How blood pressure is key to brain health
“What many people don’t know is that heart health is vital for brain health. Managing heart health in midlife may be key for lowering global rates of dementia.”
Cardiovascular Factors for Brain Health
Maintaining healthy aging hinges significantly on the intricate relationship between cardiovascular health and brain function. Many key risk factors for dementia are also rooted in cardiovascular issues, emphasising the importance of maintaining a healthy heart for optimal brain health.
Hypertension, or high blood pressure, poses a significant risk, as it can lead to vascular damage and diminished blood flow to the brain. It can also contribute to Alzheimer’s disease pathology. Having hypertension in midlife (around 40-65 years) presents a 20-75% increased risk of later dementia. However, hypertensive individuals who receive blood pressure lowering treatment have demonstrated a decreased risk of dementia. Blood pressure presents an important modifiable prevention avenue for dementia. However, there are many gaps in our understanding of underlying mechanisms and treatment. One key gap is in the way we measure blood pressure.
24HR BLOOD PRESSURE Blood pressure varies throughout the day in response to a wide variety of factors such as: eating, exercise, hydration, caffeine, stress, having a full bladder, or being in a seated or standing position. Over the course of the day and night, blood pressure exhibits a distinct 24hr pattern. However, blood pressure is most commonly measured at a single time point during the day, ignoring these natural variations. This is what we call ‘office blood pressure’. As a result of measuring blood pressure in this way, individuals can exhibit masked hypertension - where blood pressure looks normal on office readings but is high on home readings either during the day or night, and are often missed in medical screening. Further, individuals with white coat hypertension can be misdiagnosed.
Individual differences in these 24hr patterns are also strong predictors of cardiovascular health and mortality, however are poorly understood in their relationship to dementia. Part of our research at BACH aims to help to further understand how 24hr blood pressure patterns relate to brain health.
BACH is a community cohort study currently recruiting adults ages 55-80 years of age, with no major neurological illness. The 5-year study involves: blood tests, tests of learning and memory, a brain MRI scan and an optional lumbar puncture, wearing a sleep and activity monitoring watch for 14 days, 24hr home blood pressure monitor, and an overnight PSG sleep study at home.
The aim of the study is to provide foundations for important scientific discoveries about improving brain health in the face of ageing, including furthering our understanding of 24hr blood pressure and brain health relationships and mechanisms.
FROM THE ARTICLE
The Association Between 24-Hour Blood Pressure Profiles and Dementia
The Journal of Alzheimer’s Disease, 2023 https://doi.org/10.3233/jad-230400
Madeline Gibson, Dr Stephanie Yiallourou, and A/Prof Matthew P. Pase.