BBRC researchers take part in a Nature Aging study validating blood biomarkers in diverse populations

Blood-based biomarkers research is reshaping the landscape of dementia diagnosis. Compared with more complex and costly techniques, such as PET imaging or cerebrospinal fluid analysis, blood tests open the door to tools that are more accessible and scalable, with particularly high potential in regions where access to specialised infrastructure is limited.

In this context, a multicentre study published in Nature Aging provides pivotal evidence. Its aim is to tackle a priority challenge for the scientific community: confirming that these biomarkers remain reliable beyond traditional cohorts, which have largely been European and North American. This is essential to ensure clinical applicability in diverse populations.

Co-led by Dr Agustín Ibáñez, a BBRC collaborator and corresponding author, and Dr Claudia Duran-Aniotz, the study includes participation from Dr Marta del Campo, Director of the BBRC Fluid Biomarker Facility, and Dr Marc Suárez-Calvet, group leader of the Fluid Biomarkers and Translational Neurology research group. The team assessed plasma biomarkers in 605 participants from six Latin American countries, incorporating wide genetic, environmental, and sociocultural variability.

Validating the model using a blood sample

The research is based on the AT(N) framework, a system that organises biomarkers according to three major biological processes involved in Alzheimer’s disease: “A” refers to amyloid-β markers, “T” to tau pathology markers, and “(N)” to markers of neurodegeneration or neuronal injury.

In this study, the authors evaluated blood biomarkers aligned with this model, including the Aβ42/Aβ40 ratio, phosphorylated tau (p-tau217 and p-tau181), and neurofilament light chain (NfL). The results show that these markers are consistently associated with cognitive impairment and with brain changes relevant to the disease, even when comparing populations across different countries. In addition, the researchers observed that accuracy improves when blood-based biomarkers are combined with cognitive tests and, when possible, with neuroimaging techniques.

Advances in blood biomarkers make it possible to apply this same diagnostic approach using a simple blood sample, facilitating implementation and broadening potential clinical use, especially in settings with fewer specialised resources.

Diversity and equity: a strategic priority for BBRC

Beyond the clinical findings, the study reinforces a key message for international research: validating biomarkers in diverse populations is not only a methodological concern, but a requirement to avoid bias, calibrate cut-offs, and ensure equity in access to future diagnostic and therapeutic tools.

Advancing towards a future without Alzheimer’s demands international collaboration, rigorous validation, and diversity in study cohorts. “Studies like this broaden the reach of scientific knowledge and consolidate BBRC’s role as a leading centre in blood biomarker research for the early diagnosis of Alzheimer’s disease,” explains Dr Agustín Ibáñez, BBRC collaborator.

This approach directly connects with the Barcelonaβeta Brain Research Center’s strategy, which promotes research aimed at ensuring scientific advances are robust, reproducible, and applicable in real-world practice, especially in the early stages of the disease.

Building on this approach, DIV-AD is a BBRC-led project that seeks to validate blood-based Alzheimer’s biomarkers in diverse communities that have historically been under-represented in biomedical research. Its goal is to build more inclusive evidence and ensure diagnostic advances maintain their accuracy across different population contexts.

Reference article:

Caviedes, A., Cabral-Miranda, F., Orellana, P. et al. Blood-based AT(N) biomarkers for Alzheimer’s disease and frontotemporal lobar degeneration in Latin America. Nat Aging (2026). https://doi.org/10.1038/s43587-025-01061-3