EARLY BIOMARKERS FOR ALZHEIMER’S DISEASE PROGRESSION: A LONGITUDINAL CLINICAL STUDY

Abstract

Background

Alzheimer’s disease progression from mild cognitive impairment (MCI) remains challenging to predict. Biomarkers like CSF Aβ42,tau proteins, plasma NfL, and MRI-based atrophy identify rapidly.

Methodology

It was a prospective cohort study. Following informed consent, 40 patients with early-stage Alzheimer’’s disease diagnosed using NIA-AA criteria were included. P2, total patients aged 55 to 80 years were included in the study. Presence of other neurodegenerative disorders such as Parkinson’s disease was excluded. Participants were evaluated at baseline, 6^th-month. Blood samples were analysed for plasma Aβ42, total tau and NfL. Cognitive function was assessed using MMSE and ADAS-Cog, whereas hippocampal atrophy was assessed using MRI.

Results

Plasma Aβ42 levels fell by 13.4%, whereas total tau rose by 17.2%, indicating amyloid builup and neuronal damage. Cognitive scores decreased considerably after 6^th- month (MMSE: -3.2; ADAS-Cog: +8.4; p<0.001). There was a strong association between increased NfL levels and cognitive deterioration (MMSE: r=-0.60; ADAS-Cog: r=0.56). NfL emerged as the most sensitive biomarker of neurodegeneration throughout the early stages of AD progression.

Conclusion

This study found that plasma levels of Aβ42, total tau, and NfL are associated to cognitive impairment over 6 month. Among these, NfL had the highest association with disease progression indicating that it might be a viable early biomarker for monitoring AD.