Blood pressure variability and dementia rating scale performance in older adults with cardiovascular disease

Objective: The present study examined the relationship between multiple indices of blood pressure (13P) and cognitive function (as measured by the Dementia Rating Scale). Background: Cardiovascular disease (CVD) is associated with cognitive dysfunction and cerebrovascular pathology in the elderly and is a known risk factor for stroke and Alzheimer disease. Yet, the mechanisms for the effects of CVD on cognitive function are not well understood. Methods: Participants were 97 nondemented older adults with CVD who underwent neuropsychologic assessment, and a 2-hour cardiovascular laboratory protocol. Results: After controlling for age and years of education, results of hierarchical linear regression analyses indicate a significant positive relationship between a function of BP variability (SD of systolic BP divided by the average diastolic BP) and cognitive function (R-2 change = 0.042, F (1, 85) = 5.434, P < 0.05). No relationship emerged between any other BP index and cognitive function. Conclusions: Contrary to expectations, greater BP variability was associated with better, not poorer, cognitive test performance. These findings suggest that the relationship between BP and cognitive function is more complicated than originally conceptualized and requires further investigation.