In a study published today [Friday, 13th February 2026] in the journal Nature Aging researchers show that blood-based biomarkers can support accurate dementia diagnosis across diverse populations when integrated with cognitive and neuroimaging measures.
Blood-based biomarkers are emerging as one of the most promising advances for the global diagnosis of dementia, including Alzheimer's disease and frontotemporal lobar degeneration. These tests offer a more accessible, scalable, and cost-effective alternative to traditional diagnostic tools such as brain imaging or cerebrospinal fluid analysis. However, most blood-based biomarkers have been developed and validated primarily in relatively homogeneous populations . Genetic background, overall physical health, and environmental and social exposures can substantially influence biomarker levels, raising concerns about how well these tests perform across diverse populations worldwide.
To address this critical gap, an international multicenter study evaluated blood-based biomarkers in a highly diverse population from Latin America, encompassing wide genetic admixture, racial diversity, and environmental variability. The study demonstrates that key plasma biomarkers can reliably distinguish major dementia syndromes even in complex and heterogeneous real-world settings, particularly when combined with clinical and cognitive assessments.
"These findings reinforce the enormous potential of blood-based tests to transform dementia diagnosis," said Claudia Duran-Aniotz, senior author of the study, director of BrainLat and Global Brain Health Institute (GBHI) fellow at Trinity College Dublin. "But they also show that diversity cannot be an afterthought—biomarkers must be tested and validated in populations that reflect the real world."
The study examined blood-based biomarkers for dementia in 605 participants recruited across six countries, representing substantial genetic, racial, and environmental diversity. Using key plasma biomarkers within the AT(N) framework—amyloid-β (Aβ42/Aβ40), phosphorylated tau (p-tau217, p-tau181), and neurofilament light chain (NfL)—the study showed that blood-based measures can reliably distinguish Alzheimer's disease and frontotemporal lobar degeneration from cognitively normal individuals. Biomarker alterations were consistently associated with domain-specific cognitive impairment and disease-relevant patterns of brain atrophy and functional connectivity.
While blood biomarkers alone achieved good diagnostic accuracy, performance improved markedly when combined with cognitive assessments and neuroimaging, underscoring that robust and equitable dementia diagnosis requires integrating biological, cognitive, and brain-based measures. The results highlight the importance of moving beyond one-size-fits-all approaches and ensuring that emerging diagnostic technologies are robust, equitable, and globally applicable.
"Combining biomarkers with cognitive and neuroimaging markers in diverse populations is essential to avoid misdiagnosis and to ensure fair access to care," said Agustin Ibanez, co-senior author of the study and researcher at GBHI and BrainLat. "Otherwise, even the most advanced tools risk reinforcing existing health inequalities." By demonstrating consistent performance across genetically and environmentally diverse groups, the study provides a key step toward more inclusive and precise dementia diagnostics. "This work shows that blood-based biomarkers can work across complexity—but only when diversity is explicitly built into the science," said Ariel Caviedes, first author of the paper. "That is crucial for the future of global brain health." added Felipe Cabral, co-first author of the study.
READ: Link to the publication, once the paper has been published at 10am Friday 13th February 2026, can be found at this link: https://www.nature.com/articles/s43587-025-01061-3
