Multiple sclerosis (MS) patients with elevated levels of nerve biomarker NfL in their blood are at an increased risk of worsening disability within two years, new research led by UC San Francisco suggests.
The study is the first to establish a timeframe for a decline in health following? injury to the central nervous system.
More than 130,000 people in the UK live with MS, with many experiencing limited mobility, weakness, spasticity, poor co-ordination and incontinence.
However, more severe symptoms could potentially be substantially delayed or prevented altogether with new treatments.
In the study, researchers looked at the incidence of disability worsening which is defined as at least six months of increased impairment according to the Expanded Disability Status Scale.
The researchers tracked data of approximately 4,000 UCSF patient spanning 10 years and approximately 9,000 patient visits to various sites in Switzerland.
The two studies comprised almost 1,9000 patients over all of which 570 were identified as having a disability that continued to worsen, most of which were independent of relapses.
The researchers discovered that elevated NfL levels were associated with up to a 91 per cent higher risk of worsening disability with relapse approximately a year later, and up to a 49 per cent higher risk of worsening disability without relapse nearly two years later.
Abdelhak said: “We think that NfL elevation occurs earlier in disability worsening without relapse.”
This different pattern may indicate “a more prolonged process that decreases in intensity in advance of increased impairment,” said co-senior author Ari Green, MD, medical director of the UCSF Multiple Sclerosis and Neuroinflammation Center.
“This aligns with recognition that death of nerve cells is a slow process that builds toward permanent disability and means that interventions to protect nerve cells might have time to also stop disability,” he added.
Co-senior author Jens Kuhle, MD, PhD, said: “In addition to the ground-breaking findings on the temporal relationship between NfL increases and gradual disease progression in MS, the study supports the important role of NfL as an early marker of nerve damage.
“Monitoring NfL levels might be able to detect disease activity with higher sensitivity than clinical exam or conventional imaging,” he said.
The researchers will now explore potential therapies that can stop progression during this period of elevated NfL.
