Integrating kidney function assessment into the clinical interpretation of plasma Alzheimer's disease biomarkers.

As plasma biomarkers like p-tau217 move towards clinical use in Alzheimer's disease (AD), it is important to understand how kidney function may influence their accuracy. Even mild chronic kidney disease (CKD) can alter biomarker levels, potentially impacting test performance. While accounting for renal function may improve specificity, it could reduce sensitivity without greatly changing overall diagnostic accuracy. Most studies focus on mild CKD, leaving gaps in understanding severe CKD-especially in real-world settings like primary care. Including renal indices such as eGFR in diagnostic models could help improve interpretation and minimize misclassification in older adults, where CKD is common.