High blood pressure variability a potential target for prevention of post-stroke dementia?

Nina Hilkens, Karin Klijn and Edo Richard, theme Disorder of movements, investigated whether blood pressure levels and blood pressure variability influence the risk of post-stroke dementia, in an attempt to find a potential target for prevention of post-stroke dementia. Findings are published in Journal of Hypertension on 11 March 2021.

Improvements in acute treatment of stroke, including removal of a blood clot from the brain, have led to better outcomes and increased survival. But one-third of stroke survivors develop dementia within five years after stroke. There are no effective strategies to prevent or lower the risk of dementia after stroke. High blood pressure and large variation in blood pressure may increase the risk of dementia in patients without stroke.  

They analyzed data from over 17.000 patients with ischemic stroke, who were followed-up for 2.5 years and underwent repeated blood pressure measurements. They found that the risk of dementia is elevated in those patients with high systolic blood pressure, but also in those with low blood pressure, implying a U-shaped association. This may have important implications for future blood pressure management after stroke. It suggests that lower may not always be better.

Furthermore, they observed that higher variability in blood pressure over successive measurements was associated with a linear increase in risk of dementia. Given the variable effect of antihypertensive treatment on blood pressure variability, with stronger effects for specific antihypertensive medication, for instance calcium channel blockers, these findings may impact on the optimal choice of antihypertensive treatment.

These results may inform future randomized controlled trials aiming to optimize blood pressure management after stroke, taking cognitive decline and dementia as important outcomes into account, next to the common outcomes recurrent stroke and mortality, which are not necessarily the outcomes valued most by patients.

Publication

Hilkens NA, Klijn CJM, Richard E. Blood pressure, blood pressure variability and the risk of post-stroke dementia. Journal of Hypertension, 2021 Mar 11. doi: 10.1097/HJH.0000000000002841. Online ahead of print.