Dataset Information

Association of Serum Neurofilament Light Levels With Long-term Brain Atrophy in Patients With a First Multiple Sclerosis Episode.

ABSTRACT:

Importance

Data are needed on the potential long-term prognostic association of serum neurofilament light in multiple sclerosis (MS).

Objective

To evaluate serum neurofilament light as a biomarker associated with long-term disease outcomes in clinically isolated syndrome.

Design, setting, and participants

This post hoc cohort study used data from the Controlled High-Risk Avonex Multiple Sclerosis Prevention Study, a 36-month, multicenter, placebo-controlled interferon β-1a randomized clinical trial conducted from April 1996 to March 2000, and its long-term (5- and 10-year) extension study from February 2001 to March 2009. Participants included individuals with a symptomatic initial demyelinating event and brain magnetic resonance imaging (MRI) lesions suggestive of MS. Data were analyzed from April 2017 through 2019.

Exposure

The variable of interest was naturally occurring serum neurofilament light concentration.

Main outcomes and measures

Gadolinium-enhancing (Gd+) lesion number, T2 lesion volume, and brain parenchymal fraction, a measure of brain atrophy were measured at baseline and 5 and 10 years. Multivariate regression models evaluated whether age, sex, and baseline covariates, including serum neurofilament light, brain parenchymal fraction, Expanded Disability Status Scale, Gd+ lesion count, and T2 lesion volume, were associated with brain parenchymal fraction changes over 5 and 10 years.

Results

Among 308 included participants (mean [SD] age, 33.2 [7.6] years; 234 [76.0%] women), baseline serum neurofilament light concentrations were associated with Gd+ lesions (Spearman r = 0.41; P < .001) and T2 lesion volume (Spearman r = 0.42; P < .001). Among covariates for brain parenchymal fraction change, serum neurofilament light concentration had the greatest correlation with change in brain parenchymal fraction at 5 years (Spearman r = -0.38; P < .001) and was the only variable associated with brain parenchymal fraction at 10 years (Spearman r = -0.45; P < .001). Participants in the highest vs lowest baseline serum neurofilament light tertiles showed brain parenchymal fraction reduction at 5 years (-1.83% [95% CI, -1.49% to -2.18%] vs -0.95% [95% CI, -0.78% to -1.12%]; P < .001) and 10 years (-3.54% [95% CI, -2.90% to -4.17%] vs -1.90% [95% CI, -1.43% to -2.37%]; P < .001). At 5 years, 6 of 45 participants (13.3%) in the highest neurofilament tertile and 2 of 52 participants (3.8%) in the lowest neurofilament tertile achieved an Expanded Disability Status Scale score of 3.5 or greater.

Conclusions and relevance

This cohort study found that higher baseline serum neurofilament light levels were associated with increased brain atrophy over 5 and 10 years. These findings suggest that serum neurofilament light could be a biomarker associated with disease severity stratification in early MS and may help to guide intervention.

SUBMITTER: Plavina T

PROVIDER: S-EPMC7645699 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Similar Datasets

Project description:ImportanceUnrecognized demyelinating events often precede the clinical onset of multiple sclerosis (MS). Identification of these events at the time of occurrence would have implications for early diagnosis and the search of causal factors for the disease.ObjectiveTo assess whether serum neurofilament light chain (sNfL) levels are elevated before the clinical MS onset.Design, setting, and participantsNested case-control study among US military personnel who have serum samples stored in the US Department of Defense Serum Repository. Serum samples were collected from 2000 to 2011; sNfL assays and data analyses were performed from 2018 to 2019. We selected 60 case patients with MS who either had 2 samples collected before onset (mean follow-up, 6.3 years) or 1 sample collected before and 1 after onset (mean follow-up, 1.3 years), among 245 previously identified case patients. For each case, we randomly selected 1 of 2 previously identified control individuals matched by age, sex, race/ethnicity, and dates of sample collection. The sample size was chosen based on the available funding.ExposuresSerum NfL concentrations measured using an ultrasensitive single-molecule array assay (Simoa).Main outcomes and measurementsLog-transformed sNfL concentrations in case patients and control individuals compared using conditional logistic regression and linear mixed models.ResultsMean age at baseline was 27.5 years, and 92 of 120 participants (76.7%) were men. Serum NfL levels were higher in case patients with MS compared with their matched control individuals in samples drawn a median of 6 years (range, 4-10 years) before the clinical onset (median, 16.7 pg/mL; interquartile range [IQR], 12.6-23.1 pg/mL vs 15.2 pg/m; IQR, 10.3-19.9 pg/mL; P = .04). This difference increased with decreasing time to the case clinical onset (estimated coefficient for interaction with time = 0.063; P = .008). A within-person increase in presymptomatic sNfL levels was associated with higher MS risk (rate ratio for ≥5 pg/mL increase, 7.50; 95% CI, 1.72-32.80). The clinical onset was associated with a marked increase in sNfL levels (median, 25.0; IQR, 17.1-41.3 vs 45.1; IQR, 27.0-102.7 pg/mL for presymptomatic and postonset MS samples; P = .009).Conclusions and relevanceThe levels of sNfL were increased 6 years before the clinical MS onset, indicating that MS may have a prodromal phase lasting several years and that neuroaxonal damage occurs already during this phase.

