The interplay between high blood pressure and brain health is one scientists continue to shed new light on, with studies increasingly linking hypertension to a decline in cognitive function later in life. New research has drilled into the details around when exactly this relationship begins to take shape, finding that it not only begins earlier than suspected, but that even those with blood pressure at the higher end of the normal recommended range can be at risk of premature brain aging.
A growing body of research is strengthening the connection between high blood pressure and mild cognitive impairment, dementia and Alzheimer's, while one study even uncovered a link with diabetes. By the same token, studies have also suggested that treating high blood pressure can slow the rate of cognitive decline, and that this could even be achieved with common hypertension drugs to boost blood flow.
But there remain many blanks to fill in, both in terms of how blood pressure affects the brain and at what stage in life it begins to do so. Seeking answers to these questions, a study led by scientists at Australian National University analyzed 2,000 brain scans of 686 healthy individuals between the ages of 44 and 76, and then combined this with blood pressure data on each subject collected up to four times across a 12-year period.
It's important we introduce lifestyle and diet changes early on in life to prevent our blood pressure from rising too much, rather than waiting for it to become a problem
This allowed the researchers to determine the brain age of each person, a standard measure of brain health, and gain new insights into the influence high blood pressure can have on it. In adults, a normal blood pressure means a reading of below 120/80, while optimal blood pressure is closer to 110/70. According to the team's analysis, even those at the higher end of this "healthy" range were at risk of accelerated brain aging, and that aiming for the optimal blood pressure can make all the difference.
"It's important we introduce lifestyle and diet changes early on in life to prevent our blood pressure from rising too much, rather than waiting for it to become a problem," say co-author Professor Walter Abhayaratna. "Compared to a person with a high blood pressure of 135/85, someone with an optimal reading of 110/70 was found to have a brain age that appears more than six months younger by the time they reach middle age."
These findings have led the researchers to call for a revision of health guidelines. But because it takes some time for elevated blood pressure to begin to influence the brain, the scientists say the study also highlights the need to pay attention to these readings far earlier in life, and that the effects could begin building even when healthy people are in their 20s.
"This thinking that one's brain becomes unhealthy because of high blood pressure later in life is not completely true," says study author Professor Nicolas Cherbuin. "It starts earlier and it starts in people who have normal blood pressure."
The research was published in the journal Frontiers in Aging Neuroscience.
Source: Australian National University
