Association Between Blood Lead Levels and Diabetic Kidney Disease: A Cross-sectional Analysis of NHANES Data (1999-2018).

Background: The relationship between heavy metals, particularly lead (Pb), and diabetic kidney disease (DKD) remains unclear, especially regarding exposure thresholds. This study investigates the association between blood Pb levels and DKD risk using data from the National Health and Nutrition Examination Survey (NHANES) from 1999 to 2018.

Methods: A total of 1,343 participants were included, with 508 diagnosed with DKD. Baseline characteristics were compared between DKD and non-DKD groups. Multivariate generalized linear models (GLMs) and weighted logistic regression were used to assess correlations between blood Pb levels and DKD risk. A nomogram was developed to evaluate the predictive power of significant clinical characteristics.

Results: Key clinical characteristics, including age, marital status, and serum Pb levels, differed significantly between DKD and non-DKD groups. Serum Pb was identified as a significant risk factor (ORs: 1.18-1.39, p < 0.01). The nomogram demonstrated good predictive accuracy (AUC = 0.717).

Conclusion: Elevated blood Pb levels are significantly associated with DKD, with a non-linear relationship and a defined threshold. These findings highlight the potential role of Pb exposure in DKD pathogenesis and suggest the utility of blood Pb monitoring in diabetic patients.