Researchers from the US National Institutes of Health have found that intensively controlling a person’s blood pressure is more effective at slowing the accumulation of white matter lesions in the brain than standard treatment of high blood pressure.
The results complement a previous study published by the same research group which showed that intensive treatment significantly lowered the chances that participants developed mild cognitive impairment.
White matter is made up of billions of thin nerve fibres, called axons, that connect the neurons with each other. The fibres are covered by myelin, a white fatty coating that protects axons from injury and speeds the flow of electrical signals. White matter lesions, which appear bright white on MRI scans, represent an increase in water content and reflect a variety of changes inside the brain, including the thinning of myelin, increased glial cell reactions to injury, leaky brain blood vessels, or multiple strokes. These changes are associated with hypertension.
The researchers also reported slightly more loss of brain volume in the intensive treated group than those in the standard treatment. The effect was seen predominantly in males. However, the authors noted this loss was generally very small and of unclear clinical significance.
Walter Koroshetz, the study’s lead author, said: ‘These initial results support a growing body of evidence suggesting that controlling blood pressure may not only reduce the risk of stroke and heart disease but also of age-related cognitive loss. I strongly urge people to know your blood pressure and discuss with your doctors how to optimise control. It may be a key to your future brain health.’
These observations were tested in a randomised clinical trial, called SPRINT Memory and Cognition in Decreased Hypertension (MIND), which examined whether controlling blood pressure levels could prevent or slow white matter lesion progression and ageing brain disorders.
In future the researchers plan to look at how controlling blood pressure may affect the accumulation of white matter lesions in critical regions of the brain affected by ageing brain disorders and what factors may make some people more responsive to treatment.