The current landscape of prospective proteomics research into dementia using blood-based samples.

PURPOSE OF REVIEW: Well conducted, prospective, blood-based biomarker studies on dementia risk are growing, providing valuable insights into disease mechanisms that precede clinical symptoms. These investigations are crucial for advancing our understanding of dementia pathology and identifying early biological changes.

RECENT FINDINGS: Emerging evidence shows that proteins detected in peripheral tissues and the circulatory system can also play a role in neurological diseases. Both neuronal and nonbrain-specific proteins have been associated with dementia prior to symptom onset, highlighting the complex and multisystem nature of disease development. Of the 11 studies included in this review that focused on prospective studies of dementia that applied plasma proteomics, 36 proteins were identified in at least two independent cohorts, suggesting that blood-based proteomics detects consistent protein levels that may be altered years before dementia diagnosis.

SUMMARY: Blood-based biomarkers hold promise for early diagnosis, patient stratification, and mechanistic research in dementia. The observed overlap in protein profiles across studies suggests we are beginning to uncover systemic biological differences that contribute to disease progression.