The age‐related reduction in cerebral blood flow affects vertebral artery more than internal carotid artery blood flow

Abstract

Summary Ageing reduces cerebral blood flow (CBF), while mean arterial pressure (MAP) becomes elevated. According to ‘the selfish brain’ hypothesis of hypertension, a reduction in vertebral artery blood flow (VA) leads to increased sympathetic activity and thus increases MAP. In twenty‐two young (24 ± 3 years; mean ± SD) and eleven elderly (70 ± 5 years) normotensive men, duplex ultrasound evaluated whether the age‐related reduction in CBF affects VA more than internal carotid artery (ICA) blood flow. Pulse‐contour analysis evaluated MAP while near‐infrared spectroscopy determined frontal lobe oxygenation and transcranial Doppler middle cerebral artery mean blood velocity (MCA Vmean). During supine rest, MAP (90 ± 13 versus 78 ± 9 mmHg; P<0·001) was elevated in the older subjects while their frontal lobe oxygenation (68 ± 7% versus 77 ± 7%; P<0·001), MCA Vmean (49 ± 9 versus 60 ± 12 cm s−1; P = 0·016) and CBF (754 ± 112 versus 900 ± 144 ml min−1; P = 0·004) were low reflected in VA (138 ± 48 versus 219 ± 50 ml min−1; P<0·001) rather than in ICA flow (616 ± 96 versus 680 ± 120 ml min−1; P = 0·099). In conclusion, blood supply to the brain and its oxygenation are affected by ageing and the age‐related decline in VA flow appears to be four times as large as that in ICA and could be important for the age‐related increase in MAP.

The relationships between age, sex, and cerebrovascular reactivity to hypercapnia using traditional and kinetic-based analyses in healthy adults

“…Despite observing a negative relationship between MCAv and age, baseline ICA mean blood flow showed no relationship with advancing age. This is in line with previous findings ( 66 – 68 ). It is proposed that declines in the posterior circulation with advancing age are more marked compared with the anterior circulation ( 68 , 69 ).…”

“…This is in line with previous findings ( 66 – 68 ). It is proposed that declines in the posterior circulation with advancing age are more marked compared with the anterior circulation ( 68 , 69 ). A potential explanation for the preserved mean ICA blood flow response may be due to the high physical activity levels in the current sample (∼2,182 METmin/wk), with regular physical activity shown to attenuate the age-related decline in CBF ( 70 , 71 ) and endurance exercise training shown to increase CBF and CVR responses ( 72 ).…”

Linking the Meso and Macroscale Determinants of Cerebral Ageing

“…Older adults also often show decreased blood flow, caused by arterial stiffness, luminal narrowing and microvascular rarefaction. Changes in blood vessel permeability in age is caused by changes in arterial stiffness, endothelial senescence and injury to vessel walls over time (Farrall & Wardlaw, 2009;Olesen et al, 2019;Pinto, 2007).…”

Effects of Massage on Neuro-Vascular Regulation and Apoptosis in Rabbits with Cervical Spondylosis of the Vertebral Artery Type

“…Some studies have shown that there are many sympathetic nerve bers distributed on the ligamentum avum (LF), which may be the anatomical basis for the development of cervical vertigo [3]. A large body of literature con rmed that sympathetic nerves were closely associated with inadequate blood supply to the vertebral arteries [4][5][6]. Our previous ndings [7] also indicated that two sympathetic neurotransmitters, neuropeptide Y (NPY) and endothelin-1 (ET-1), are closely related to changes in vertebral artery blood ow.…”