Clarifying blood-based brain-derived neurotrophic factor measurement in Alzheimer's disease research: A call for pre-analytic standardization.

The study by Kueck et al. rigorously addresses the complex pre-analytical and biological confounds underlying blood-based brain-derived neurotrophic factor (BDNF) measurement in Alzheimer's disease (AD) research. By directly comparing platelet-rich plasma and platelet-poor plasma, it distinguishes free-circulating from platelet-stored BDNF and their associations with core AD biomarkers. Findings support BDNF as a potential compensatory marker in early cognitive impairment and emphasize the critical need for biomarker-specific pre-analytic standardization protocols. This commentary contextualizes the work within existing inconsistencies and outlines key recommendations for standardizing blood-based BDNF measurements to ensure reproducibility, potential clinical utility, and translational relevance.