Estimated glomerular filtration rate and serum neurofilament light chain: insight from NHANES

The neurofilament light chain is a protein biomarker associated with neurodegenerative diseases. Neurofilament light chain levels may increase as kidney function declines due to reduced clearance. However, the relationship between estimated glomerular filtration rate (eGFR) and serum neurofilament light chain (sNfL) has not been extensively studied. Therefore, the objective of this study was to examine the association between eGFR and sNfL levels. Health survey data from 2071 eligible participants in the National Health and Nutrition Examination Survey (NHANES) were used in three multivariate-adjusted weighted linear regression models to analyze the correlation between eGFR and sNfL. Subsequently, segmental linear regression analysis was employed to determine the inflection point of eGFR. Finally, through subgroup analysis, we aimed to assess the impact of all covariates on the association between eGFR and sNfL. According to our results, sNfL levels decreased as eGFR increased. The segmental linear regression model analysis identified an inflection point at 59.9. When eGFR reached 59.9 or exceeded it, each unit increase in eGFR was associated with a 1 pg/mL decrease in sNfL (β = −0.1, P = 0.01). Furthermore, subgroup analysis revealed that hypertension exhibited a significant interaction with the association between eGFR and sNfL (P = 0.01). These findings suggest that eGFR holds promise as a potential marker for neurodegenerative disorders, and hypertension could affect this association to some extent. Moreover, these results could have significant implications for the early detection and prevention of neurodegenerative diseases in patients with kidney disease. However, further research is needed to corroborate these results and elucidate the underlying mechanisms.