Researchers say that a special digital imaging technique can spot the tau protein and predict cognitive decline in people with Alzheimer’s disease better than traditional imaging methods.
Doctors typically use positron emission tomography (PET) as one of the tools to diagnose Alzheimer’s disease. Their imaging technique spots tau tangles, a protein found in the brains of people with the disease. A study published in Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association urges medical professionals to adopt tau PET to improve care.
In addition to tau tangles, people with Alzheimer’s have amyloid plaques in their brains. The plaques aren’t necessarily accompanied by cognitive or memory loss while tau is correlated strongly to clinical symptoms. The disease develops silently over decades, and many people can’t intervene until they have symptoms. It’s harder to find imaging techniques to spot tau, specifically.
When someone has a PET scan, the healthcare professional injects them with a low-level radioactive tracer that fades away within a few hours. The tracer binds to molecules that doctors are looking for, so they can see them on the PET scan, said Valentina Garibotto, MD, an associate professor in the Department of Radiology and Medical Informatics at University of Geneva.
Along with researchers from Geneva University Hospitals, the team looked at different kinds of PET scans to see which could best spot the proteins linked to the disease.
“Our results show that while the various PET measures were all associated with the presence of cognitive symptoms, confirming their role as strong indicators of Alzheimer’s disease, tau PET was the best to predict the rate of cognitive decline, even in individuals with minimal symptoms,” said Cecilia Boccalini, a PhD student and first author of the study.
Researchers used flortaucipir, a radiotracer that binds to the tau protein so doctors can see it. They took scans on about 90 people in the medical center’s memory care center.
“This breakthrough is crucial for better management of Alzheimer’s disease,” Garibotto said. “Recently, drugs targeting amyloid have shown positive results. New drugs targeting the tau protein also look promising. By detecting the pathology as early as possible, before the brain is further damaged, and thanks to new treatments, we hope to be able to make a greater impact on patients’ future and quality of life.”
