Racial disparities in creatinine-based kidney function estimates among HIV-infected adults

Objective: The aim of our study was to investigate whether current eGFR equations in clinical use might systematically overestimate the kidney function, and thus misclassify CKD status, of Black Americans with HIV. Specifically, we evaluated the impact of removing the race coefficient from the MDRD and CKD-EPI equations on comparisons between Black and White HIV-infected veterans related to: 1) the prevalence of reduced eGFR; 2) the distribution of eGFR values; and 3) the relationship between eGFR and all-cause mortality. Design: Retrospective cohort study. Setting: The Department of Veterans Affairs (VA) HIV Clinical Case Registry (CCR), which actively monitors all HIV-infected persons receiving care in the VA nationally. Patients/Participants: 21,905 treatmentnaïve HIV-infected veterans. Main Outcome Measures: Estimated glomerular filtration rate (eGFR) using the abbreviated Modification of Diet in Renal Disease (MDRD) formula with and without (MDRD-RCR) the race coefficient and allcause mortality. Results: Persons with eGFR <45 mL/ min/1.73m² had a higher risk of death compared with those with eGFR >80 mL/ min/1.73m² among both Blacks (HR=2.8, 95%CI: 2.4-3.3) and Whites (HR=1.9, 95%CI: 1.4-2.6), but the association appeared to be stronger in Blacks (P=.038, test for interaction). Blacks with eGFR 45- 60 mL/min/1.73m² also had a higher risk of death (HR=1.7, 95%CI: 1.4-2.1) but Whites did not (HR=0.86, 95%CI: .67- 1.10; test for interaction: P<.0001). Racial differences were substantially attenuated when eGFR was re-calculated without the race coefficient. Conclusions: Our findings suggest that clinicians may want to consider estimating glomerular filtration rate without the race coefficient in Blacks with HIV.