Blood test may detect dementia risk a decade before symptoms appear

Research shared at the 2026 Alzheimer’s Association International Conference demonstrated positive developments for a blood test that can predict increased risk of dementia up to 10 years before initial symptoms surface.

I’ve long followed the research developments when it comes to blood tests for Alzheimer’s because I believe it could help people get diagnosed earlier, where current approved treatments have the best chance of slowing down the disease. We need a simple, minimally-invasive method to detect cognitive changes as early as possible, and the blood biomarker p-tau217 may play a critical role.

According to researchers, study participants with the highest levels of the blood biomarker p-tau217 had an approximately 78% risk of developing cognitive impairment over a 10-year period. P-tau217 is associated with tau tangles in the brain and with levels of beta amyloid, both which are Alzheimer’s hallmarks, according to the Alzheimer’s Association. The full study is published on JAMA.

Elevated levels of protein can exist in a person’s brain with no noticeable memory or thinking problems. It’s important to note that some people have high levels of tau and don’t develop cognitive issues. Still, the results of this study are promising in adding an accessible tool to what can be a frustrating diagnostic process.

While there will be a debate on the value of predictive data for a disease with no cure, a study I reported on earlier this year found that people overwhelmingly support such tests being available. I have always been firmly in the camp of wanting to know what my Alzheimer’s risk is because it runs so rampant in my family. That’s why I’ve done genetic testing, which found I have a copy of the APOE4 gene. If the p-tau217 becomes available to the public, I would seek it out.

If my brain were filled with tau tangles would I drastically change my life? I’m not sure, but we do know that lifestyle changes can have a positive impact on reducing dementia risk. I also think such a finding would prompt me to legally finalize my plans (medical power of attorney, etc.) if I should become cognitively impaired. If test results suggested I was at a much greater risk of developing dementia over the next 10 years, I probably would shift priorities to ensure that any projects that require my full brain power, such as writing another book, get done sooner, rather than later. The same with travel or any other bucket list goals.

I’ve followed Alzheimer’s research closely for about 20 years now, and over the next 20 years, my risk of developing this disease will increase. The current state of research seems to be more on a trajectory of disease management, than a cure. Early testing, lifestyle changes, and better treatments will all play critical roles for how my generation will navigate Alzheimer’s and other dementias.

Final call: I’m participating in the Smashwords July Summer/Winter sale. Get my books, including the award-winning The Reluctant Caregiver, for half-off the normal price. The sale runs through July 31.