Project description:ImportanceBlood sample-based biomarkers that are associated with clinically meaningful outcomes for patients with multiple sclerosis (MS) have not been developed.ObjectiveTo evaluate the potential of serum neurofilament light chain (sNFL) measurements as a biomarker of disease activity and progression in a longitudinal MS data set.Design, setting, and participantsSingle-center, ongoing, prospective observational cohort study of 607 patients with MS from the longitudinal EPIC (Expression, Proteomics, Imaging, Clinical) study at the University of California, San Francisco from July 1, 2004, through August 31, 2017. Clinical evaluations and sample collection were performed annually for 5 years, then at different time points for up to 12 years, with a median follow-up duration of 10 (interquartile range, 7-11) years. Serum NFL levels were measured using a sensitive single molecule array platform and compared with clinical and magnetic resonance imaging variables with the use of univariable and multivariable analyses.Main outcomes and measuresThe main outcomes were disability progression defined as clinically significant worsening on the Expanded Disability Status Scale (EDSS) score and brain fraction atrophy.ResultsMean (SD) age of the 607 study participants at study entry was 42.5 (9.8) years; 423 (69.7%) were women; and all participants were of non-Hispanic European descent. Of 3911 samples sequentially collected, 3904 passed quality control for quantification of sNFL. Baseline sNFL levels showed significant associations with EDSS score (β, 1.080; 95% CI, 1.047-1.114; P < .001), MS subtype (β, 1.478; 95% CI, 1.279-1.707; P < .001), and treatment status (β, 1.120; 95% CI, 1.007-1.245; P = .04). A significant interaction between EDSS worsening and change in levels of sNFL over time was found (β, 1.015; 95% CI, 1.007-1.023; P < .001). Baseline sNFL levels alone were associated with approximately 11.6% of the variance in brain fraction atrophy at year 10. In a multivariable analysis that considered sex, age, and disease duration, baseline sNFL levels were associated with 18.0% of the variance in brain fraction atrophy at year 10. After 5 years' follow-up, active treatment was associated with lower levels of sNFL, with high-potency treatments associated with the greater decreases in sNFL levels compared with platform therapies (high-potency vs untreated: β, 0.946; 95% CI, 0.915-0.976; P < .001; high-potency vs platform: β, 0.972; 95% CI, 0.948-0.998; P = .04).Conclusions and relevanceThis study found that statistically significant associations of sNFL with relevant clinical and neuroimaging outcomes in MS were confirmed and extended, supporting the potential of sNFL as an objective surrogate of ongoing MS disease activity. In this data set of patients with MS who received early treatment, the prognostic power of sNFL for relapse activity and long-term disability progression was limited. Further prospective studies are necessary to assess the assay's utility for decision-making in individual patients.

Project description:BackgroundAutologous haematopoietic stem cell transplantation (AHSCT) is highly effective in reducing new inflammatory activity in aggressive multiple sclerosis (MS). A remarkable decrease of serum neurofilament light chains (sNfL) concentration, a marker of axonal damage, was reported in MS following high-intensity regimen AHSCT, but hints for potential neurotoxicity had emerged. sNfL and brain atrophy were therefore analysed in a cohort of patients with aggressive MS treated with intermediate-intensity AHSCT, exploring whether sNfL might be a reliable marker of disability progression independent from new inflammation (i.e. relapses and/or new/gadolinium-enhancing MRI focal lesions).MethodssNfL concentrations were measured using SIMOA methodology in peripheral blood from relapsing-remitting (RR-) or secondary-progressive (SP-) MS patients undergoing AHSCT (MS AHSCT), collected before transplant and at months 6 and 24 following the procedure. sNfL measured at a single timepoint in SP-MS patients not treated with AHSCT without recent inflammatory activity (SP-MS CTRL) and healthy subjects (HD) were used as controls. The rate of brain volume loss (AR-BVL) was also evaluated by MRI in MS AHSCT cases.ResultsThirty-eight MS AHSCT (28 RR-MS; 10 SP-MS), 22 SP-MS CTRL and 19 HD were included. Baseline median sNfL concentrations were remarkably higher in the MS AHSCT than in the SP-MS CTRL and HD groups (p = 0.005 and <0.0001, respectively), and levels correlated with recent inflammatory activity. After a marginal (not significant) median increase observed at month 6, at month 24 following AHSCT sNfL concentrations decreased compared to baseline by median 42.8 pg/mL (range 2.4-217.3; p = 0.039), reducing by at least 50% in 13 cases, and did not differ from SP-MS CTRL (p = 0.110) but were still higher than in HD (p < 0.0001). Post-AHSCT AR-BVL normalised in 55% of RR-MS and in 30% of SP-MS. The effectiveness and safety of AHSCT were aligned with the literature.ConclusionsNfL concentrations correlated with recent inflammatory activity and were massively and persistently reduced by intermediate-intensity AHSCT. Association with response to treatment assessed by clinical or MRI outcomes was not observed, suggesting a good sensitivity of sNfL for recent inflammatory activity but low sensitivity in detecting ongoing axonal damage independent from new focal inflammation.