HealthDay News — Among older adults, lower cardiac index is associated with lower resting cerebral blood flow (CBF) in the temporal lobes regardless of cardiovascular disease (CVD) but is not associated with cerebrovascular reactivity (CVR), according to a study published online in Neurology.
Angela L. Jefferson, PhD, from the Vanderbilt Memory & Alzheimer’s Center in Nashville, Tennessee, and colleagues studied 314 Vanderbilt Memory & Aging Project participants (aged 73±7 years) free of stroke, dementia, and heart failure. The authors examined the correlation between cardiac index and resting CBF and CVR.
The researchers found that there was a correlation for lower cardiac index with lower resting CBF in the left and right temporal lobes.
When participants with prevalent CVD and atrial fibrillation were excluded, the results were similar. There was no correlation for cardiac index with CBF in other regions or with CVR in all regions. In secondary cardiac index × cognitive diagnosis interaction models, only in cognitively normal participants were cardiac index and CBF associations present, and these affected a majority of regions assessed, with strongest effects in the left and right temporal lobes.
“Among older adults without stroke, dementia, or heart failure, systemic blood flow correlates with cerebral CBF in the temporal lobe, independently of prevalent CVD, but not CVR,” the authors write.
Jefferson AL, Liu D, Gupta DK, et al. Lower cardiac index levels relate to lower cerebral blood flow in older adults [published online November 8, 2017]. Neurology. doi: 10.1212/WNL.0000000000004707