High blood pressure is an established risk factor for neurodegeneration and cognitive decline.
Valentin Fuster, MD, president of Mount Sinai Fuster Heart Hospital in New York City, told this news organization. “There is no question in the literature that untreated high blood pressure may lead to dementia,” he said. “The open question is whether treating blood pressure is sufficient to decrease or stop the progress of dementia.”
Studies are mixed, but recent research suggests that addressing hypertension does affect the risk for dementia. A secondary analysis of the China Rural Hypertension Control Project reported at the American Heart Association (AHA) Scientific Sessions in 2023 but not yet published showed that the 4-year blood pressure–lowering program in adults aged 40 or older significantly reduced the risk for all-cause dementia and cognitive impairment.
Similarly, a post hoc analysis of the SPRINT MIND trial found that participants aged 50 or older who underwent intensive (< 120 mm Hg) vs standard (< 140 mm Hg) blood pressure lowering had a lower rate of probable dementia or mild cognitive impairment.
Other studies pointing to a benefit included a pooled individual participant analysis of five randomized controlled trials, which found class I evidence to support antihypertensive treatment to reduce the risk for incident dementia, and an earlier systematic review and meta-analysis of the association of blood pressure lowering with newly diagnosed dementia or cognitive impairment.
How It Might Work
Some possible mechanisms underlying the connection have emerged.
“Vascular disease caused by hypertension is clearly implicated in one form of dementia, called vascular cognitive impairment and dementia,” Andrew Moran, MD, PhD, associate professor of medicine at Columbia University Vagelos College of Physicians and Surgeons in New York City, told this news organization. “This category includes dementia following a stroke caused by uncontrolled hypertension.”
“At the same time, we now know that hypertension and other vascular risk factors can also contribute, along with other factors, to developing Alzheimer dementia,” he said. “Even without causing clinically evident stroke, vascular disease from hypertension can lead to subtle damage to the brain via ischemia, microhemorrhage, and atrophy.”
“It is well known that hypertension affects the vasculature, and the vasculature of the brain is not spared,” agreed Eileen Handberg, PhD, ARNP, a member of the Hypertension Workgroup at the American College of Cardiology (ACC) and a professor of medicine and director of the Cardiovascular Clinical Trials Program in the University of Florida, Gainesville, Florida. “Combine this with other mechanisms like inflammation and endothelial dysfunction, and add amyloid accumulation, and there is a deterioration in vascular beds leading to decreased cerebral blood flow,” she said.
Treating hypertension likely helps lower dementia risk through “a combination of reduced risk of stroke and also benefits on blood flow, blood vessel health, and reduction in neurodegeneration,” suggested Mitchell S.V. Elkind, MD, chief clinical science officer and past president of the AHA and a professor of neurology and epidemiology at Columbia University Irving Medical Center in New York City. “Midlife blood pressure elevations are associated with deposition of amyloid in the brain, so controlling blood pressure may reduce amyloid deposits and neurodegeneration.”