Examining the Potential Impact of Race Multiplier Utilization in Estimated Glomerular Filtration Rate Calculation on African-American Care Outcomes

Background: Advancing health equity entails reducing disparities in care. African-American patients with chronic kidney disease (CKD) have poorer outcomes, including dialysis access placement and transplantation. Estimated glomerular filtration rate (eGFR) equations, which assign higher eGFR values to African-American patients, may be a mechanism for inequitable outcomes. Electronic health record-based registries enable population-based examination of care across racial groups.

Objective: To examine the impact of the race multiplier for African-Americans in the CKD-EPI eGFR equation on CKD classification and care delivery.

Design: Cross-sectional study SETTING: Two large academic medical centers and affiliated community primary care and specialty practices.

Participants: A total of 56,845 patients in the Partners HealthCare System CKD registry in June 2019, among whom 2225 (3.9%) were African-American.

Measurements: Exposures included race, age, sex, comorbidities, and eGFR. Outcomes were transplant referral and dialysis access placement.

Results: Of 2225 African-American patients, 743 (33.4%) would hypothetically be reclassified to a more severe CKD stage if the race multiplier were removed from the CKD-EPI equation. Similarly, 167 of 687 (24.3%) would be reclassified from stage 3B to stage 4. Finally, 64 of 2069 patients (3.1%) would be reassigned from eGFR > 20 ml/min/1.73 m² to eGFR ≤ 20 ml/min/1.73 m², meeting the criterion for accumulating kidney transplant priority. Zero of 64 African-American patients with an eGFR ≤ 20 ml/min/1.73 m² after the race multiplier was removed were referred, evaluated, or waitlisted for kidney transplant, compared to 19.2% of African-American patients with eGFR ≤ 20 ml/min/1.73 m² with the default CKD-EPI equation.

Limitations: Single healthcare system in the Northeastern United States and relatively small African-American patient cohort may limit generalizability.

Conclusions: Our study reveals a meaningful impact of race-adjusted eGFR on the care provided to the African-American CKD patient population.