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Lower Cardiac Index Levels and Cerebral Blood Flow

Neurology; ePub 2017 Nov 8; Jefferson, Liu, et al

Among older adults without stroke, dementia, or heart failure, systemic blood flow correlates with cerebral blood flow (CBF) in the temporal lobe, independently of prevalent cardiovascular disease (CVD), but not cardiovascular reactivity (CVR), according to a recent study. Vanderbilt Memory & Aging Project participants free of stroke, dementia, and heart failure were studied (n=314, age 73 ± 7 years, 59% male, 39% with mild cognitive impairment). Linear regressions with ordinary least-square estimates related cardiac index to regional CBF, with adjustment for age, education, race/ethnicity, Framingham Stroke Risk Profile score (systolic blood pressure, antihypertensive medication use, diabetes mellitus, current cigarette smoking, left ventricular hypertrophy, prevalent CVD, atrial fibrillation), APOE ε4 status, cognitive diagnosis, and regional tissue volume. Researchers found:

  • Lower cardiac index corresponded to lower resting CBF in the left and right temporal lobes.
  • Results were similar when participants with prevalent CVD and atrial fibrillation were excluded.
  • Cardiac index was unrelated to CBF in other regions assessed and CVR in all regions.

Jefferson AL, Liu D, Gupta DK, et al. Lower cardiac index levels relate to lower cerebral blood flow in older adults. [Published online ahead of print November 8, 2017]. Neurology. doi:10.1212/WNL.0000000000004707.