A single blood marker might quietly sign dementia danger many years upfront.
Scientists on the College of California, San Diego, have recognized a blood sign that would forecast dementia danger many years earlier than signs start. Their examine, just lately printed in JAMA Community Open, highlights a protein known as phosphorylated tau 217 (p-tau217), which displays early modifications within the mind linked to Alzheimer’s illness.
Amongst older girls with no indicators of cognitive decline initially of the examine, these with larger ranges of p-tau217 had been way more prone to develop gentle cognitive impairment or dementia years later. In some instances, the sign appeared as much as 25 years earlier than analysis, suggesting that the illness course of might start silently a lot sooner than beforehand understood.
“Our examine suggests we could possibly determine girls at elevated danger for dementia many years earlier than signs emerge,” stated Aladdin H. Shadyab, PhD, MPH, first writer of the examine and UC San Diego affiliate professor of public well being and medication on the Herbert Wertheim Faculty of Public Well being and Human Longevity Science and the Faculty of Medication. “That sort of lengthy lead time opens the door to earlier prevention methods and extra focused monitoring, moderately than ready till reminiscence issues are already affecting each day life.”
Lengthy-Time period Examine Reveals Predictive Biomarker
The evaluation included 2,766 contributors from the Girls’s Well being Initiative Reminiscence Examine, a nationwide undertaking that enrolled girls ages 65 to 79 within the late Nineties and adopted them for so long as 25 years. All contributors had regular cognitive operate at enrollment.
Researchers later examined saved blood samples to measure p-tau217, which displays early Alzheimer’s-related modifications within the mind. Over time, they recognized contributors who developed reminiscence or pondering issues, together with dementia.
Girls with larger p-tau217 ranges initially of the examine had been considerably extra prone to develop dementia later in life. Danger rose steadily alongside biomarker ranges, with the best ranges similar to the best chance of long-term cognitive decline.
The energy of this hyperlink was not uniform throughout all contributors. Increased p-tau217 ranges had been extra strongly tied to worse cognitive outcomes in girls over age 70 in comparison with those that had been youthful at baseline. The affiliation was additionally stronger in girls carrying the APOE ε4 genetic variant, which will increase Alzheimer’s danger.
As well as, p-tau217 extra precisely predicted dementia in girls assigned to estrogen plus progestin hormone remedy in contrast with these given a placebo. Variations had been additionally noticed between white and Black girls, though combining p-tau217 ranges with age improved prediction accuracy in each teams.
Towards Earlier Detection and Prevention
“Blood-based biomarkers like p-tau217 are particularly promising as a result of they’re far much less invasive and doubtlessly extra accessible than mind imaging or spinal fluid assessments,” stated Linda Okay. McEvoy, PhD, senior writer of the examine, senior investigator at Kaiser Permanente Washington Well being Analysis Institute and professor emeritus on the Herbert Wertheim Faculty of Public Well being. “That is necessary for accelerating analysis into the elements that have an effect on danger of dementia and for evaluating methods which will cut back danger.”
At current, blood-based biomarkers usually are not really useful for scientific use in folks with out signs of cognitive impairment. The researchers emphasize that extra research are wanted to find out how p-tau217 testing might be utilized in routine care and whether or not detecting danger earlier can enhance outcomes.
Future work will look at how hormone remedy, genetics, and age-related well being situations work together with plasma p-tau217 over time to affect dementia danger.
“In the end, the aim isn’t just prediction,” Shadyab added, “however utilizing that data to delay or forestall dementia altogether.”
Reference: “Plasma Phosphorylated Tau 217 and Incident Delicate Cognitive Impairment and Dementia in Older Girls” by Aladdin H. Shadyab, Bowei Zhang, Andrea Z. LaCroix, Michelle M. Mielke, Susan M. Resnick, Steve Nguyen, Luigi Ferrucci, Towia A. Libermann, Lengthy Ngo, Ramon Casanova, Alexander P. Reiner, Danni Li, Caroline M. Nievergelt, Adam X. Maihofer, JoAnn E. Manson and Linda Okay. McEvoy, 10 March 2026, JAMA Community Open.
DOI: 10.1001/jamanetworkopen.2026.1295
Disclaimer: Shadyab reviews funding from R01AG079149. Mielke reviews receiving funding from U24 AG082930; grants and contracts from NIH (RF1AG69052, RF1AG077386, RF1AG079397, U19 AG078109, U24 AG082930), DOD (W81XWH2110490), Alzheimer’s Affiliation, and Davos Alzheimer’s Collaborative; consulting charges from Acadia, Althira, Beckman Coulter, Biogen, Cognito Therapeutics, Eisai, Lilly, Merck, Neurogen Biomarking, Novo Nordisk, Roche, Siemens Healthineers; fee from Roche, Novo Nordisk, Biogen, and Medscape; and funds for grant evaluations. Resnick reviews employment by the NIA Intramural Analysis Program through the examine; assist from the McKnight Basis Annual Assembly as a keynote speaker; ISAB member of the Canadian Consortium on Neurodegeneration in Growing old; Exterior Advisory Board Member on the Grownup Growing old Mind Connectome Examine; and ISAB member for Dementia Platforms UK. Ngyuen reviews funding from 5K99AG082863-02. LaCroix reviews funding from grant R01AG079149 and contract 75N92021D00001. Zhang reviews funding from R01AG079149 and residual class settlement funds within the matter of April Krueger vs. Wyeth, Inc., Case No. 03-cv-2496 (US District Courtroom, SD of California). McEvoy reviews funding from R01AG079149. All different authors declare no competing pursuits.
