin C (eGFR cys ) is associated with adverse outcomes in patients with and without cancer. We hypothesized that eGFR discordance is associated with acute kidney injury (AKI) and death following hematopoietic stem cell transplant (HSCT) or receipt of adoptive T-cell therapies. Methods: We conducted a multicenter study of adults receiving allogeneic HSCT and adoptive T-cell therapies who had paired serum creatinine and cystatin C values obtained in the 30 days preceding conditioning or lymphodepleting chemotherapy. The primary exposure was eGFR discordance, defined as eGFR cys ≥30% lower than eGFR cr . The primary outcome was a composite outcome of AKI (≥50% increase in serum creatinine or receipt of kidney replacement therapy) or death within 90 days following HSCT or adoptive T-cell infusion. Secondary outcomes included time-to-platelet engraftment in HSCT and prolonged cytopenia in adoptive T-cell recipients. We used multivariable logistic regression and cause-specific Cox regression with inverse probability weighting to adjust for confounders. Results: Of 274 patients receiving HSCT (median age 65 years, interquartile range [IQR] 52-71]; 43% female), 86 (31%) had an eGFR discordance. Among 236 adoptive T-cell recipients (median age 67 years, IQR [60-74]; 59% female), 78 (33%) had a discordance in eGFR. eGFR discordance was associated with higher odds of AKI or death in HSCT (odds ratio [OR] 1.75; 95% confidence interval [CI] 1.03-3.02) and adoptive T-cell recipients (OR 2.37; 95% CI 1.12-4.94). However, adjustment for eGFR cr-cys attenuated these associations in both cohorts. eGFR discordance was also associated with slower time-to-platelet engraftment in HSCT recipients and prolonged cytopenia following adoptive T-cell therapy. Conclusions: A pre-treatment eGFR discordance was associated with AKI or death in HSCT and adoptive T-cell recipients; however, this association was attenuated after adjusting for eGFR cr-cys .