Exaggerated Ambulatory Blood Pressure Variability Is Associated with Cognitive Dysfunction in the Very Elderly and Quality of Life in the Younger Elderly

BACKGROUND: It is reported that blood pressure (BP) variability increases with aging, and cognitive dysfunction may be related to BP variability; however, there are no data showing that exaggerated BP variability is associated with cognitive dysfunction or quality of life (QOL) in the older elderly. We investigated the relationships and the differences between ambulatory BP variability and cognitive function or QOL in younger elderly and very elderly. METHODS: We recruited both 101 very elderly (aged > or =80 years) and 101 younger elderly (aged 61 to 79 years). Twenty-four-hour ambulatory blood pressure monitoring, mini-mental state examinations (MMSE), and Medical Outcome Study Short-Form 36 Items Health Survey (SF-36) were performed for all subjects. RESULTS: The mean standard deviation (SD) of daytime systolic BP in young elderly was 17.2 +/- 4.6 mm Hg (mean SD +/- SD of mean SD), and that in very elderly was 21.2 +/- 4.3 mm Hg. The MMSE score significantly decreased with the tertile of SD of daytime systolic BP in very elderly (P = .004) and young elderly (P = .03). In very elderly, there was no significant association between the SD of daytime systolic BP and each of eight SF-36 categories. On the other hand, in younger elderly, two of eight SF-36 categories decreased with the tertile of SD of daytime systolic BP (P = .001 for Vitality and P = .003 for Role emotion). CONCLUSIONS: Very elderly had larger BP variability than younger elderly. Exaggerated ambulatory BP variability was related to cognitive dysfunction in the elderly, especially in the very elderly, and was related to lower QOL in the younger elderly.