A Blood Test Can Estimate Alzheimer's Disease Risk in Cognitively Healthy Individuals Up to a Decade Before Symptom Onset

• The study followed nearly 1,000 cognitively healthy individuals for 12 years. The findings reinforce the potential of blood-based biomarkers to stratify the long-term risk of clinical progression to Alzheimer's disease.
• Conducted by researchers from CIEN and the Reina Sofía Foundation, the study has been published in Alzheimer's & Dementia, one of the leading international scientific journals in the field of Alzheimer's research.

A study conducted by researchers from CIEN (Center for Research on Neurological Diseases) and the Reina Sofía Foundation, led by Dr. Jesús Silva Rodríguez, Coordinator of the Neuroimaging Platform, has shown that measuring the novel blood biomarker %p-tau217 can estimate the long-term risk of developing the clinical symptoms of Alzheimer's disease in cognitively healthy older adults. The study has been published in Alzheimer's & Dementia: the Journal of the Alzheimer's Association.

The research included nearly 1,000 cognitively healthy participants recruited in the Madrid region, who underwent annual assessments at the Reina Sofía Foundation Alzheimer Center over a follow-up period of up to 12 years. The findings represent an important step towards the integration of blood-based biomarkers into clinical practice by providing a minimally invasive tool for the early identification of individuals at increased risk of developing Alzheimer's disease.

According to Dr. Jesús Silva Rodríguez, the study's principal investigator, "the main strength of this study lies in the high negative predictive value of plasma biomarkers. A negative test result allows us to state, with more than 90% reliability, that an individual is unlikely to develop clinical symptoms over the following decade. This will enable healthcare resources and follow-up efforts to be focused on those who are genuinely at risk."

Towards Precision Medicine for the Early Detection and Prevention of Alzheimer's Disease

For Dr. Pascual Sánchez-Juan, Scientific Director of CIEN and senior author of the study, "this research marks an important shift: blood-based biomarkers are no longer useful only for detecting the biological changes associated with Alzheimer's disease, but also for estimating the long-term risk of clinical progression in asymptomatic individuals. At present, their value lies less in deterministically predicting who will develop the disease and more in reliably identifying the large proportion of individuals at very low risk, while improving the selection of those who may benefit from closer monitoring or participation in prevention studies."

Overall, these findings represent a major step towards earlier, more accessible, and minimally invasive detection of Alzheimer's disease. The ability to identify individuals at increased risk through a simple blood test will facilitate the development of preventive strategies, improve participant selection for clinical trials, and support the early implementation of disease-modifying therapies at the stage when they are most likely to provide the greatest benefit.