Cortical gray matter is thinner in people who develop dementia—and it appears to be an accurate biomarker seen five to 10 years before any symptoms.
Researchers from the UT Health San Antonio, UC Davis, and Boston University made the discovery after conducting MRI scans on a large cohort of volunteers. The results are published in Alzheimer’s & Dementia. [1]
For the study, 1,000 people from Massachusetts and 500 from California participated, with both groups averaging an age of 70 to 74 when the MRI scans were collected. The group from Massachusetts were participants in the Framingham Heart Study, a multigenerational investigation that provided detailed medical records of the cohort, allowing researchers to compare MR images from those with dementia and those without.
“We went back and examined the brain MRIs done 10 years earlier, and then we mixed them up to see if we could discern a pattern that reliably distinguished those who later developed dementia from those who did not,” study co-author Sudha Seshadri, MD, at UT Health San Antonio said in a statement. Seshadri is also a senior investigator on the Framingham Heart Study.
“This kind of study is only possible when you have longitudinal follow-up over many years as we did at Framingham and as we are building in San Antonio,” she added. “The people who had the research MRI scans while they were well and kept coming back to be studied are the selfless heroes who make such valuable discoveries, such prediction tools possible.”
Consistent results were observed across populations, indicating that thicker ribbons of cortical gray matter were associated with a reduced likelihood of developing dementia symptoms, while thinner ribbons correlated with an increased risk of symptoms emerging within five to 10 years, and poorer overall dementia outcomes.
“The big interest in this paper is that, if we can replicate it in additional samples, cortical gray matter thickness will be a marker we can use to identify people at high risk of dementia,” study lead author Claudia Satizabal, PhD, of UT Health San Antonio said in the same statement. “By detecting the disease early, we are in a better time window for therapeutic interventions and lifestyle modifications, and to do better tracking of brain health to decrease individuals’ progression to dementia.”
The relationship between the thinning ribbon of gray matter and dementia risk behaved the same way in different races and ethnic groups. While more research is necessary, the study authors believe the thickness of cortical gray matter could be used to gauge dementia risk for patients in the future once it’s measured in different age groups to establish an average.
Read the full study at the link below.
Chad is an award-winning writer and editor with over 15 years of experience working in media. He has a decade-long professional background in healthcare, working as a writer and in public relations.