A vascular signal in an Alzheimer’s risk study
Researchers at Rutgers-Newark have reported an association between arterial stiffness and an early Alzheimer’s disease biomarker in older adults carrying a specific genetic variant linked to people of African descent. The finding points to vascular health as a potentially important area of attention for people who test positive for the variant, though the study does not establish that improving blood-vessel health will prevent Alzheimer’s disease.
The work focused on a variant called ABCA7-80. In the study, participants with that variant showed a stronger relationship between stiffer arteries and higher blood levels of p-tau, an abnormal protein associated with the very early stages of Alzheimer’s disease. P-tau can be detected before dementia or measurable cognitive impairment emerge.
Mark Gluck, a Rutgers professor of neuroscience and public health who directs the Aging & Brain Health Alliance, said the result suggests that maintaining healthy blood vessels may be especially important for people who screen positive for this genetic risk factor. The research was published in Alzheimer’s & Dementia: Translational Research & Clinical Interventions.
What the team measured
The researchers enrolled 143 participants, all aged 60 or older and cognitively healthy. They collected blood and saliva samples, measured blood pressure and used a specialized MRI-based method to assess how quickly blood travels through arteries. Those data were used to characterize each participant’s genetics, vascular condition and p-tau level.
Arteries naturally tend to become less flexible with age. This stiffening can affect how blood moves through the body and may influence the brain. The Rutgers analysis found that, among carriers of ABCA7-80, less-flexible blood vessels were associated with higher concentrations of p-tau. The source material describes ABCA7-80 as unique to people of African descent.
That population context matters. The researchers note that African Americans are more than twice as likely to develop Alzheimer’s disease as other groups. A better understanding of risk factors that are particularly relevant to this population could help shape future prevention research and more targeted health strategies.
An association, not a diagnosis or cure
The study’s result is an observed link in a group of cognitively healthy older adults. It does not mean that a person with the ABCA7-80 variant will develop Alzheimer’s disease, nor does it show that arterial stiffness causes a rise in p-tau. It also does not demonstrate that changing vascular health will lower a person’s Alzheimer’s risk.
Still, the result gives researchers a concrete interaction to investigate: a genetic factor alongside a potentially modifiable feature of cardiovascular health. Miray Budak, the study’s lead author and a postdoctoral fellow in aging neuroscience at Rutgers-Newark, said poor vascular health can have negative effects on the brain. The work adds evidence that those effects may differ across genetic backgrounds.
The next questions are likely to be longitudinal ones. Researchers will need to determine whether the relationship holds in larger and more diverse groups, whether it persists over time and whether vascular interventions change biomarker trajectories. The present study offers a reason to ask those questions, rather than an answer to them.
Why prevention research may benefit from precision
Alzheimer’s research increasingly examines changes that occur years before symptoms. Blood-based biomarkers such as p-tau make it possible to study some of those changes without waiting for dementia to appear. Pairing those measures with genetics and vascular assessments may help researchers identify combinations of risk that a one-size-fits-all approach could miss.
For now, the Rutgers team’s result is best understood as a signal: in this cohort, the combination of ABCA7-80 and arterial stiffness tracked with a biomarker of early Alzheimer’s-related disease processes. It reinforces the case for studying brain health and cardiovascular health together, while underscoring the need for research that includes populations whose genetic risks have often received less specific attention.
This article is based on reporting by Medical Xpress. Read the original article.
Originally published on medicalxpress.com
