Abstract P416: Higher Household Income is Protective Against Chronic Kidney Disease Among White but Not Black Adults: An Analysis of 2017-2020 NHANES

Abstract

Introduction: Chronic kidney disease (CKD) disproportionately affects Black adults in the U.S. Prior work suggests that lower income is a risk factor for CKD among Black but not White adults; however, this has not been examined in a nationally representative population, using the updated, race-free kidney function equation. Objective: To examine the relationship between household income and CKD between Black and White adults. Methods: We used data from the 2017-2020 NHANES. CKD was defined as an estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73m 2 based on the race-free CKD-EPI equation and/or a urine albumin-creatinine ratio >30 mg/g. The poverty income ratio (PIR) (ranging from 0 to ≥5) was reported in NHANES (calculated as a multiple of interviewees self-reported income in dollars as compared to the federal poverty line). We examined the association between PIR and CKD using survey-weighted Poisson regression models, adjusted for age, sex, education, marital status, and medical comorbidities. We also examined how this association differed between Black and White adults aged ≥18 years old in separate subgroup analyses via interaction terms. Results: The weighted sample was 51.7% female, 15.5% Black, and 84.5% White with mean age (±SE) of 47.5±0.3 years. In the total sample, and among White adults, higher household income was associated with a lower prevalence of CKD ( Table ). A one-unit higher PIR was associated with a 11% (95% CI: 5%, 16%) lower prevalence of CKD in the total sample and a 12% (95% CI: 6%, 18%) lower prevalence of CKD among White adults. However, this association was not significant for Black adults. The interaction term for race and income was significant ( P = 0.001). Conclusion: Higher income was associated with a lower risk of CKD among White, but not Black adults. Further work is needed to characterize the complex relationship between socioeconomic status and race to address disparities in CKD.