Alzheimers Dementia: Neurofilament light chain protein in the blood, which can effectively predict cognitive decline

Biomarkers for Alzheimer's disease (AD) can help describe the existence and severity of the disease and monitor the effect of disease-modulating treatments.
Blood-based measurement methods have many advantages, including minimally invasive, cost-effective and feasible in different environments.
Nerve filaments (NFs) are a structural component of nerve cytoskeleton, which exist in dendrites and perinuclear, and are especially abundant in axons.
Given that any pathological process that leads to neuron death or axon damage will lead to the release of NF protein into the extracellular fluid, the increase in the concentration of NF protein in biological fluids is not unique to a certain disease, but represents neurodegeneration.
General indicators.
NFs have subunits (heavy, moderate, and mild), and most studies on neurodegenerative diseases have focused on the light subunit (NFL).
However, few studies have examined the relationship between NFL and neuropsychological performance, and the relationship between NFL and longitudinal cognitive decline remains unclear.

In the preclinical stage of AD, sensitive neuropsychological measures can be used to capture subtle objective cognitive changes.
These measures have more prognostic value than traditional AD biomarkers in predicting decline.
Neuropsychological process scores (Process scores) quantify the number and types of errors that a person makes in neuropsychological tests, or the methods used in a task, and are different from the traditionally used total scores.

Process scores have been used to detect cognitive inefficiencies before the onset of dementia.
Previous work used process scores to classify objectively-defined subtle cognitive decline (Obj-SCD), showing the cerebrospinal fluid (CSF) and positron emission tomography (PET) AD biology of Obj-SCD participants Marker abnormalities are between participants with normal cognition (CN) and mild cognitive impairment (MCI), which suggests that Obj-SCD can be detected at the same time as the pathological accumulation of amyloid and tau.
However, the relationship between Obj-SCD status and blood biomarkers including plasma NFL is unclear.

In this way, Katherine J.
Bangen of the University of California San Diego and others studied whether individuals with Obj-SCD exhibit a cross-sectional increase in plasma NFL, and whether baseline plasma NFL can predict the trajectory of cognition.

They used a cohort from the Alzheimer's Disease Neuroimaging Initiative (ADNI), in which 294 participants received a baseline blood draw and a 5-year continuous neuropsychological test.

They found that people with Obj-SCD and MCI showed elevated baseline plasma NFL relative to the cognition normal (CN) group.
Throughout the sample, the increase in the NFL heralds a faster rate of cognitive and functional decline.

In the Obj-SCD and MCI groups, compared with the CN group, higher NFL levels predicted a faster decline in memory and preclinical AD composite scores.

The important significance of this research lies in the discovery of the utility of plasma NFL as a biomarker of early AD-related changes and provides support for the use of Obj-SCD standards in clinical research to better capture subtle cognitive changes.

Original Source: Bangen, KJ, Thomas, KR, Weigand, AJ, Edmonds, EC, Clark, AL, Solders, S.