Mechanism for adverse renal effects from heavy metals exposure in the CRIC study

BACKGROUND: Chronic kidney disease (CKD) poses a major public health challenge, resulting in substantial illness, death, and financial strain. The potential role of environmental factors, such as heavy metal (HM) exposure, in the exacerbation of the disease is increasingly recognized but not well understood. This study aims to shed light on the impact of HMs on the progression of CKD. METHODS: In this study, we examined nail clippings and plasma samples from 20 participants enrolled in the Chronic Renal Insufficiency Cohort (CRIC), a multi-center study designed to investigate risk factors for CKD progression and cardiovascular outcomes. HM concentrations were quantified using inductively coupled plasma mass spectrometry (ICP/MS). We selected participants from two groups based on CKD progression: stable disease (n = 10) and fast-progressing disease (n = 10). We descriptively summarized variables within the groups and used Mann-Whitney and Fisher’s exact tests for between-group comparisons of continuous and categorical variables, respectively. RESULTS: Baseline demographic characteristics differed between stable and fast-progressors, with fast-progressors having higher body mass index (BMI) and higher systolic blood pressure. Distinct patterns in HM concentrations were observed. Subjects with more rapid CKD progression displayed higher median baseline metal burdens (293 µg/g) compared to those with stable disease (267 µg/g), but the differences did not reach statistical significance. Markers of ER stress, mitochondrial stress, and inflammation did not show statistically significant differences. CONCLUSION: This study offers preliminary data regarding a potential association between HM exposure and progression of CKD. Although comparisons did not reach statistical significance, they suggest potential pathways through which HMs may influence disease progression. Future studies with larger cohorts are necessary to validate these findings, improve statistical power, and further elucidate the roles of HMs in CKD progression. This research underscores the importance of considering environmental factors in the management of chronic diseases.