NASHVILLE, TN — How chronic kidney disease (CKD) affects Alzheimer’s disease (AD) plasma biomarkers is poorly understood.
A study team led by the Vanderbilt University School of Medicine and the Tennessee Valley VA Healthcare System, both in Nashville, tested whether kidney function decline affects the predictive accuracy of plasma biomarkers on neuropsychological or neuroimaging outcomes. The results were published in the Alzheimer’s & Dementia journal.1
Included were 333 nondemented older adults. Linear regressions related plasma glial fibrillary acidic protein, neurofilament light chain (NfL), amyloid beta 42 and phosphorylated tau231, with a blood-based biomarker x estimated glomerular filtration rate (eGFR) interaction term, to cross-sectional and longitudinal (mean follow-up time = 6.4 ± 2.8 years) neuropsychological and neuroimaging outcomes.
Results indicated that plasma NfL interacted with eGFR on the longitudinal trajectory of nearly all neuropsychological outcomes (p values < 0.02) and several neuroimaging outcomes (p values < 0.02). “Associations were stronger in individuals with no CKD/stage 1 and stage 2 CKD, while associations were weaker or not significant in individuals with stage 3 CKD,” the researchers pointed out.
They explained that, among older adults free of severe CKD, the ability of plasma NfL to predict key AD-related biomarker outcomes was moderated by renal function.
“Reduced kidney function was associated with increased blood biomarker levels,” the authors concluded. “The predictive accuracy of neurofilament light chain was reduced in participants with kidney dysfunction. Even mild kidney dysfunction can affect blood biomarkers of Alzheimer’s disease.”
- Bolton CJ, Zhang P, Nair D, Liu D, et. Al. Mild kidney dysfunction affects the predictive accuracy of blood-based biomarkers for neuropsychological and neuroimaging outcomes over a 9 year follow-up period. Alzheimers Dement. 2025 Sep;21(9):e70651. doi: 10.1002/alz.70651. PMID: 40970383.
