Controlling Blood Pressure May Help Support Brain Health

Most people know that high blood pressure can lead to heart attacks and strokes, two very good reasons to keep it under control. But here’s another equally important reason: Treating high blood pressure may reduce your risk of cognitive decline or dementia.

Researchers have been looking at the connection between high blood pressure and brain health for decades. Studies that followed large groups of adults found that high blood pressure in middle age in particular was associated with worsening performance on mental-skills tests as participants grew older.

Research studies drive home this message: One thing older people can do to help protect their memory and thinking skills as they age is to get a handle on their high blood pressure.

“The effect of high blood pressure on the brain is cumulative. The longer you have high blood pressure, the greater the damage it does over time,” American Heart Association President Mitchell Elkind said in an interview. A professor of neurology and epidemiology at Columbia University, Elkind said researchers have known for several years “that high blood pressure is linked to cognitive decline. We can see changes in thinking ability as measured by test scores over time, as well as dementia.”

That’s because ongoing high blood pressure starts to damage the blood vessels in the brain, Elkind explained, making them more likely to rupture and bleed. “Even tiny bits of damage to the vessels, over time, adds up. It’s like [the brain’s version of] heart failure — a progressive decline in function as time goes by.”

But research suggests that treating the condition — with medication, if necessary, as well as through changes in diet and exercise — can help stave off mental decline. There are currently more than 100 million American adults with high blood pressure, yet only about 1 in 4 have their condition under control.

Researchers from the National University of Ireland Galway conducted a major study, published in May 2020 in JAMA, in which they found that lowering blood pressure by taking medication “was significantly associated with a lower risk of dementia or cognitive impairment.”

The researchers analyzed data from 14 randomized clinical trials involving more than 96,000 people (average age 69) who had an average blood pressure reading of 154/83. For most adults, a reading of below 120/80 is considered healthy.

Twelve of the trials found that participants who took medication to lower blood pressure to a healthy range reduced their risk of developing dementia or cognitive impairment by about 7 percent over a four-year period, compared with those in the control groups. “When you consider how common dementia is in the population — 50 million people worldwide — effective treatment and control of high blood pressure would have a major impact on preventing dementia,” coauthor Conor Judge said in a statement.

The 2019 “Brain-Heart Connection” report by AARP’s Global Council on Brain Health, an international collaboration of scientists and medical experts, also recommends that if your blood pressure is higher than 130/80, you should talk to your health care provider about steps to bring it under control.

Problems with blood pressure may be more common among those older than 60, but “there is overwhelming evidence that taking care of your heart is one of the most important things you can do to lower your risk of dementia and keep your brain healthy as you age,” the report states.

Other studies with similar findings include:

• The federal SPRINT MIND trial, a major, multiyear national study funded by the National Institutes of Health, reported in January 2019 that lowering blood pressure was linked to a reduced risk of mild cognitive impairment and the combined risk of MCI and dementia.
• A January 2019 study, published in the American Heart Association (AHA) journal Hypertension, looked at blood pressure and cognitive decline in about 22,000 middle-aged and older Black and white adults over eight years. Researchers found there was a faster mental decline in Blacks with high blood pressure than in Whites, and in men compared with women. According to government data, high blood pressure is more common in Black adults than in white, Asian or Hispanic adults, and Blacks tend to have poorer control of their condition than whites.
• For a recent preliminary study presented at the AHA’s 2019 scientific sessions on hypertension, researchers from Columbia University analyzed data collected from interviews and the results of mental-acuity tests from nearly 11,000 middle-aged and older Chinese adults enrolled in a four-year study. They found that the mental abilities of participants 55 and older with untreated high blood pressure declined faster than those of subjects taking medication or those with normal blood pressure.

What you should know:

Neurologist Mitchell Elkind is a past president of the American Heart Association and a specialist in stroke prevention and other issues of brain health. In an interview with AARP, he shares the following for people dealing with high blood pressure.

• You’re at increased risk during the COVID-19 pandemic. “People should be aware that during this pandemic, those with high blood pressure are at increased risk of complications from the virus and at a higher risk for hospitalization and critical illness,” Elkind says. Keeping your blood pressure under control is critically important during this global crisis.
• Consider getting a blood pressure machine for your home. People who use home blood pressure monitors maintain better control of their blood pressure numbers than those who don’t, Elkind says, possibly because blood pressure can be checked more regularly and in a less stressful environment. If you have a home machine, he suggests checking your blood pressure at the same time each day, “before you take your blood pressure medication, so you can see what your pressure is when the medication is wearing off.”
• Take steps for an accurate blood pressure reading at the doctor’s office. Here are Elkind’s suggestions for an accurate reading: Make sure your bladder is empty so you’re not tense and clenching your muscles. Don’t drink a caffeinated beverage within 30 minutes of an office visit, which can raise blood pressure. The blood pressure cuff should not be placed over heavy clothing, such as a sweater, as that can affect the reading. Make sure your arm is resting at about heart level when the reading is done — don’t let your arm dangle. If your reading is unusually elevated, ask for it to be retaken in five or 10 minutes, to be sure it’s accurate.