Cardiovascular fat volume may impact cognitive function among postmenopausal women
As the cardiovascular profiles of women deteriorate after menopause, they may see a greater risk for dementia, according to a study presented during the North American Menopause Society Annual Meeting.
Researchers at the University of Pittsburgh identified a link between cardiovascular fat volume and radiodensity and cognitive function. They also uncovered racial differences in this association.
Cardiovascular fat deposition, which the researchers called a novel risk factor for cardiovascular disease, is higher in postmenopausal women than in premenopausal women. It also is believed to affect cognitive function through neuropathological pathways by changing the secretion of inflammatory cytokines and adipokines. Radiodensity characterizes the quality of cardiovascular fat.
“Heart and brain diseases share common risk factors across the life course. Cardiovascular fat, which is the fat surrounding the heart and vasculature, could be one of those shared risk factors,” author Samar R. El Khoudary, PhD, MPH, BPharm, FAHA, an associate professor of epidemiology at the University of Pittsburgh Graduate School of Public Health, told Healio.
When fat depots around the heart and vasculature secrete adipokines and inflammatory markers directly to the vasculature and myocardium, subclinical changes that can predict heart diseases and cognitive decline may result, El Khoudary said.
“Women transitioning through menopause have greater cardiovascular fat volumes compared with before menopause. The quantity as well as the quality of cardiovascular fat depots as measured by radiodensity Hounsfield units from CT scans have been linked to risk for subclinical vascular diseases,” she said.
Women begin experiencing changes in their cognitive function during midlife, El Khoudary continued, and the quantity or quality of cardiovascular fat depots also may be related to the status of cognitive function in women.
The researchers used data from the Study of Women’s Health Across the Nation to assess the associations of cardiovascular fat volume and radiodensity with future cognitive performance among midlife women.
The volume and radiodensity of cardiovascular fat, including epicardial adipose tissue, total heart adipose tissue and perivascular adipose tissue (PVAT) surrounding the descending aorta, were measured through CT scans.
The researchers assessed the women’s cognitive performance using a battery of tests —working memory via the Digit Span Backwards Task, immediate and delayed recall of verbal episodic memory via the East Boston Memory Test, and processing speed via the Symbol Digit Modalities Test.
Also, the researchers evaluated the racial differences in these associations because Black individuals paradoxically have lower cardiovascular fat volume but are at a higher risk for heart disease and have a higher prevalence of Alzheimer’s disease than white individuals.
According to the researchers, 30.6% of the 487 women in the study were postmenopausal, and 35.9% were Black (mean age at CT, 50.9 years [standard deviation = 2.9]). The results revealed a significant association between a higher PVAT radiodensity and worse performance in working memory, the researchers said.
“The reported associations were independent of volume of PVAT depot as well as waist circumference and other known confounders,” El Khoudary said.
The study also found a significant interaction between PVAT radiodensity and race, with a higher baseline PVAT radiodensity at midlife associated with lower future performance in verbal episodic memory among Black women but not white women, the researchers said.
“The reported racial and ethnic differences in this preliminary work should be viewed with caution given the multiple tests we have performed since this was an exploratory analysis,” El Khoudary said. “A follow-up analysis is ongoing and will better enable us to understand if the reported interaction was a discovery by chance.”
According to the researchers, their findings suggest that the quality, not the quantity, of PVAT at midlife may serve as a novel biomarker of the status of cognitive function among women later in life.
“We need more research to understand the underlaying mechanisms of the reported association and what makes this fat depot very specific to working memory function in women,” El Khoudary said. “Other studies should replicate our findings. We need more research on why only PVAT showed such an association and what it is about the quality of this fat that may be linked to working memory function.”
Qi M, et al. Abstract S-11. Presented at: North American Menopause Society Annual Meeting; Sept. 22-25, 2021; Washington, D.C.