Researchers studying Alzheimer’s disease have created an approach to classify patients with Alzheimer’s disease, a finding that may open the door for personalized treatments.
“Alzheimer’s, like breast cancer, is not one disease,” said lead author Shubhabrata Mukherjee, research assistant professor in general internal medicine at the University of Washington School of Medicine. “I think a good drug might fail in a clinical trial because not all the subjects have the same kind of Alzheimer’s.
This study, published in the recent issue of Molecular Psychiatry, involves 19 researchers from several institutions, including Boston University School of Medicine, the VA Puget Sound Health Care System and Indiana University School of Medicine.
The researchers put 4,050 people with late-onset Alzheimer’s disease into six groups based on their cognitive functioning at the time of diagnosis and then used genetic data to find biological differences across these groups.
“The implications are exciting,” said corresponding author Paul Crane, professor of general internal medicine at the University of Washington School of Medicine. “We have found substantial biological differences among cognitively defined subgroups of Alzheimer’s patients.”
Identification of cognitive subgroups related to genetic differences is an important step toward developing a precision medicine approach for Alzheimer’s disease.
The participants received cognitive scores in four domains: memory, executive functioning, language, and visuospatial functioning.
The largest group (39%) had scores in all four domains that were fairly close to each other. The next largest group (27%) had memory scores substantially lower than their other scores. Smaller groups had language scores substantially lower than their other scores (13%), visuospatial functioning scores substantially lower than their other scores (12%), and executive functioning scores substantially lower than their other scores (3%). There were 6% who had two domains that were substantially lower than their other scores.
The participants came from five studies, and it took more than two years to standardize the neuropsychological test scores across all the studies in order to detect meaningful patterns. The mean age was 80, 92 percent self-reported white race, and 61 percent were female.