Research from the University of California, Irvine indicates that common cardiovascular issues like high blood pressure and diabetes, which typically harm brain blood vessels in younger individuals, do not appear to increase the risk of such damage in people aged 90 and above.
This study, published today in the journal Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association, implies that the links between blood pressure, vascular health, and aging of the brain are more intricate than previously believed.
“For many years, it has been understood that conditions like high blood pressure and diabetes can damage brain blood vessels, raising the likelihood of cognitive decline and dementia. However, our research suggests that these associations may evolve as individuals grow older,” stated Dr. Ravi Rajmohan, a clinical instructor of neurology at UC Irvine and corresponding author of the study. “Interestingly, we found that among those aged 90 and over, taking medication to lower blood pressure was associated with a reduced risk of certain types of brain damage.”
The research team examined the connections between cardiovascular changes in the brain and self-reported vascular risk factors, as well as the use of heart-related medications. They analyzed data from 267 participants in the National Institute on Aging’s 90+ Study, one of the largest and most comprehensive research efforts focusing on very elderly individuals. Their statistical analysis, which controlled for age, sex, and education, revealed that brain changes were not connected to classic risk factors such as high blood pressure or diabetes.
Additionally, they found that some medications might offer protective benefits. For example, diuretics were associated with a lower risk of atherosclerosis (often referred to as “hardening of the arteries”), while beta blockers and vasodilators correlated with reduced odds of cerebral amyloid angiopathy, a condition that involves the accumulation of certain proteins in the brain’s blood vessels.
“These results question the notion that traditional vascular risk factors are inevitably detrimental to brain health in the population aged 90 and older,” Rajmohan added. “Our findings may represent the effectiveness of treatments for these conditions, or they might be affected by survival bias; that is, individuals with untreated or severe risk factors might not reach their 90s. More research is necessary to determine if blood pressure-lowering medicines can directly lessen the risk of damage to brain blood vessels and dementia in specific situations. Such insights could lead to tailored recommendations for managing blood pressure and enhancing brain health outcomes.”
The research team included Dr. Claudia Kawas, professor of neurology and neurobiology & behavior; Maria Corrada, a professor in residence of neurology; Annlia Paganini Hill, project scientist in neurology; and Joey Wong, a biochemistry graduate student, all from UC Irvine. They were joined by Dr. Thomas Montine, chair of pathology at Stanford University; Zeinah Al-Darsani, an epidemiology and biostatistics graduate student at Temple University’s College of Public Health; and Chu-Ching Ho, a computer science graduate student from the University of Illinois Urbana-Champaign.
This study received support from the National Institute on Aging under grant AG021055, alongside backing from the Alzheimer’s Disease Research Consortium under grant P30AGO66519.
