AI Insight
This systematic review and meta-analysis examined 168 publications across 139 independent cohorts from six continents to evaluate blood-based biomarkers for Alzheimer's disease (AD) across diverse ethnoracial populations. The biomarkers p-tau217, p-tau181, and glial fibrillary acidic protein (GFAP) demonstrated the largest and most consistent differences between AD patients and cognitively unimpaired individuals. Notably, some population-level differences emerged in clinically defined comparisons — p-tau181 showed lower separation in predominantly Asian versus White cohorts for mild cognitive impairment, while GFAP showed higher separation in AD for Asian cohorts — though no significant between-population differences appeared in amyloid PET-defined comparisons.
Why it matters
Blood-based biomarkers offer a scalable, less invasive alternative to PET imaging and cerebrospinal fluid testing for AD detection, but this study highlights that current diagnostic thresholds may not translate equitably across all populations, underscoring the urgent need for harmonized, globally representative validation studies before widespread clinical deployment.
⚠️ Preprint – Noch nicht peer-reviewed
Dieser Artikel wurde noch nicht von unabhängigen Experten begutachtet. Die Ergebnisse sind vorläufig und sollten mit Vorsicht interpretiert werden.
Blood-based biomarkers could transform Alzheimer disease (AD) detection by enabling scalable, less invasive assessment of underlying pathology, yet their applicability across globally diverse populations remains uncertain. We systematically reviewed 168 publications comprising 139 independent cohorts from Asia, Europe, North America, South America, Africa and Oceania. Random-effects meta-analyses pooled log-transformed ratios of mean biomarker concentrations for AD versus cognitively unimpaired individuals, mild cognitive impairment versus cognitively unimpaired individuals, and amyloid-{beta} PET-positive versus amyloid-{beta} PET-negative individuals. p-tau217, p-tau181 and glial fibrillary acidic protein showed the largest and most consistent group differences. In clinically defined comparisons, p-tau181 separation in mild cognitive impairment was lower in predominantly Asian than White cohorts, whereas glial fibrillary acidic protein separation in AD was higher in predominantly Asian cohorts. No significant between-population differences were observed in amyloid-defined comparisons. These findings support leading blood biomarkers as globally relevant indicators of AD pathology, but rigorous harmonized validation is needed before thresholds can be translated into equitable clinical practice.