Blood pressure variability implicated in dementia risk

Individuals with higher blood pressure (BP) variability (BPV) are at increased risk of developing probable dementia despite good BP control, according to a post hoc analysis of the SPRINT MIND* trial.

The analysis included 8,379 patients, with a mean of 7.8 BP measurements obtained over a 600-day observation period. The mean systolic BP was 128.5 mm Hg, while the mean values in the tertiles of BPV were 6.3, 10.3, and 16.3 mm Hg, respectively.

Over a mean follow‐up of 3.2 years, 316 (3.8 percent) patients developed dementia. The incidence rates of dementia increased progressively across the tertiles of BPV (2.4 percent, 3.6 percent, and 5.4 percent, respectively; p<0.001).

Multivariable Cox proportional hazards regression showed that compared with the lowest tertile of BPV, the highest tertile was associated with almost a 70-percent higher risk of dementia (adjusted hazard ratio [HR], 1.69, 95 percent confidence interval [CI], 1.25–2.28).

Results for the secondary outcomes were consistent, such that the highest tertile of BPV conferred heightened risks of both mild cognitive impairment (MCI; adjusted HR, 1.40, 95 percent CI, 1.14–1.71) and the composite of dementia or MCI (adjusted HR, 1.43, 95 percent CI, 1.20–1.71).

The Kaplan‐Meier curves indicated that the effect of higher BPV on dementia risk was observed in both the standard and intensive BP control arms.

More studies are needed to determine ways to reduce BPV and if its reduction helps lower the risk of cognitive impairment and dementia.

*Systolic Blood Pressure Intervention Trial Memory and Cognition in Decreased Hypertension