Ankle brachial index and cognitive function among elderly hypertensive patients with different age stratification: a 2-year longitudinal study

BackgroundThe ankle brachial index (ABI) is widely used to evaluated peripheral artery disease and atherosclerosis. This study was designed to evaluate the association between the ABI and cognitive function in elderly hypertensive patients stratified by age. MethodsA total of 408 elderly hypertensive patients from two hospitals were included, and followed up for two years. Cognitive function was assessed by the Mini-Mental State Examination (MMSE). Multivariate logistic regression analysis was employed to evaluate the association between ABI and cognitive impairment, and the analysis of covariance (ANCOVA) was used to compare the cognitive decline according to the ABI during 2-year follow-up in different age groups adjusted for related confounding factors.ResultsThe ABI was independently associated with cognitive impairment in overall and old elderly (75 ~ 89 years old) hypertensive patients (all P < 0.05), but not in the young elderly (60 ~ 75 years old) (P = 0.113). During ANCOVA, the MMSE score decline value of the low ABI group was greater than that of the high ABI group (0.767 vs 0.244; F = 5.845, P = 0.016) over 2-year follow-up. There was a significant difference of MMSE score decline value between the young and old elderly (0.345 vs 1.005; F = 4.728, P = 0.031) in Low ABI group, but no significant difference was found in High ABI group (P = 0.235). ConclusionsThe ABI was associated with cognitive impairment and cognitive function decline in elderly hypertensive patients, especially in the old elderly. Early monitoring of the ABI and initiation of individualized anti-atherosclerotic therapy might help prevent cognitive impairment in elderly hypertensive patients more effectively.