Emerging MRI and PET Research Reveals Link Between Visceral Abdominal Fat and Early Signs of Alzheimer's Disease

A higher amount of visceral abdominal fat in one’s midlife years may be an early warning sign for the development of Alzheimer’s disease, according to magnetic resonance imaging (MRI) and positron emission tomography (PET) findings recently presented at the Radiological Society of North America (RSNA) conference.

In a cohort of 54 cognitively healthy people with an average body mass index (BMI) of 32, researchers found that a higher amyloid PET tracer uptake in the precuneus cortex, a brain region known to show early pathological sings of Alzheimer’s disease, was associated with a higher ratio of visceral abdominal fat to subcutaneous fat.

“Showing this association in midlife in individuals with obesity highlights that we are observing early amyloid pathology in the Alzheimer’s (disease) signature areas 20 years before the onset of Alzheimer’s disease,” noted Mahsa Dolatshahi, M.D., M.P.H., the lead author of the study and a postdoctoral research scholar affiliated with the Mallinckrodt Institute of Radiology at Washington University, in a recent video interview.

(Editor’s note: For related content, see “Emerging Neuroradiology Concepts: Could Tau-PET be a New Standard in Assessing Possible Alzheimer’s Disease?,” “FDA Clears AI-Powered MRI Software for Brain Atrophy,” and “Brain PET Study Suggests Link Between Early Amyloid Accumulation and Repetitive Subconcussive Trauma.”)

Cyrus A. Raji, M.D., Ph.D, said the long relied upon body mass index (BMI) is an “imperfect measure” for characterizing body fat. In taking a closer look at the anatomically specific distribution of visceral fat and subcutaneous fat and its relationship to the risk of developing Alzheimer’s disease, Dr. Raji noted the preliminary research findings have many potential implications for early intervention.

“By characterizing the actual distribution of fat and the biophysical profiles, we can really start building an idea of who needs a more aggressive form of lifestyle intervention or related drug therapies,” explained Dr. Raji, an associate professor of radiology and neurology at the Mallinckrodt Institute of Radiology at Washington University.

“This will not only decrease the risk for Alzheimer’s disease for people at midlife, but it will also improve the potential for people to be more successful on any Alzheimer’s drug they may have to take later in life since individuals who take those drugs are less likely to benefit from those drugs if their underlying brain health is already impaired.”

For additional insights from Drs. Dolatshahi and Raji, watch the video below.