A team led by Dr. Shao-Yuan Chuang from the Institute of Population Sciences investigated the association between carotid flow velocity, cognitive function, and blood pressure (BP) in a community-based population. A total of 1,684 elders aged more than 50 years without dementia were recruited from the I-Lan Longitudinal Aging Study and underwent measurements of BP and biochemical markers. Mini-Mental State Examination (MMSE) and comprehensive neuropsychological tests were used to evaluate cognitive function. Peak systolic velocity (PSV) and end-diastolic velocity (EDV) were measured in common and internal carotid artery. Multivariable linear and logistic regression were used to evaluate the relationship of cognitive function with carotid flow velocities and BP.
The team found carotid flow velocities (PSV: standardized β = 0.067, P = 0.0009; and EDV: standardized β = 0.067, P = 0.0021) and systolic blood pressure (standardized β = −0.061, P = 0.005) were positively and negatively associated with MMSE, respectively, in the model with adjustments for age, sex, educational attainment, nutritional status, and smoking. Similar trends were noted for the associations between flow velocities and different neuropsychological tests.
The team demonstrated that both low carotid flow velocity and high BP were related to cognitive decline and confirmed that older age, female sex, low education, and malnutrition are all positively associated with impaired cognitive function, as demonstrated in other previous studies. As such, reduced cerebral flow velocity plays a role in the pathophysiology of cognitive function impairment and may reflect increased intracranial arterial resistance. This finding has been published in American Journal of Hypertension (2019 Mar;32(3):289-297).
Citation: Chuang, SY; Cheng, HM; Mitchell, GF; Sung, SH; Chen, CH; Pan, WH; Hwang, AC; Chen, LK; Wang, PN. Carotid flow velocities and blood pressures are independently associated with cognitive function. American Journal of Hypertension. 2019 Mar;32(3):289-297.