Nasal swab test spots early Alzheimer’s signals

Alzheimer’s disease affects millions of people worldwide, yet the illness is hardest to catch at the very beginning, when new treatments may work best. In a new study, Duke Health researchers show that a quick, outpatient nasal swab can pick up early biological changes linked to Alzheimer’s, even before thinking and memory problems appear.

The study, published in Nature Communications, used a gentle swab placed high inside the nose to collect nerve and immune cells. When researchers analyzed these cells, they found clear patterns that separated people with early or diagnosed Alzheimer’s from those without the disease.

“We want to be able to confirm Alzheimer’s very early, before damage has a chance to build up in the brain,” said Bradley J. Goldstein, M.D., Ph.D., corresponding author and professor in the departments of Head and Neck Surgery & Communication Sciences, Cell Biology and Neurobiology at Duke University School of Medicine.

“If we can diagnose people early enough, we might be able to start therapies that prevent them from ever developing clinical Alzheimer’s,” Goldstein said.

The procedure to collect nasal cells took just a few minutes. After applying a numbing spray, a clinician guides a tiny brush into the upper part of the nose where smell-detecting nerve cells live. Researchers then study the collected cells to see which genes are active, a sign of what’s happening inside the brain.

The study compared samples from 22 participants, measuring the activity of thousands of genes across hundreds of thousands of individual cells, amounting to millions of data points. The nasal swab was able to pick up early shifts in nerve and immune cells. This includes people who showed lab-based signs of Alzheimer’s but had no symptoms yet.

A combined nose tissue gene score correctly separated early and clinical Alzheimer’s from healthy controls about 81% of the time.

Mary Umstead, a voluntary participant in the study, said she felt moved to join the research in honor of her late sister, Mariah Umstead.

“When the opportunity came along to be part of a research study, I just jumped at it because I would never want any family to have to go through that kind of loss that we went through with Mariah,” Mary said. “I would never want any patient to go through what she went through either.”

Mary said Mariah was 57 years old when she was diagnosed with young-onset Alzheimer’s, but her family started noticing signs of the disease long before she was diagnosed.

Current blood tests for Alzheimer’s detect markers that appear later in the disease process. By contrast, this nasal swab captures living nerve and immune activity and may provide an earlier, more direct look at disease-related changes, helping identify people at risk sooner.

“Much of what we know about Alzheimer’s comes from autopsy tissue,” said Vincent M. D’Anniballe, the study’s first author and student in the Medical Scientist Training Program at Duke. “Now we can study living neural tissue, opening new possibilities for diagnosis and treatment.”

The Duke team, in collaboration with the Duke & UNC Alzheimer’s Disease Research Center, is now expanding the research to larger groups and exploring whether the swab could help track how well treatments are working over time. Duke has filed a U.S. patent related to this approach.