Association between central blood pressure, arterial stiffness and low cognitive scores in South African adults

BackgroundThe burden of hypertension in South Africa, as well as the successive cardiovascular morbidity and mortality is increasing. Hypertension presents a risk for subsequent cognitive impairment with age. This study sought to determine the association between blood pressure, arterial stiffness, using pulse wave velocity and pulse amplification pressure, and cognitive function in younger and older adults from a 30yr old urban South African birth cohort study. MethodsWe conducted a cross-sectional study among n=93 index children (now age 29yr) and their mothers (all women). We collected peripheral and central blood pressure (BP) variables, and conducted a cognitive assessment using the Montreal Cognitive Assessment (MoCA) instrument and analysed the association of BP variables with global cognitive tests and specific domains. ResultsForty percent of the pooled sample had low MoCA total scores, and 32% of the total sample had hypertension. No associations were found in the regression analysis between BP related variables and total MoCA scores. Also, no associations were found between peripheral and central BP variables with individual cognitive domains when stratified by age. A significant relationship was found between mean pressure and low visual perception (i.e. the ability to interpret information that is seen and give it meaning; p=0.02). ConclusionCentral mean pressure is associated with low visual perception domain among black women. These findings add to the growing evidence which suggests that central BP variables are important to explore as exposure proxies for studying the association of BP and cognitive decline especially at mid-life.