BP variability, SBP linked to dementia risk in ischaemic stroke patients

A U-shaped association exists between achieved systolic blood pressure (SBP) and dementia among patients with a recent noncardioembolic ischaemic stroke, reveals a study, noting that high BP variability may contribute to an increased risk of poststroke dementia.

Overall, 17,064 patients with noncardioembolic ischaemic stroke from the Prevention Regimen for Effectively avoiding Second Strokes trial were included in this analysis. The authors examined the data as a single observational cohort and analysed the mean achieved SBP and diastolic (D)BP and BP variability, defined as coefficient of variation.

Finally, logistic regression analysis was carried out to assess the relationship between BP and dementia, correcting for sociodemographic factors and cardiovascular risk factors.

A total of 817 patients had a diagnosis of dementia (2.1 per 100 person-years) during 39,818 person-years of follow-up. Mean SBP showed a significant nonlinear association with the risk of dementia, indicating a U-shaped correlation.

Of note, mean SBP of 120–129 mm Hg correlated with a significantly higher dementia risk compared with 130–139 mm Hg (odds ratio [OR], 1.28, 95 percent confidence interval [CI], 1.03–1.58). In contrast, no U-shaped association was found between mean DBP and dementia, and no significant correlation existed between mean DBP categories and dementia.

Additionally, higher BP variability correlated with a higher risk of dementia (OR, 1.06 per point increase, 95 percent CI, 1.02–1.04), independent of mean SBP.

“High BP and BP variability are potential, modifiable risk factors of poststroke dementia,” the investigators noted.