Racial Disparities in Nephrology Consultation and Disease Progression among Veterans with CKD: An Observational Cohort Study

Abstract

Background: Incident rates of ESRD are much higher among black and Hispanic patients than white patients. Access to nephrology care before progression to ESRD is associated with better clinical outcomes among patients with CKD. However, it is unknown whether black or Hispanic patients with CKD experience lower pre-ESRD nephrology consultation rates compared with their white counterparts, or whether such a disparity contributes to worse outcomes among minorities.

Methods: We assembled a retrospective cohort of patients with CKD who received care through the Veterans Health Administration from 2003 to 2015, focusing on individuals with incident CKD stage 4 who had an initial eGFR≥60 ml/min per 1.73 m² followed by two consecutive eGFRs<30 ml/min per 1.73 m². We repeated analyses among individuals with incident CKD stage 3. Outcomes included nephrology provider referral, nephrology provider visit, progression to CKD stage 5, and mortality.

Results: We identified 56,767 veterans with CKD stage 4 and 640,704 with CKD stage 3. In both cohorts, rates of nephrology referral and visits were significantly higher among black and Hispanic veterans than among non-Hispanic white veterans. Despite this, both black and Hispanic patients experienced faster progression to CKD stage 5 compared with white patients. Black patients with CKD stage 4 experienced slightly lower mortality than white patients, whereas black patients with CKD stage 3 had a small increased risk of death.

Conclusions: Black or Hispanic veterans with CKD are more likely than white patients to see a nephrologist, yet are also more likely to suffer disease progression. Biologic and environmental factors may play a bigger role than nephrology consultation in driving racial disparities in CKD progression.

Keywords: chronic kidney disease; end stage kidney disease; health disparities; nephrology; outcomes.

Graphical abstract

Figure 1.

56,767 Veterans with incident CKD stage 4 met inclusion criteria for the study. Process for assembling cohort of individuals with CKD stage 4 who received care in the VHA. eGFR in ml/min per 1.73 m² (calculated using the CKD Epidemiology Collaboration equation).

Figure 2.

Non-Hispanic white patients with CKD stage 4 experienced significantly improved survival without advancing to CKD stage 5 compared to Non-Hispanic blacks, Hispanic whites, and Hispanic blacks. Non-Hispanic blacks had the greatest overall survival. (A and B) Time to event analyses for the CKD stage 4 cohort. Risk set numbers at day 0 are smaller than totals from Table 1 because some members of the cohort achieved the outcome on day 0.