A single blood marker could quietly sign dementia danger a long time upfront.
Scientists on the College of California, San Diego, have recognized a blood sign that would forecast dementia danger a long time earlier than signs start. Their examine, lately printed in JAMA Community Open, highlights a protein known as phosphorylated tau 217 (p-tau217), which displays early adjustments within the mind linked to Alzheimer’s illness.
Amongst older girls with no indicators of cognitive decline initially of the examine, these with greater ranges of p-tau217 have been much more prone to develop delicate cognitive impairment or dementia years later. In some instances, the sign appeared as much as 25 years earlier than prognosis, suggesting that the illness course of could start silently a lot sooner than beforehand understood.
“Our examine suggests we could possibly establish girls at elevated danger for dementia a long time earlier than signs emerge,” mentioned Aladdin H. Shadyab, PhD, MPH, first creator of the examine and UC San Diego affiliate professor of public well being and drugs on the Herbert Wertheim Faculty of Public Well being and Human Longevity Science and the Faculty of Drugs. “That sort of lengthy lead time opens the door to earlier prevention methods and extra focused monitoring, slightly than ready till reminiscence issues are already affecting every day life.”
Lengthy-Time period Examine Reveals Predictive Biomarker
The evaluation included 2,766 members from the Girls’s Well being Initiative Reminiscence Examine, a nationwide venture that enrolled girls ages 65 to 79 within the late Nineties and adopted them for so long as 25 years. All members had regular cognitive operate at enrollment.
Researchers later examined saved blood samples to measure p-tau217, which displays early Alzheimer’s-related adjustments within the mind. Over time, they recognized members who developed reminiscence or pondering issues, together with dementia.
Girls with greater p-tau217 ranges initially of the examine have been considerably extra prone to develop dementia later in life. Danger rose steadily alongside biomarker ranges, with the very best ranges similar to the best probability of long-term cognitive decline.
The power of this hyperlink was not uniform throughout all members. Greater p-tau217 ranges have been extra strongly tied to worse cognitive outcomes in girls over age 70 in comparison with those that have 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 have 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,” mentioned Linda Okay. McEvoy, PhD, senior creator 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 vital for accelerating analysis into the components that have an effect on danger of dementia and for evaluating methods which will scale back danger.”
At current, blood-based biomarkers should not advisable for medical use in individuals with out signs of cognitive impairment. The researchers emphasize that extra research are wanted to find out how p-tau217 testing may very well 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 circumstances work together with plasma p-tau217 over time to affect dementia danger.
“Finally, the aim is not only prediction,” Shadyab added, “however utilizing that data to delay or stop dementia altogether.”
Reference: “Plasma Phosphorylated Tau 217 and Incident Gentle 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 studies funding from R01AG079149. Mielke studies 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; cost from Roche, Novo Nordisk, Biogen, and Medscape; and funds for grant opinions. Resnick studies employment by the NIA Intramural Analysis Program in the course of the examine; help from the McKnight Basis Annual Assembly as a keynote speaker; ISAB member of the Canadian Consortium on Neurodegeneration in Growing older; Exterior Advisory Board Member on the Grownup Growing older Mind Connectome Examine; and ISAB member for Dementia Platforms UK. Ngyuen studies funding from 5K99AG082863-02. LaCroix studies funding from grant R01AG079149 and contract 75N92021D00001. Zhang studies funding from R01AG079149 and residual class settlement funds within the matter of April Krueger vs. Wyeth, Inc., Case No. 03-cv-2496 (US District Court docket, SD of California). McEvoy studies funding from R01AG079149. All different authors declare no competing pursuits.
