Epidemiology

Background

Few studies have evaluated associations between low to moderate arsenic levels and chronic kidney disease (CKD). The objective was to evaluate the associations of inorganic arsenic exposure with prevalent and incident CKD in American Indian adults.

Methods

We evaluated the associations of inorganic arsenic exposure with CKD in American Indians who participated in the Strong Heart Study (SHS) in 3,851 adults aged 45–74 years in a cross-sectional analysis, and 3,119 adults with follow-up data in a prospective analysis. Inorganic arsenic, monomethylarsonate, and dimethylarsinate were measured in urine at baseline. CKD was defined as eGFR≤60 mL/min/1.73m2, kidney transplant or dialysis.

Results

CKD prevalence was 10.3%. The median (IQR) concentration of inorganic plus methylated arsenic species (total arsenic) in urine was 9.7 (5.8, 15.7) μg/L. The adjusted OR (95% CI) of prevalent CKD for an interquartile range in total arsenic was 0.7 (0.6, 0.8), mostly due to an inverse association with inorganic arsenic (OR 0.4 (0.3, 0.4)). Monomethylarsonate and dimethylarsinate were positively associated with prevalent CKD after adjustment for inorganic arsenic (OR 3.8 and 1.8). The adjusted HR of incident CKD for an IQR in ΣAs was 1.2 (1.03, 1.41). The corresponding HR for inorganic arsenic, monomethylarsonate and dimethylarsinate were 1.0 (0.9, 1.2), 1.2 (1.00, 1.3) and 1.2 (1.0, 1.4).

Conclusions

The inverse association of urine inorganic arsenic with prevalent CKD suggests that kidney disease affects excretion of inorganic arsenic. Arsenic species were positively associated with incident CKD. Studies with repeated measures are needed to further characterize the relationship between arsenic and kidney disease development.

25929811

PMC4844343

Journal Article

CDC Public Access