Abstract

Alzheimer’s disease (AD), the leading cause of dementia, is an age-related neurodegenerative disorder characterized by the accumulation of amyloid-beta peptides and tau proteins in the brain. With Alzheimer’s growing at unprecedented rates, now more than ever before, the medical arsenal cries out for diagnostic screening interventions to catch the neurodevelopment process in its tracts. Tear fluid, although underexplored, offers a minimally invasive, cost-effective alternative for early detection of AD, at reflects systemic changes linked to neurodegenerative processes, shining light on AD’s “biochemical footprint “. This systematic review examines the presence of tear biomarkers and compares their concentrations among healthy individuals, those with mild cognitive impairment (MCI), and AD patients. Key findings reveal specific biomarkers, such as dermicidin and MicroRNA-200b-5p, which demonstrate sensitivity and specificity for AD. Furthermore, AD patients exhibit increased tear flow rates and elevated protein concentrations. Our findings may be play a role in shifting the research attention towards the viability of tears as a candidate for AD diagnosis, with our research suggesting them to be a promising reservoir for early detection of AD and future biomarker discovery.