A 10 year study has shown that changes in certain key biomarkers during mid-life could identify patients with a high risk of someday developing dementia. Researchers from Washington University School of Medicine (MO, USA) gathered data from cognitively normal participants and completed a clinical, cognitive imaging and cerebrospinal fluid biomarker analysis at intervals to track changes in the group.
Their findings represent the first large data set to demonstrate that biomarkers shown by previous research to be affected by Alzheimer’s disease change over time during midlife. Anne Fagan, Professor of Neurology at the Washington University School of Medicine and senior author of the work, explained: “It’s too early to use these biomarkers to definitively predict whether individual patients will develop Alzheimer’s disease, but we’re working toward that goal. One day, we hope to use such measures to identify and treat people years before memory loss and other cognitive problems become apparent.”
The study gathered data from 169 individuals whose ages ranged from 45 to 75 and tracked their progress over 10 years. They underwent assessment every 3 years, and researchers found that diminishing levels of the biomarker amyloid beta 42 in cerebrospinal fluid in the 45 to 54 age group was linked to plaques in future brain scans. In addition, they observed a sharp increase in biomarkers of brain-cell injury such as tau as some participants reached their mid-50s to mid-70s. They also determined that the concentration of a newly recognized protein indicative of inflammation, YKL-40, increased across the age groups covered in the study.
The changes observed in the study were all more evident in participants who carried two copies of a particular variation of the gene APOE, a genotype known to dramatically increase an individual’s chance of developing Alzheimer’s disease.
Discussing the team’s ongoing work following study participants with and without a family history of dementia, Fagan concluded, “Alzheimer’s is a long-term process, and that means we have to observe people for a long time to catch glimpses of it in action.”