Multiple sclerosis (MS) is an autoimmune disease in which the immune system attacks the central nervous system, causing demyelination of white matter and making the transmission of signals between the brain and the body difficult. Nearly one million Americans suffer from MS. In advanced cases, patients may experience restricted mobility, spasms, weakness, poor coordination, and incontinence. Timely diagnosis and monitoring treatment progress are crucial needs in caring for patients, but currently, there is still a lack of comparably accurate and timely tools.
And now, fluid biomarkers may help unravel the complex interactions between neurons, glial cells, and immune cells, thereby providing predictions for disease progression. Neurofilament light chain (NfL) is a neuron-specific protein released into the cerebrospinal fluid and blood, and NfL has become a leading biomarker for detecting neuronal damage. Its concentration is high in the blood of patients with axonal injuries.
According to a new study led by researchers from the University of California, San Francisco, blood tests in multiple sclerosis (MS) patients indicate an elevated level of NfL, and once detected, there may be confirmed disability worsening (CDW) one to two years later. This study quantifies, for the first time, the timeframe of disability worsening following central nervous system damage.
In this study, researchers tracked data from approximately 4,000 patients seen at UCSF over a 10-year period (including the EPIC study) and about 9,000 patients seen at various locations in Switzerland (including the SMSC study). These two studies collectively included nearly 1,900 patients, with 570 patients identified as having sustained worsening disability, most of whom did not experience relapses.
The researchers found that an increase in NfL levels was highly correlated with a 91% increased risk of disability worsening and relapse approximately one year later, and a 49% increased risk of disability worsening without relapse nearly two years later.
The elevation of NfL occurs in the early stages of disability worsening without relapse, aligning with the perspective that neuronal cell death is a slow process ultimately leading to permanent disability. This suggests that interventions to protect neuronal cells may have time to prevent disability. In addition to the groundbreaking discovery regarding the timing relationship between NfL increase and the gradual progression of MS, the study also supports the crucial role of NfL as an early biomarker for neural damage. Monitoring NfL levels may offer higher sensitivity in detecting disease activity compared to clinical examinations or traditional imaging.
Future research will explore therapeutic approaches that can halt progression during the period of NfL elevation.
