Fluctuations in home-monitored blood pressure may raise dementia risk

August 8, 2017
Credit: CC0 Public Domain

Whether or not you have high blood pressure, your risk of dementia may be higher if your pressure varies a lot from day to day, according to new research in the American Heart Association's journal Circulation.

"Home monitoring of may be useful to assess the future risk of ," said lead study author Tomoyuki Ohara, M.D., Ph.D., an assistant professor of neuropsychiatry at the Graduate School of Medical Sciences at Kyushu University in Fukuoka City, Japan.

Previous studies reported a heightened risk of cognitive impairment and dementia in people with large variations in pressure from one doctor visit to another, but this is the first study to use to examine the association between blood pressure variability and dementia risk.

Home monitoring may be more reliable than office measurements because of the "white-coat" effect, in which some people have higher blood pressure in the doctor's office than they do at home.

Researchers asked more than 1,600 Japanese adults without dementia (average age 71; 56 percent female) to measure their blood pressure at home for one month. On average participants measured their blood pressure three times each morning prior to eating breakfast or taking medication. Participants included both those with normal and high blood pressure. About 4 in 10 were taking medication for high blood pressure. Researchers reviewed the month of home , conducted cognitive testing to uncover the development of dementia and reviewed records for the occurrence of stroke.

During the five-year follow-up, 134 subjects developed Alzheimer's disease and 47 developed , which results from diminished blood flow to the brain and is often related to the occurrence of small strokes.

Compared with participants who had the most stable blood pressure, and after adjusting for other dementia risk factors and the average blood pressure levels themselves, those with the highest variability in systolic (higher number) blood pressure were:

  • more than twice as likely to develop any type of dementia (2.27 times) or Alzheimer's disease (2.2 times), and
  • nearly three times more likely to develop vascular dementia (2.79 times).

In addition, among participants with greater blood pressure variability, higher further increased the risk of vascular dementia but did not change the heightened risk of Alzheimer's disease.

"Further studies are needed to clarify whether day-to-day blood pressure variation is an indicator of future dementia, or whether it might be a target for interventions aimed at preventing dementia," Ohara said. "Blood pressure variation may indicate high blood pressure that is inadequately treated, but other factors, such as mental or physical stress, sleep deprivation, an irregular lifestyle, or damage to nerves that control involuntary bodily functions, can also contribute."

The American Heart Association recommends home monitoring for all people with high blood pressure to help the healthcare provider determine whether treatments are working.

"This research adds to the evidence that blood pressure fluctuations can have serious consequences and highlights the importance of getting frequent, accurate measurements to provide patients with the best treatment plan to prevent those consequences," said American Heart Association volunteer Mary Ann Bauman, M.D.

"Home blood monitoring is becoming more important for diagnosing and managing , thus making it vital that providers ensure their patients understand not only their numbers, but also how to use their home monitors appropriately," said Bauman, medical director of INTEGRIS Family Care Central in Oklahoma City.

Participants in this study were part of the large, ongoing Hisayama Study, which has tracked for decades the health and cognitive performance in adult residents of a suburb of Fukuoka City, Japan. Because the study population was Japanese, the findings may not apply to a Western population or to other ethnic groups with different lifestyles or genetic backgrounds.

Explore further: High blood pressure linked to vascular dementia

Related Stories

High blood pressure linked to vascular dementia

May 18, 2016
High blood pressure could significantly raise the risk of developing the second most common form of dementia, according to a new study from The George Institute for Global Health.

Blood pressure: know your numbers

April 18, 2017
(HealthDay)—Having high blood pressure makes you more likely to have heart disease or a stroke. But because high blood pressure doesn't usually cause warning symptoms, you could be at risk without even knowing it.

Sudden blood pressure drops associated with long-term dementia risk

October 11, 2016
Orthostatic hypotension—low blood pressure when suddenly standing up—is associated with a 15 percent increase in a person's long-term risk of dementia, including Alzheimer's disease, according to a twenty-four year study ...

Heart risks in middle age boost dementia risk later in life

February 22, 2017
People who have heart disease risks in middle age - such as diabetes, high blood pressure or smoking - are at higher risk for dementia later in life, according to research presented at the American Stroke Association's International ...

High blood pressure and brain health are linked

October 10, 2016
High blood pressure, especially in middle age, is associated with an increased risk of cognitive impairment later in life, according to a new statement from the American Heart Association.

Around-the-clock monitoring may unmask hypertension in African-Americans

May 16, 2016
Wearing an ambulatory blood pressure monitoring device that measures blood pressure around-the-clock may help identify African Americans who have masked or undetected high blood pressure outside of the doctor's office, a ...

Recommended for you

Research suggests new pathways for hyperaldosteronism

December 7, 2017
A new study led by researchers at Sanford Burnham Prebys Medical Discovery Institute (SBP), in collaboration with researchers at Eunice Kennedy Shriver National Institute of Child Health and Human Development, part of the ...

One-dose gene therapy produces clotting factor, safely stops bleeding in hemophilia B patients

December 6, 2017
A team of gene therapy researchers has reported positive results in a phase 1/2 clinical trial for the inherited bleeding disorder hemophilia B. A single intravenous infusion of a novel bioengineered gene therapy treatment ...

Clot-busting drugs not recommended for most patients with blood clots

December 6, 2017
Not all patients with blood clots in their legs - a condition known as deep vein thrombosis - need to receive powerful but risky clot-busting drugs, according to results of a large-scale, multicenter clinical trial.

Mitochondrial protein in cardiac muscle cells linked to heart failure, study finds

December 5, 2017
Reducing a protein found in the mitochondria of cardiac muscle cells initiates cardiac dysfunction and heart failure, a finding that could provide insight for new treatments for cardiovascular diseases, a study led by Georgia ...

Blood pressure declines 14 to 18 years before death

December 4, 2017
Blood pressure in the elderly gradually begins to decrease about 14 or so years before death, according to a new study published today in the JAMA Internal Medicine.

Study links common male medical condition and vascular disease

December 1, 2017
Men who suffer symptoms from varicoceles, enlarged veins in the scrotum, are more likely to develop vascular disease and metabolic disease, such as diabetes, according to a study by Stanford University School of Medicine ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.