October 18, 2023
High blood pressure, or hypertension, has been linked to an increased risk of Alzheimer’s disease and other forms of dementia. But taking medications to keep blood pressure in check can help to protect the brain and keep dementia at bay, according to a new analysis of data from a collection of large-scale aging studies.
The new study found that older men and women whose hypertension is under control have no greater risk of dementia than someone without high blood pressure. Older adults who regularly took their blood pressure meds had a 26 percent lower risk of developing Alzheimer’s disease and other forms of dementia than their peers with untreated hypertension.
For the analysis, researchers pooled data from 17 different studies involving more than 34,000 older men and women from around the world. They ranged in age from 60 to over 100, with a mean age of 72. None had dementia at the start of the study.
Among the study group, almost half were taking medications to treat high blood pressure. Another 2,881 had hypertension but were not taking drugs to lower it, while 10,402 served as healthy controls.
The studies followed participants for an average of four to five years, with some of the follow-up periods lasting up to 15 years. They found that older adults with untreated high blood pressure were 42 percent more likely to develop dementia during the study period compared to healthy older adults. Those whose blood pressure was kept under control were at no higher risk of developing dementia than their healthy counterparts, even among the very oldest participants in their 80s and 90s. The findings were published in JAMA Network Open.
Nearly half of Americans have high blood pressure, and the prevalence increases with age. But there typically are no symptoms, and many people don’t even know they have the condition. High blood pressure can lead to heart and blood vessel disease as well as strokes and kidney disease. It can raise the risk of developing any form of dementia in old age by up to 60 percent, including a 25-percent increased risk of developing Alzheimer’s disease.
This study shows that keeping blood pressure in check can mitigate those risks. Experts generally advise that it is best to keep blood pressure at 120/80.
Hypertension can arise because of genetic factors, but also because of lack of exercise and a poor diet. Excessive alcohol use or a high-sodium diet, for example, can contribute to high blood pressure in some people.
While the first-line treatment for high blood pressure is regular exercise and a heart-healthy diet, blood pressure medications are also often needed. As this study confirms, they may be especially important for maintaining memory and thinking skills as we age. If your doctor prescribes blood pressure drugs, it is important to keep taking them and to have your blood pressure checked regularly.
By ALZinfo.org, The Alzheimer’s Information Site. Reviewed by Eric Schmidt, Ph.D., Fisher Center for Alzheimer’s Research Foundation at The Rockefeller University.
Source: Matthew J. Lennon, MD; Ben Chun Pan Lam, PhD; Darren M. Lipnicki, PhD; et al: “Use of Antihypertensives, Blood Pressure, and Estimated Risk of Dementia in Late Life: An Individual Participant Data Meta-Analysis.” JAMA Network Open, September 12, 2023