- Researchers say high blood pressure in the elderly can accelerate the onset of cognitive decline.
- Treatment of hypertension may delay the progress of this decline.
- High blood pressure can harden the walls of the arteries in the brain and cause gut microbes.
New research suggests that there are even more reasons for middle-aged adults and adults to monitor their blood pressure closely.
In addition to the higher risk of stroke, heart attack and other diseases, research presented at the American Heart Association (AHA) Hypertension 2019 Scientific Sessions adds to the growing body of evidence that high blood pressure (hypertension) may also affect to the mind of a person with advancing age.
It also suggests that treating the condition may help prevent cognitive decline.
The AHA estimates that more than 100 million adults in the United States have high blood pressure. This is almost half of the country's adult population.
Therefore, the organization says that research into how the condition affects the blood vessels in the brain is important.
In a recent study, researchers at Columbia University in New York analyzed data collected from nearly 11,000 adults enrolled in the China Longitudinal Health and Retirement Survey (CHARLS).
They sought to determine whether high blood pressure – and whether the person treating it with blood pressure – affected a person's memory, language, and thinking,
Chinese researchers interviewed people who took part in the study in their homes about their high blood pressure pressure using a blood pressure threshold of 140/90 mm Hg. The AHA notes that their hypertension guidelines are lower at 130/80 mm Hg.
The researchers also asked the study participants how they were treating their condition. In addition, they asked participants to take tests that assess their cognitive abilities, such as recalling words as part of a memory test.
The study was observational, meaning that researchers relied on what people told them, not medical records and other less subjective measures. He also did not examine whether some treatments were more successful than others.
But researchers say they have noticed that people over 55 with high blood pressure have lost their mental abilities faster than those who have not.
They also report that people who treat their condition have the same degree of cognitive decline as those without high blood pressure.
"We believe that efforts should be made to expand screening for high blood pressure, especially for at-risk groups, as so many people are unaware that they have high blood pressure to be treated," Shumin Rui , author of the study, a graduate of Columbia University and associate biostatics at IQVIA consultants, said in a press release.
Rui also said while the study focused on middle-aged adults and adults in China, the results could be applied to the population elsewhere.
"We need to better understand how treatment for high blood pressure can prevent cognitive decline and look at how high blood pressure and cognitive decline are observed," she said.
Jagdish Hubchandani, PhD, associate professor and professor of health science at Ball University in Indiana, stated that the exciting part of the study was that it could be the first study on high blood pressure and cognitive decline in the Chinese population.  He said that this means that earlier discoveries from western countries are valid for different populations, where diet, lifestyle, environment and social circumstances can vary greatly.
"With this new study, and to some knowledge, there is more evidence that high blood pressure can accelerate the process of age-related cognitive decline, especially if left untreated," Dr. Hubchandani told Healthline.
Other experts say the study adds an interesting perspective to what has been known for quite some time: There is a link between high blood pressure and cognitive decline in the elderly.
Part of this could be how hypertension hardens the walls of the arteries, creates microtubules in the brain, or reduces blood flow to important brain tissue, which can slowly build up to bigger problems over time.
This is also part of the reason that it is one of the first tests performed when you visit your doctor's office or enter the emergency room door.
Stephen Sidney, MD, senior researcher at the Kaiser Permanente Research Unit in Northern California, stated that high blood pressure is considered a risk factor for cognitive impairment and dementia.
This is also one of many factors that contribute to hardening. of the arteries that provide oxygen to the brain.
"It takes many years and even decades for this to happen until the supply of oxygen to the brain is compromised," Dr. Sydney tells Healthline.
Meanwhile, at Kaiser Permanente in Southern California, Columbus Batiste, MD, a cardiologist, medical professionals have known for years that there is a link between high blood pressure and cognitive decline in people between the ages of 40 and 60.
He said studies show that for every 10-unit increase in systolic blood pressure – the peak number in measurement – there is a 9 percent drop in cognitive function.
One such study – the risk of atherosclerosis in communities – shows hypertension and middle-aged hypertension is associated with a decline in cognitive performance and people who have not treated their high blood pressure are at greater risk for it.
Dr. Batista said one of the main reasons could be when the walls of the arteries harden, potentially leading to small hemorrhages in the brain (microblots).
"Microfibers are often found in people with high blood pressure, even if one is not diagnosed with a stroke," he said. "These microcells have been suggested as a cause of cognitive impairment."
They are also associated with brain tissue death and small strokes, which often have no symptoms as they occur but may contribute to cognitive impairment.
All are good reasons for people to treat their high blood pressure.
Batista said that the first step in treating high blood pressure was "knowing your numbers," as they gave an idea of the risk factors of a person not only for cognitive impairment, but also for heart failure, heart attack, stroke and kidney failure.
The second step is to work with your health care team to start "aggressive lifestyle intervention," he says.
This may include daily exercise as well as a diet based on eating berries, green leafy vegetables and legumes while eliminating. processed and packaged foods high in sodium.
Other interventions may include relaxing exercises to combat stress, get more sleep, and screen for sleep apnea.
"If lifestyle measures are not effective, it is important that you talk to your doctor about looking at the medicines again, remembering to report if there is any concern as there is no one-size-fits-all approach," says Batista.