Blood Test Predicts Alzheimer's Up to 10 Years Early

Doctors can now identify people at high risk for Alzheimer's disease years before they show any symptoms, thanks to a remarkably accurate blood test that could change how we fight dementia.

Recent research presented at the Alzheimer's Association International Conference found that older adults with the highest levels of a protein called p-tau217 have a one in three chance of developing memory problems within five years. Within a decade, that risk jumps to 78 percent.

"Knowing you are at high risk of developing dementia up to a decade prior to even the first symptom showing up, that is changing the game for sure," said Ashton Houghton, executive director of the Alzheimer's Association South Carolina Chapter.

The test works by detecting abnormal proteins that build up in the brain before patients notice any changes. These toxic proteins form tangles inside brain cells, damaging them long before memory loss begins.

Another blood test called PrecivityAD2 showed equally promising results. When primary care doctors used this test on more than 1,300 patients in Sweden, they matched specialists in accurately diagnosing dementia about 90 percent of the time.

This matters especially in places like South Carolina, where dementia specialists are scarce and appointments can be hard to get. The blood tests allow family doctors to screen patients without lengthy waits or expensive specialist visits.

"There's never going to be enough specialists, never going to be enough neurologists," said Dr. Nicholas Milano, director of the South Carolina Alzheimer's Network at the Medical University of South Carolina. "This needs to be a partnership between primary care and neurology."

The timing couldn't be better. The FDA just approved a new version of Leqembi, an effective Alzheimer's treatment that can now be injected at home instead of requiring trips to an infusion center every two weeks.

For rural patients who previously faced hours of driving for treatment, this changes everything. The medication can be shipped directly to patients and administered at home, opening access to care for thousands who couldn't manage the travel.

The Ripple Effect

This breakthrough reaches far beyond individual patients. Early detection means families can plan ahead, making important decisions while their loved one can still participate.

It also means researchers can finally test potential treatments on people in the earliest stages of disease, when interventions might work best. Every successful early treatment brings us closer to preventing Alzheimer's altogether.

MUSC already offers remote consultations to help primary care doctors across the state confirm diagnoses, and these new tools will make that partnership even stronger.

The combination of early detection and accessible treatment represents the kind of progress that seemed impossible just a few years ago, bringing hope to the millions of families touched by Alzheimer's disease.