Variable Blood Pressure Tied to Worse Cognitive Functioning
(HealthDay News) – Higher visit-to-visit variability in blood pressure is associated with worse cognitive performance in older people at high risk of cardiovascular disease, according to a study published online July 30 in BMJ.
Behnam Sabayan, from Leiden University in the Netherlands, and colleagues examined the correlation between visit-to-visit variability in blood pressure and cognitive function using data from 5,461 participants (mean age, 75.3 years) who were at risk of cardiovascular disease and participated in the international PROspective Study of Pravastatin in the Elderly at Risk. During an average of 3.2 years, blood pressure was measured every three months. Outcome measures included four domains of cognitive function: testing selective attention, processing speed, and immediate and delayed memory. For 553 participants, a magnetic resonance imaging substudy measured structural brain volumes, cerebral microbleeds, infarcts, and white matter hyperintensities.
The researchers found that higher visit-to-visit variability in systolic blood pressure correlated with worse performance on all cognitive tests. Higher variability in systolic and diastolic blood pressure correlated with lower hippocampal volume and cortical infarcts. Higher variability in diastolic blood pressure correlated with cerebral microbleeds. The associations were all significant after adjustment for average blood pressure and cardiovascular risk factors.
"Higher visit-to-visit variability in blood pressure independent of average blood pressure was associated with impaired cognitive function in old age," the authors write.