The National Institutes of Health announced NIH-funded research showing that elevated circular RNAs in blood nearly tripled patients’ risk of developing Alzheimer’s disease symptoms, based on analysis of more than 1,200 people across multiple cohorts.
The study is focused on whether blood-based circular RNAs could help predict Alzheimer’s symptom onset, rather than only detect disease markers. NIH said the findings may support future clinical trial selection, treatment monitoring and development of blood-based assays.
Alzheimer’s Blood Test Research Identifies New Biomarker
NIH said small loops of genetic material known as circular RNAs may be strong indicators of approaching Alzheimer’s disease symptoms. In the NIH-funded study, researchers found that elevated levels of certain circRNAs in blood nearly tripled patients’ risk of developing symptoms.
The finding could support future blood-based tests that identify people closer to cognitive decline, rather than only confirming disease pathology. However, NIH described the work as groundwork for potential assay development, not as a currently available clinical tool.
Alzheimer’s Biomarker Findings
| Indicator | Recent Movement | Context |
|---|---|---|
| Study size | More than 1,200 people | NIH reported multiple independent cohorts |
| Risk signal | Nearly tripled risk | NIH linked elevated circRNAs to symptoms |
| Biomarker set | 34 circRNAs | Researchers associated them with Alzheimer’s disease |
Current Blood Tests Detect Disease But Not Progression
NIH said current Alzheimer’s blood tests can reliably support diagnosis by detecting markers of amyloid plaques, a hallmark of the disease. However, NIH noted that these tests can produce positive results potentially decades before cognitive impairment and may not show how a patient’s condition will progress.
The study separates diagnosis from prediction by focusing on whether blood markers can indicate when symptoms may begin. Additionally, the study’s focus on progression may help researchers assess who is approaching symptom onset, while keeping the evidence tied to measured biomarkers.
Stakeholder Comments
Richard Hodes, M.D., Director of NIH’s National Institute on Aging said;
“In a clinical setting, being able to identify patients on the verge of symptom onset would be invaluable. Having this information could help us select the right patients for clinical trials and better determine which treatments are effective at preventing cognitive decline.”
Carlos Cruchaga, Ph.D., Washington University School of Medicine, St. Louis said;
“Patients being treated with novel Aβ-removal therapies, can become pTau negative but still have Alzheimer’s disease. These circular RNAs may grant us a more complete perspective of someone’s overall disease biology.”
“It’s nice to have good science and models, but we’re ultimately doing this to help people.”
Circular RNAs Reflect More Recent Brain Activity
NIH said circRNAs differ from amyloid plaques because they are more dynamic and reflect more recent brain activity. Earlier work by Carlos Cruchaga and colleagues at Washington University School of Medicine linked circRNAs in the brain to dementia and neuropathological severity.
The new study tested whether those associations were also visible in blood, which NIH described as a more accessible tissue. Meanwhile, researchers found that a model based on 34 circRNAs performed similarly to pTau217 models for identifying Alzheimer’s pathology, but performed better at predicting future symptomatic progression.
- Progression signal: NIH said circRNA levels appeared to diverge from normal about two to four years before symptom onset.
- Comparison point: NIH described pTau217 as the leading clinical blood-based biomarker for Alzheimer’s disease.
- Clinical direction: NIH said researchers and commercial partners are working on translatable blood-based circRNA assays.
The NIH-funded findings place circular RNAs within a developing field of Alzheimer’s blood-test research focused on disease progression. The study reported a 34-circRNA model, more than 1,200 participants and a stronger prediction signal for symptom onset than pTau217, while NIH framed the work as a basis for future clinical assays rather than an approved diagnostic product.
Sources: National Institutes of Health, National Institute on Aging, NIH.
Prepared by Ivan Alexander Golden, Founder of THX News, an independent news organization delivering timely insights from global official sources.
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