Research Says This Health Condition Can Make You 61% More Likely to Develop Dementia
Heart disease is the No. 1 killer in America and, chances are, we all know someone who has been impacted. (My dad, for instance, has recovered from a heart attack, and my grandpas on both sides had open-heart surgery to address severe arterial blockages.) So I try to follow the American Heart Association's Life's Simple 7 for a heart-healthy lifestyle, and I aim to fill my weekly menu with as many of these best foods for heart health as possible.
As with any health topic, we continue to learn more each month about the most effective ways to prevent—or at least delay—chronic health conditions (even those that we're genetically predisposed to). And since I, at age 34, hope to have many healthy decades ahead, my ears perked up when I spotted this recent finding: Compared to their peers with normal blood pressure, people who are diagnosed with high blood pressure (or hypertension) from ages 35 to 44 tend to have smaller brain size and are at higher risk of developing dementia, according to new research published in the October 2021 issue of the AHA journal Hypertension.
"Hypertension is very common in middle-aged people [45 to 64 years], and early-onset high blood pressure is becoming more common. Although the association among hypertension, brain health and dementia in later life has been well-established, it was unknown how age at onset of hypertension may affect this association. If this is proven, it would provide some important evidence to suggest earlier intervention to delay the onset of hypertension, which may, in turn, be beneficial in preventing dementia," Mingguang He, M.D., Ph.D., senior author of the study and professor of ophthalmic epidemiology at the University of Melbourne in Australia, tells the AHA.
The results, the scientists confirm, suggest that young adulthood is prime time for keeping tabs on blood pressure—and aiming to keep it within healthy limits—to control or postpone the onset of cognitive decline. (In case you missed it, another new study found that one particular diet can lessen the risk of cognitive decline—even if you're already experiencing symptoms.) As a refresher, and a hint to why the head and the heart are connected, about 25% of the blood that pumps out of the heart flows to the brain.
To land on this conclusion, the researchers dove into data from the U.K. Biobank, a compilation of health information from 500,000 volunteer participants based in the U.K. To measure brain size changes, they tracked MRI measures of brain volume between the 11,399 people with high blood pressure diagnosed at different ages:
- Before age 35
- 35 to 44 years old
- 45 to 54 years old
The scientists compared these brain volume rates with 11,399 participants who were never diagnosed with high blood pressure (over 130/80 mmHG, per the AHA guidelines), then matched similar participants from each group based on age and "multiple health-related variables."
Participants entered the study group between 2006 and 2010, and the MRIs were taken between 2014 and 2019. In each age group, the brain volume was smaller among those with high blood pressure. And hypertension diagnosed before age 35 was linked with the greatest change (aka decrease) in brain volume.
"Individuals who had hypertension diagnosed at younger ages had smaller brain volumes on these one-time measurements. Future research with brain volumes measured at multiple time points could confirm whether hypertension diagnosed at a younger age is associated with a greater decrease in brain volume over time," adds Xianwen Shang, Ph.D., M.P.H., lead author of the study and a research fellow at the Guangdong Provincial People's Hospital in Guangzhou, China.
But that brain volume change doesn't necessarily mean a dementia diagnosis is imminent. So to evaluate the dementia risk, the scientists looked at how many of the participants developed cognitive decline during a nearly 12-year follow-up period. Fascinatingly, although vascular dementia risk was 80% higher among those diagnosed with high blood pressure before age 35, they found fewer cases of dementia among that cohort, and the association with high blood pressure was not statistically significant. The risk of dementia from any cause was drastically higher, however, to the tune of 61%, among those diagnosed with high blood pressure between the ages of 35 and 44. (This was compared to those whose BP fell within a normal range, of less than 120/80 mmHG, according to the AHA.)
"No relationship was found between age at hypertension diagnosis and the risk of Alzheimer's disease, a type of dementia linked to proteins that disrupt brain function," the authors explain. (Dementia is a decline of cognitive functions like problem-solving, memory and language, enough that daily life is impacted. Alzheimer's disease is a more severe form that falls under the umbrella term of "dementia," that also involves a change in thinking and behavior.)
"Our study's results provide evidence to suggest an early age at onset of hypertension is associated with the occurrence of dementia and, more importantly, this association is supported by structural changes in brain volume," Shang says.
Looking ahead, the investigators hope to see if other medical challenges—including diabetes and stroke—may also be related to early adulthood diagnosis of high blood pressure. They also hope to expand the diversity of the population studied, as this group was majority Caucasian. Still, if you, like me, are at high risk for heart disease, are in young- to mid-adulthood and it's been a minute since you've had your blood pressure checked, it certainly can't hurt to take a pulse. If your blood pressure results do come back high, your doctor can help advise you about some lifestyle changes that can help move the needle. And in case you want to study up ahead of time, these 3 things can help lower your high blood pressure—even when medicine isn't helping.