P3‐397: Increase in cerebrovascular resistance and reduction in cerebral blood flow in patients with mild cognitive impairment
Year: 2012
Type: article
Study design: Observational Study
Abstract: Brain hypoperfusion occurs in Alzheimer's disease (AD), reflecting neuronal degenerative changes and/or vascular abnormalities. However, it is not known by how long these abnormalities are present before clinical appearance of the disease. In this study, we tested the hypothesis that reduction in brain perfusion can be detected using color duplex Doppler ultrosonography in patients with mild cognitive impairment (MCI). Twenty-eight patients with amnestic MCI (14 females, 67 ± 7 yr BMI: 24 ± 4kg/m 2) and 30 age and educational level matched normal control subjects (16 females, 67± 7 yr, BMI: 23± 4 kg/m 2) participated in this study. Global and regional cerebral blood flow (CBF) were measured under supine resting conditions using color duplex Doppler ultrasonography in the left and right internal carotid (ICA) and vertebral arteries (VA), respectively. Volumetric blood flow (BF) was calculated by multiplying the time averaged blood flow velocity of 5 cardiac cycles with the cross-sectional area of the arteries. Global CBF was calculated as a sum of the left and right ICA and VA BF. Cerebrovascular resistance (CVR) indexes were calculated as mean blood pressure (MBP) divided by the global, ICA, and VA BF, respectively. Baseline MBP was similar between the MCI and normal controls (90 ± 9 mmHg vs. 86 ± 11 mmHg, P = 0.19). However, both the global and ICA BF were reduced by 11% in the MCI when compared to the controls (587± 99 vs. 659± 128 ml/min, P = 0.03 and 444± 87 vs. 499± 110 ml/min, P = 0.05). Associated with reduction in CBF, global and ICA CVR were increased significantly in the MCI relative to the controls (0.16 ± 0.03 vs. 0.13 ± 0.13mmHg·min/ml, P = 0.005 and 0.21± 0.05 vs. 0.18± 0.05mmHg·min/ml, P = 0.03). The global and internal carotid blood flow reduced in patients with MCI are detectable using color duplex Doppler ultrosonography. Moreover, increases in cerebrovascular resistance in MCI subjects suggest the presence of vascular abnormalities at the pre-dementia stage of AD.
Source: Alzheimer s & Dementia
Language: English
Subfield: Psychiatry and Mental health
Field: Medicine
Domain: Health Sciences
Open Access status: bronze
OpenAlex ID: W2122165230