Clinical Report: Plasma pTau217 Cutoffs for Clinical Use

Overview

Revise to specify how the double-cutoff strategy in obesity increases the need for confirmatory imaging.

Background

Plasma p-tau217 is a promising biomarker for Alzheimer's disease, but its diagnostic utility can be affected by comorbid conditions such as kidney dysfunction and anemia. Understanding how these factors influence p-tau217 levels is critical for accurate diagnosis and management of Alzheimer's disease, particularly in diverse patient populations.

Data Highlights

Key Findings

• Kidney dysfunction and anemia elevate baseline plasma p-tau217 levels.
• Subgroup-specific cutoffs improved diagnostic accuracy significantly in chronic kidney disease and anemia.
• The double-cutoff strategy reduced false classifications but resulted in 39% intermediate results requiring further imaging.
• Optimal cutoffs provided a favorable balance of diagnostic accuracy and cost efficiency in chronic kidney disease and anemia.
• Plasma p-tau217 concentrations were inversely associated with estimated glomerular filtration rate, body mass index, and hemoglobin.

Clinical Implications

Highlight the importance of diverse patient populations in implementing findings.

Conclusion

The study underscores the importance of biologically informed approaches in the use of plasma p-tau217 for Alzheimer's disease diagnosis, particularly in patients with comorbid conditions. Further validation in diverse populations is necessary to generalize these findings.

References

1. Yun J, et al., JAMA Neurology, 2025 -- Plasma Phosphorylated Tau 217 Cutoffs for Amyloid Pathology and Kidney Function, Body Mass Index, and Anemia
2. Acta Neuropathologica, 2021 -- Plasma p-tau231: An Emerging Biomarker for Early Detection of Alzheimer’s Disease Pathology
3. Brain, 2021 -- An In-Depth Evaluation of Major Plasma Phosphorylated Tau 217 Biomarker Assays
4. Brain, 2021 -- Plasma phosphorylated tau217 strongly associates with memory deficits in the Alzheimer’s disease spectrum
5. Criteria for Diagnosis and Staging of Alzheimer's Disease | alz.org
6. Acta Neuropathologica — CSF p-tau205: An Indicator of Tau Pathology in Alzheimer’s Disease
7. Plasma Phosphorylated Tau 217 and Amyloid Burden in Older Adults Without Cognitive Impairment: A Meta-Analysis
8. Criteria for Diagnosis and Staging of Alzheimer's Disease | alz.org
9. Plasma Phosphorylated Tau 217 Cutoffs for Amyloid Pathology and Kidney Function, Body Mass Index, and Anemia | Reproductive Health | JAMA Neurology | JAMA Network