Better Cardiovascular Health May Stave Off Degenerative Brain Disease

Older adults who have the best cardiovascular health also appear to carry lower risks for developing neurodegenerative disease, according to an analysis of the Chicago Health and Aging Project (CHAP).

A higher cardiovascular health score according to the American Heart Association’s Life’s Simple 7 tool was associated with significantly lower serum levels of neurofilament light chain (NfL), a marker of axonal damage and neurodegeneration, in adults 65 years or older.

The findings, published online this week in JAMA Network Open, “align with other research on CV health and neurodegenerative disease,” lead author Anisa Dhana, MD (Rush University Medical Center, Chicago, IL), told TCTMD via email. “Encouraging heart-healthy behaviors like maintaining normal blood pressure, regular exercise, and a balanced diet could slow cognitive decline and lower the risk of dementia.”

Commenting for TCTMD, Anum Saeed, MD (University of Pittsburgh School of Medicine, PA), said it has become clear over the years that cardiovascular disease and its risk factors have associations with neurological outcomes, including stroke and dementia, and this new study adds to the growing literature demonstrating a heart-brain connection.

Saeed noted that her team published a study earlier this year showing a link between midlife cardiovascular risk and late-life neurodegeneration. “I think we as clinicians need to learn that cardiovascular risk factors don’t just impact cardiovascular disease, but they have this overall risk with all the other organs,” she said.

Simple Message for Patients

Though prior research was shown relationships between CV health and risks of Alzheimer’s disease and vascular dementia, there has been less information on links between heart health and biomarkers of neurodegeneration.

To explore the issue, Dhana and colleagues turned to CHAP, a study of risk factors for cognitive impairment, Alzheimer’s disease, and other dementias among older adults living in Chicago, IL. The current analysis included 1,018 participants (mean age 73.1 years; 61.4% women) who had information available on serum levels of NfL and total tau (t-tau) and on the components of Life’s Simple 7—healthy diet, regular exercise, normal body mass index, nonsmoking status, and management of dyslipidemia, diabetes, and hypertension. Most (60%) were Black, and the rest were white.

The cohort was divided into three groups according to their CV health scores—low (0-6 points), intermediate (7-9 points), and high (10-14 points). Those with a high score tended to be white (64.3%) and to have a higher education level (mean 13.6 years).

Compared with those with low CV health scores, those with high scores had serum NfL levels that were a relative 18.9% lower (P < 0.001) as well as a slower annual increase in NfL levels (by 1.7%; P = 0.04).

There no such associations for t-tau. Though both NfL and t-tau are biomarkers of neurodegeneration, “increased plasma levels of NfL and t-tau may be attributable to different risk factors and pathways to neurodegenerative diseases,” Dhana et al explain in their paper.

“Specifically, NfL is a marker of neuronal damage, and axonal damage has been, in part, attributed to cerebral injuries, including cerebral vascular pathology,” they continue. “Cardiovascular health comprises vascular risk factors, such as hypertension and diabetes, known to contribute to vascular damage and, consequently, compromise blood-brain barrier integrity, thereby increasing neuronal damage and elevating NfL levels.”

The study’s message for patients is simple, Saeed said.

“Know your numbers and get on top of your disease early if you have risk factors such as hypertension, diabetes, and high cholesterol,” she advised. “You need to be making sure you’re checking those numbers and you are keeping them in check. And obviously, try to maintain a healthy lifestyle, a healthy diet, and so forth.”

Though more information on social determinants of health would add another layer to this research, for now, she said, “as a clinician, I’m telling my patients that if you want a healthy brain, you should keep a healthy heart. That’s something that we can control.”

We as clinicians need to learn that cardiovascular risk factors don’t just impact cardiovascular disease. Anum Saeed

Further research is needed to examine additional biomarkers of neurodegeneration, like phosphorylated tau, and to determine how sleep quality—which was added as an eighth component of cardiovascular health for Life’s Essential 8—may influence the findings.

“There’s more of those risk factors that we need to account for as a cardiovascular community and also understand how to change these risk factors, because as we get older, most of our patients have these problems,” Saeed said. “How does that impact their risk for future dementia and neurodegeneration? I think that’s sort of a call to the research community.”