Kidney function may affect Alzheimer’s blood biomarkers
People with lower kidney function may have higher levels of several blood markers often used in research on Alzheimer’s disease and related dementias. This is shown in a new systematic review and meta‑analysis published in The Journal of the American Society of Nephrology.
The study brought together results from 93 previously published studies including more than 62,000 adults from 21 countries. The researchers examined whether kidney function, most often measured by estimated glomerular filtration rate (eGFR), was linked to common biomarkers such as amyloid‑β, tau, neurofilament light (NfL) and glial fibrillary acidic protein (GFAP) in blood or cerebrospinal fluid (CSF).
“We saw that lower kidney function was consistently associated with higher levels of several blood biomarkers. This pattern appeared both in unadjusted and adjusted analyses” says Hong Xu, assistant professor at the Department of Neurobiology, Care Sciences and Society.
According to the study, each small decrease in eGFR—1 ml/min/1.73m²—was linked to slightly higher concentrations of NfL, GFAP and amyloid‑β40 in blood. Findings for CSF biomarkers were more mixed and generally showed no clear association.
May affect the interpretation of the results
Because many dementia biomarkers are increasingly being used in clinical and research settings, understanding how other health conditions affect their levels is important.
“Our findings suggest that kidney function may influence blood biomarker concentrations, which could be relevant when interpreting results in both research and clinical practice,” says Hong Xu.
The authors note that more work is needed to clarify why these associations occur and how they should be considered in future diagnostic strategies.
Funding for this paper included the Center for Innovative Medicine Foundation (CIMED, FoUI-1002840), Åke Wibergs Stiftelse (M24-0221), the Swedish Research Council (2022-01428), Alzheimerfonden (AF-1032116), Njurfonden, and Karolinska Institutet’s Foundations.
Publication
Kidney Function and Blood and Cerebrospinal Fluid Biomarkers in Alzheimer's Disease and Related Dementias: Systematic Review and Meta-Analysis
Lin Y, Zhao Z, Zhu N, Ptacek SG, Carrero JJ, Bruchfeld A, Eriksdotter M, Mielke MM, Brusselaers N, Xu H, Journal of the American Society of Nephrology, online January 26, 2026, doi: 10.1681/ASN.0000001007