UC Irvine Health System
01/09/2025 | Press release | Distributed by Public on 01/10/2025 17:02
Study challenges traditional risk factors for brain health in the oldest-old
Study challenges traditional risk factors for brain health in the oldest-old
Findings highlight potential significant role of certain medications in avoiding dementia
January 09, 2025
Orange, Calif. - A study led by the University of California, Irvine has found cardiovascular conditions such as high blood pressure and diabetes, which are known to contribute to brain blood vessel damage in younger populations, not to be associated with an increased risk of such harm in individuals 90 and older.
The work, published online today in the journal Alzheimer's & Dementia: The Journal of the Alzheimer's Association, suggests that the relationship among blood pressure, vascular health and brain aging is more complex than previously thought.
"For decades, we've known that factors like high blood pressure and diabetes can injure blood vessels in the brain, increasing the risk for cognitive decline and dementia. However, our research found that these patterns may change as people age," said corresponding author Dr. Ravi Rajmohan, clinical instructor of neurology at UC Irvine School of Medicine.
"Even more intriguing, the use of blood pressure-lowering medication in this 90-plus group was linked to a lower likelihood of specific types of brain damage."
Team members, which also included UCI Health neurologist Dr. Claudia Kawas, analyzed the relationship between cardiovascular-related changes in the brain and self-reported vascular risk factors or use of heart-related medications by examining data from 267 participants in the National Institute on Aging's 90+ Study, one of the largest and most comprehensive research projects on the oldest-old population.
They applied statistical models that accounted for age, sex and education and found that the presence of brain changes was not linked to traditional risk factors like high blood pressure or diabetes.
In addition, they discovered that certain medications showed potential proactive effects. Diuretics were linked to a lower likelihood of atherosclerosis, commonly called "hardening of the arteries," and beta blockers and vasodilators were associated with reduced odds of cerebral amyloid angiopathy, the buildup of a type of protein in brain blood vessels.
"Our findings challenge the idea that traditional vascular risk factors are always harmful to brain health in the 90-plus population," Rajmohan said. "Our findings may reflect the effectiveness of treatment for those conditions, or they could be influenced by survival bias, as individuals with untreated or severe risk factors may not live into their 90s. Further research is needed to explore whether blood pressure-lowering medications could directly reduce the risk of brain blood vessel damage and dementia under specific circumstances. Such knowledge could lead to more personalized advice for managing blood pressure and improving brain health outcomes."
Team members also included Maria Corrada, professor in residence of neurology; Annlia Paganini Hill, project scientist in neurology; and biochemistry graduate student Joey Wong - all from UC Irvine - as well as Dr. Thomas Montine, chair pathology at Stanford University; Zeinah Al-Darsani, epidemiology and biostatistics graduate student at Temple University's College of Public Health; and Chu-Ching Ho, computer science graduate student at the University of Illinois Urbana-Champaign.
This work was supported by the National Institute on Aging under grant AG021055 and the Alzheimer's Disease Research Consortium under grant P30AGO66519.
About UCI Health
UCI Health, one of California's largest academic health systems, is the clinical enterprise of the University of California, Irvine. The 1,317-bed system comprises its main campus UCI Medical Center, an acute care hospital in Orange, Calif., the UCI Health - Irvine medical campus, four hospitals and affiliated physicians of the UCI Health Community Network in Orange and Los Angeles counties and ambulatory care centers across the region. Recognized as a Top Hospital by The Leapfrog Group, UCI Medical Center provides tertiary and quaternary care and is home to Orange County's only National Cancer Institute-designated comprehensive cancer center, high-risk perinatal/neonatal program and American College of Surgeons-verified Level I adult and Level II pediatric trauma center, gold level 1 geriatric emergency department and regional burn center. UCI Health serves a region of nearly 4 million people in Orange County, western Riverside County and southeast Los Angeles County. Follow us on Facebook, Instagram, LinkedIn and Twitter.