The Relationship Between Neighborhood Disadvantage and Kidney Disease Progression in the Chronic Kidney Disease in Children (CKiD) Cohort

Rationale & Objective: To examine the relationship between neighborhood poverty and deprivation, chronic kidney disease (CKD) comorbidities, and disease progression in children with CKD. Study Design: Observational cohort study. Setting & Participants: Children with mild to moderate CKD enrolled in the CKiD (Chronic Kidney Disease in Children) study with available US Census data. Exposure: Neighborhood poverty and neighborhood disadvantage. Outcome: Binary outcomes of short stature, obesity, hypertension, and health care utilization for cross-sectional analysis; a CKD progression end point (incident kidney replacement therapy [KRT] or 50% loss in estimated glomerular filtration rate), and mode of first KRT for time-to-event analysis. Analytical Approach: Cross-sectional analysis of health characteristics at time of first Census data collection using logistic regression to estimate odds ratios. Risk for CKD progression was analyzed using a Cox proportional hazard model. Multivariable models were adjusted for race, ethnicity, sex, and family income. Results: There was strong agreement between family and neighborhood socioeconomic characteristics. Risk for short stature, hospitalization, and emergency department (ED) use were significantly associated with lower neighborhood income. After controlling for race, ethnicity, sex, and family income, the odds of hospitalization (OR, 1.71 [95% CI, 1.08-2.71]) and ED use (OR, 1.56 [95% CI, 1.02-2.40]) remained higher for those with lower neighborhood income. The hazard ratio of reaching the CKD progression outcome for participants living in lower income neighborhoods was significantly increased in the unadjusted model only (1.38 [95% CI, 1.02-1.87]). Likelihood of undergoing a preemptive transplant was decreased with lower neighborhood income (OR, 0.47 [95% CI, 0.24-0.96]) and higher neighborhood deprivation (OR, 0.31 [95% CI, 0.10-0.97]), but these associations did not persist after controlling for participant characteristics. Limitations: Limited generalizability, as only those with consistent longitudinal nephrology care were studied. Conclusions: Neighborhood-level socioeconomic status (SES) was associated with poorer health characteristics and CKD progression in univariable analysis. However, the relationships were attenuated after accounting for participant-level factors including race. A persistent association of neighborhood poverty with hospitalizations and ED suggests an independent effect of SES on health care utilization, the causes for which deserve additional study.