A recent study utilizing data from the Alzheimer’s Disease Neuroimaging Initiative (ADNI) and the A4 studies reveals significant challenges in substituting blood-based biomarkers for Alzheimer’s disease (AD) pathology, specifically p-tau 181 and p-tau 217, in place of amyloid-PET Centiloids. While blood-based biomarkers offer advantages such as lower costs and ease of collection, the research shows that their use can substantially reduce statistical power, requiring 1.5 to 6.5 times larger sample sizes to achieve comparable power levels.

Moreover, using blood-based biomarkers as exposures may introduce regression dilution bias, potentially skewing the associations drawn from studies. These findings underscore the importance of carefully considering the methodological implications when designing studies that incorporate blood-based measures.

For longevity and healthspan researchers, this study highlights the necessity of balancing the practical benefits of blood-based biomarkers with their limitations, ensuring robust study designs that account for sample size and bias to maintain the integrity of research outcomes.

Source: academic.oup.com