Alzheimer's Risk Predicted by Blood Test Years Before Symptoms Appear
A new blood test may identify the risk of Alzheimer's-related cognitive decline up to a decade before symptoms manifest. Individuals with high levels of the p-tau217 biomarker show a significant risk.
A novel blood test could help predict future cognitive decline associated with Alzheimer's disease up to ten years before symptoms emerge, researchers report. The study, presented at the Alzheimer's Association International Conference (AAIC) in London and simultaneously published in JAMA, found that elevated levels of the blood biomarker p-tau217 predict faster cognitive decline.
Research indicated that symptom-free older adults with very high p-tau217 levels had an estimated 78% risk of developing cognitive impairment over a 10-year period. This risk remained significant even for those with moderately elevated levels. The blood test provided insights into future risk beyond what brain scans and genetic testing offer.
According to the researchers, these findings could aid in the early identification of at-risk individuals. This could facilitate recruitment for preventive treatment trials and guide earlier treatment and monitoring decisions. The test measures levels of phosphorylated tau protein (p-tau217) in the blood, a marker strongly linked to Alzheimer's pathology.
The study analyzed data from nearly 2,700 cognitively unimpaired adults, with an average age of 70. Participants were followed for an average of nearly five years, with some followed for over a decade. The results support the notion that early detection and intervention are crucial for preventing and managing Alzheimer's disease.