Reduced kidney function associated with increased levels of dementia-related blood biomarkers: JAMA

Previous studies have mentioned that there is an association between kidney functioning and AD risk but there needs to be more data in this context to clarify further. A precise question here is, "Whether kidney function is related to AD/dementias and with blood biomarkers related to dementia (neurofilament light [NfL], phosphorylated tau181 [p-tau181], and glial fibrillary acidic protein [GFAP])?"

Evaluating further, a study was done by a team of researchers led by Stocker et al. and colleagues from Network Aging Research and the German Cancer Research Center to add data to the background mentioned above.

The study summary includes the following:

• This was a population-based cohort study and a nested case-control study.
• Nine thousand nine hundred forty participants in Germany were enrolled (2000-2002).
• The participants were followed up for 17 years.
• Participants were included if the information related to the status of dementia and creatinine/cystatin C measurements were available.
• The measurements of NfL, p-tau181 and GFAP were obtained from blood samples.
• There were 6256 participants with a mean age of 61.7 years, constituting 54.4%.
• Five hundred ten had all-cause dementia diagnosis within a baseline of 17 years.
• Seven hundred sixty-six participants were included in the dementia-related blood biomarker nested case-control sample.
• At baseline, the impaired kidney function was not associated with an increased risk of all-cause dementia, AD and vascular dementia diagnosis, having hazard ratios of 0.95, 0.94 and 1.06 respectively.
• The cross-sectional analysis revealed impairment in the function of the kidney was associated with NfL and p-tau181 levels in the blood (NfL: β = 0.47; p-tau181: β = 0.21 ) as revealed in cross-sectional analysis.
• Significant associations with glial fibrillary acidic protein (GFAP) levels were evident among men only (men: β = 0.31, women: β = −0.12 ) after adjusting for age and sex,

To conclude, reduced kidney function increases levels of dementia-related blood biomarkers, but it is not associated with the risk of dementia. Kidney function may influence the accuracy of dementia-related blood biomarkers.

Researchers mentioned kidney function should be considered in clinical translation.

Further reading:

Stocker H et al. Association of Kidney Function With Development of Alzheimer Disease and Other Dementias and Dementia-Related Blood Biomarkers. JAMA Netw Open. 2023;6(1):e2252387. doi:10.1001/jamanetworkopen.2022.52387