What’s good for the heart is also good for the brain. A study released last month adds to growing research that blood pressure and other measures of vascular health have a role in cognitive health.
The SPRINT MIND study published in JAMA found that people with hypertension who received intensive treatment (resulting in blood pressure dropping below 120) to lower their blood pressure were less likely than those receiving standard blood pressure treatment (which brought blood pressure just under 140) to develop minor memory and thinking problems that often progress to dementia. This finding was a secondary outcome of the study and requires further research.
As a result of the encouraging findings, the U.S. Alzheimer’s Association is funding another two years of cognitive monitoring. For the time being, the trial has changed how the lead author of the study treats patients.
“I now offer those with blood pressure over 130 the intensive treatment,” says Dr. Jeff Williamson of Wake Forest School of Medicine. “I’ll tell them it will give you a 19% lower chance of developing early memory loss.”
Should you be changing how you manage your blood pressure to maintain your brain health? Here’s what the Medcan experts have to say.
“These findings are an important addition to our understanding of vascular and brain health”, says Dr. Beth Abramson, Director of Cardiology at Medcan. “Over the years the areas getting inadequate blood supply to the brain may lead to a gradual change in thinking or even stroke. Clinically, I advise my patients to work on lifestyle adjustments to reduce blood pressure in addition to taking appropriate medications with their health-care provider. Find out what works for you. For some people this means limiting alcohol intake, and for others it’s about reducing salt. Everyone can check their own blood pressure and know your numbers.”
“I would encourage all of us to work toward as low a blood pressure as possible with lifestyle changes, and discuss with our doctors additional medications on an individual basis,” says Dr. Abramson.
Would you advise your patients to follow the intensive blood pressure management strategy as advised by Dr. Williamson?
“Dr. Williamson’s statement is an an over-reach from the study findings,” says Dr. Sharon Cohen, Neurologist and Director of Toronto Memory Program. “As treatment targets for hypertension still need to be individualized based on age, presence of diabetes, and other factors. I agree that one should definitely consider more aggressive targets in certain individuals.
“Furthermore, it is important to realize that the study does not address the scenario of individuals who already have mild cognitive impairment. For cognitively healthy individuals concerned about future development of mild cognitive impairment and dementia, it would be fair to say that the take home message is that: Aiming for lower blood pressure measurements than previously recommended in the treatment of hypertension may reduce the chance of mild cognitive impairment by about 19%.”
“High blood pressure damages large and small blood vessels in the brain and increases the risk of stroke and dementia. Poorly managed blood pressure increases one’s risk of vascular dementia as well as Alzheimer’s disease,” says Dr. Cohen who was at the AAIC conference in July 2018 when the study was presented. “High blood pressure is a treatable risk factor and therefore should not be ignored.”
Estimates suggest that 8% of cases of Alzheimer’s disease may be attributable to mid-life hypertension. A 2014 Johns Hopkins study found that people with high blood pressure at midlife had greater decline in key thinking skills later in life than those with normal blood pressure readings. It was the equivalent of 2.7 extra years of brain aging in their 70s, 80s or 90s, enough time to push someone from mild cognitive impairment to a diagnosis of dementia.
Since high blood pressure has no (or very subtle) symptoms, people can go for years without addressing the condition, which hardens arteries and vessels that transport blood to key areas of the brain.
“It’s never too late to make changes to your lifestyle,” adds Dr. Abramson. Adopting lifestyle changes in diet and exercise could also reduce dementia risk in later life. Exercise triggers release of nourishing chemicals to the brain and helps with the creation of new brain cells and brain cell repair.
Dr. Abramson recommends that by age 40, it’s important to know your family history of hypertension (parents or siblings) and share this with your physician. It may be necessary to periodically keep track of blood pressure and take hypertension medication.
Achieving other markers of a healthy heart – such as not smoking, maintaining a healthy body weight and keeping cholesterol in check— also have a positive impact on your cognitive abilities.
Dr. Cohen regularly conducts dementia risk assessments and memory checks in cognitively healthy patients to establish an individual’s cognitive baseline should memory concerns arise in the future. Baseline cognitive testing is particularly relevant for those with a family history of dementia or other cognitive risk factors. Dr. Cohen notes that “over the past few year, more and more individuals are interested in a proactive approach to their brain health and we are responding to that important need.”
Dr. Cohen says the evidence for benefit to cardiovascular endpoints (i.e., the heart) was much greater than the evidence for benefit to the brain.
“The main trial ended early because of its unequivocal benefit to the cardiovascular endpoints while the primary cognitive endpoint (protection against dementia) was not met and the secondary cognitive endpoint (protection against mild cognitive impairment) was statistically significant but much less substantial than for cardiovascular events. This tells us that the parallel between brain and heart only goes so far.”