Mild cognitive impairment is associated with issues in blood vessel function within the temporal lobes of the brain — the area responsible for memory — as indicated by a recent study. This research reveals that microvascular problems may serve as an early indicator of dementia and could also be a target for treatment.
Recent research led by USC shows that mild cognitive impairment is associated with blood vessel issues in the temporal lobes, which are crucial for memory.
The study findings were observed in participants both with and without amyloid accumulation in their brains, suggesting that problems with small blood vessels could be significant early markers of dementia and potential therapeutic targets.
The research involved scientists from various universities and was published in the journal Neurology.
“We are examining how well these small vessels respond to stimuli and their ability to widen. We have identified dysfunction in individuals experiencing memory difficulties,” stated senior author Daniel Nation, a gerontology and medicine professor at the USC Leonard Davis School of Gerontology. “This indicates that blood vessel dysfunction might occur very early in memory loss. This condition was present regardless of whether individuals displayed signs of Alzheimer’s pathology, indicating that those with memory problems still faced blood vessel issues.”
A New Indicator for Dementia
For this study, researchers engaged 144 older adults living independently in the community. Participants underwent neuropsychological evaluations, provided blood samples, and had brain MRI scans.
During the MRI scans, volunteers followed a breathing exercise that involved holding their breath for 15 seconds. This helped stimulate the dilation of blood vessels in the brain, a natural response known as “cerebrovascular reactivity,” which is essential for maintaining oxygen levels in the brain.
The focus was on the blood vessels that supply the temporal lobes, located on either side of the head, close to the ears. It was found that those whose blood vessels did not dilate properly demonstrated cognitive impairment.
“This approach allows us to identify the issues related to the blood vessels and their dilation abilities, which is not how many typically conceive of memory impairment in the elderly,” said Nation. “There is a growing understanding that dementia is often not solely tied to Alzheimer’s disease, but rather mixed pathology. Concentrating only on amyloid will not provide a complete picture, and this technique might be beneficial to include in our diagnostic strategies.”
“Our results highlight the importance of vascular health as a crucial component in memory decline,” noted first author Arunima Kapoor, a graduate student at the University of California, Irvine.
According to Nation, some medications for blood pressure might help maintain vascular function, thereby supporting memory preservation; however, further studies are necessary.
About This Study
Besides Nation and Kapoor, the research team also included John Paul Alitin, Trevor Lohman, Isabel Sible, Anisa Marshall, Aimee Gaubert, Xingfeng Shao, and Danny Wang, all from USC; Shubir Dutt from the University of California, San Francisco; and Allison Engstrom, Fatemah Shenasa, Lorena Sordo, and Elizabeth Head from the University of California, Irvine; along with David Robert Bradford and Kathleen Rodgers from the University of Arizona.
This research received funding from several National Institutes of Health grants—R01AG064228, R01AG060049, R01AG082073, P01AG052350, P30AG066530—and a grant from the American Heart Association, 23PRE1014192.
