As widespread awareness of the significance of dementia continues to grow, more and more patients want to know how they can prevent it. A recent study uncovered a potential opportunity for younger patients to decrease their risk for dementia later in life: keep blood pressure within normal bounds and avoid large increases, even within those normal bounds.
The study, conducted by Christopher A. Lane, PhD, and colleagues at the University College of London, was published in Lancet Neurology on August 20, 2019. It showed that early middle age may be a time of particular vulnerability to both high and rising blood pressure.
The longitudinal study followed a cohort of individuals born in the UK in 1946. Those who had higher pressures or larger increases in blood pressure between ages 36 and 53 also had more white matter lesions and smaller brain volume later in life.
Specifically, a 10 mmHg increase in systolic BP from age 43 to 53 showed 7 percent more white matter lesions, while a 10 mmHg increase in diastolic BP was associated with a 15-percent increase in white matter lesions.
In addition, a 10mmHg increase in diastolic pressure from age 36 to 43 was correlated with a 6.9 ml decrease in brain volume by around age 70. Greater increases in diastolic pressure were associated with further loss of brain volume.
The connection between blood pressure and dementia is not new, but how and when blood pressure affects risk is not completely understood. So, while this study is bad news for those individuals with changes in white matter and brain volume, it is good news for those who hope to modify their risk for dementia.
According to Lenore J. Launer of the National Institute on Aging in an editorial published alongside the Lancet article, more efforts are needed to fully “understand the complexity of blood pressure-cognitive-related outcomes,” but the connection between blood pressure and pathological changes typically associated with cognitive decline “is unlikely to be a chance finding.”
The authors suggest that monitoring routine blood pressure measurements may need to begin at around 40 years of age or earlier, and decisions to begin treatment “should account for blood pressure change over time.”
As hypertension affects millions of people, clinical services and public health interventions are necessary to prevent brain pathology associated with cognitive decline. And for the patient looking to prevent dementia later in life, these interventions will offer concrete actions they can take.