Abstract
Background: Past studies link elevated blood pressure (BP) and BP variability to adverse neurocognitive changes in community samples. However, little is known about the relationship between BP indices and cognitive function in older CVD patients. Methods: A total of 99 older adults with CVD completed a comprehensive neuropsychological test battery. Resting BP measurements were collected every 10 min for 2 hr during a separate cardiac assessment. Five BP indices were generated: average and standard deviation of systolic blood pressure (SBP), average and standard deviation of diastolic blood pressure (DBP), and a function of systolic variability and average diastolic pressure. We examined the relationship between these BP indices and cognitive function. Results: Partial correlation adjusting for age and education revealed that the function of systolic variability and average diastolic pressure (SBP standard deviation divided by the average DBP) was most closely related to test performance, showing significant associations to both Learning/Memory (r = 0.25) and Language functioning (r = 0.22). SBP indices were also related to Language functioning (SBP avg., r = 0.22; SBP SD, r = 0.25), though DBP indices were unrelated to performance in any cognitive domain. Conclusions: The current findings indicate that BP is modestly related to cognitive function in older CVD patients. Contrary to expectations, greater BP variability was associated with better, not poorer, cognitive test performance. Such findings suggest that the relationship between BP and cognitive function is more complicated than typically believed and requires further examination.