Associations of Community Water Lead Concentrations with Hemoglobin Concentrations and Erythropoietin-Stimulating Agent Use among Patients with Advanced CKD

Abstract

Significance Statement It is unknown whether low levels of lead exposure, such as those commonly encountered in drinking water systems, have adverse effects. Using data from patients initiating dialysis in the United States over the last 15 years, the authors found those living in cities with higher lead levels in the drinking water supply had significantly lower hemoglobin concentrations and more erythropoietin stimulating agent use. These associations were observed at lead levels significantly below those that the Environmental Protection Agency mandates as actionable. Whether such levels of lead exposure similarly associate with other lead-related diseases will require further study. The authors’ analysis suggests that for patients with kidney disease, there may be no safe amount of lead in drinking water. Background Although patients with kidney disease may be particularly susceptible to the adverse health effects associated with lead exposure, whether levels of lead found commonly in drinking water are associated with adverse outcomes in patients with ESKD is not known. Methods To investigate associations of lead in community water systems with hemoglobin concentrations and erythropoietin stimulating agent (ESA) use among incident patients with ESKD, we merged data from the Environmental Protection Agency (EPA) Safe Drinking Water Information System (documenting average 90 th percentile lead concentrations in community water systems during 5 years before dialysis initiation, according to city of residence) with patient-level data from the United States Renal Data System. Results Among 597,968 patients initiating dialysis in the United States in 2005 through 2017, those in cities with detectable lead levels in community water had significantly lower pre-ESKD hemoglobin concentrations and more ESA use per 0.01 mg/L increase in 90 th percentile water lead. Findings were similar for the 208,912 patients with data from the first month of ESKD therapy, with lower hemoglobin and higher ESA use per 0.01 mg/L higher lead concentration. These associations were observed at lead levels below the EPA threshold (0.015 mg/L) that mandates regulatory action. We also observed environmental inequities, finding significantly higher water lead levels and slower declines over time among Black versus White patients. Conclusions This first nationwide analysis linking EPA water supply records to patient data shows that even low levels of lead that are commonly encountered in community water systems throughout the United States are associated with lower hemoglobin levels and higher ESA use among patients with advanced kidney disease.

Topics & Concepts