Clinically isolated syndrome

Multiple sclerosis (MS) is a heterogeneous disease, and its course is difficult to predict. Prediction models can be established by measuring intrathecally synthesized proteins involved in inflammation, glial activation, and CNS injury.

To determine how these intrathecal proteins relate to the short-term, i.e., 12 months, disease activity in relapsing-remitting MS (RRMS), we measured the intrathecal synthesis of 46 inflammatory mediators and 14 CNS injury or glial activation markers in matched serum and CSF samples from 47 patients with MS (pwMS), i.e., 23 RRMS and 24 clinically isolated syndrome (CIS), undergoing diagnostic lumbar puncture. Subsequently, all pwMS were followed for ≥12 months in a retrospective follow-up study and ultimately classified into "active", i.e., developing clinical and/or radiologic disease activity, n = 18) or "nonactive", i.e., not having disease activity, n = 29. Disease activity in patients with CIS corresponded to conversion to RRMS. Thus, patients with CIS were subclassified as "converters" or "nonconverters" based on their conversion status at the end of a 12-month follow-up. Twenty-seven patients with noninflammatory neurologic diseases were included as negative controls. Data were subjected to differential expression analysis and modeling techniques to define the connectivity arrangement (network) between neuroinflammation and CNS injury relevant to short-term disease activity in RRMS.

Lower age and/or higher CXCL13 levels positively distinguished active/converting vs nonactive/nonconverting patients. Network analysis significantly improved the prediction of short-term disease activity because active/converting patients featured a stronger positive connection between IgG1 and CXCL10. Accordingly, analysis of disease activity-free survival demonstrated that pwMS, both RRMS and CIS, with a lower or negative IgG1-CXCL10 correlation, have a higher probability of activity-free survival than the patients with a significant correlation (p < 0.0001, HR ≥ 2.87).

Findings indicate that a significant IgG1-CXCL10 positive correlation predicts the risk of short-term disease activity in patients with RRMS and CIS. Thus, the present results can be used to develop a predictive model for MS activity and conversion to RRMS.

Histopathologic studies have identified immunoglobulin (Ig) deposition and complement activation as contributors of CNS tissue damage in multiple sclerosis (MS). Intrathecal IgM synthesis is associated with higher MS disease activity and severity, and IgM is the strongest complement-activating immunoglobulin. In this study, we investigated whether complement components (CCs) and complement activation products (CAPs) are increased in persons with MS, especially in those with an intrathecal IgM synthesis, and whether they are associated with disease severity and progression.

CC and CAP levels were quantified in plasma and CSF of 112 patients with clinically isolated syndrome (CIS), 127 patients with MS (90 relapsing-remitting, 14 primary progressive, and 23 secondary progressive), 31 inflammatory neurologic disease, and 44 symptomatic controls from the Basel CSF databank study. Patients with CIS/MS were followed in the Swiss MS cohort study (median 6.3 years). Levels of CC/CAP between diagnosis groups were compared; in CIS/MS, associations of CC/CAP levels with intrathecal Ig synthesis, baseline Expanded Disability Status Scale (EDSS) scores, MS Severity Score (MSSS), and neurofilament light chain (NfL) levels were investigated by linear regression, adjusted for age, sex, and albumin quotient.

CSF (but not plasma) levels of C3a, C4a, Ba, and Bb were increased in patients with CIS/MS, being most pronounced in those with an additional intrathecal IgM production. In CIS, doubling of C3a and C4a in CSF was associated with 0.31 (CI 0.06-0.56; p = 0.016) and 0.32 (0.02-0.62; p = 0.041) increased EDSS scores at lumbar puncture. Similarly, doubling of C3a and Ba in CIS/MS was associated with 0.61 (0.19-1.03; p < 0.01) and 0.74 (0.18-1.31; p = 0.016) increased future MSSS. In CIS/MS, CSF levels of C3a, C4a, Ba, and Bb were associated with increased CSF NfL levels, e.g., doubling of C3a was associated with an increase of 58% (Est. 1.58; CI 1.37-1.81; p < 0.0001).

CNS-compartmentalized activation of the classical and alternative pathways of complement is increased in CIS/MS and associated with the presence of an intrathecal IgM production. Increased complement activation within the CSF correlates with EDSS, future MSSS, and NfL levels, supporting the concept that complement activation contributes to MS pathology and disease progression. Complement inhibition should be explored as therapeutic target to attenuate disease severity and progression in MS.

Racial disparities exist in both neurologic and obstetric populations, underscoring the importance of evaluating pregnancy outcomes in diverse women with multiple sclerosis (MS). The objective of this multicenter retrospective study was to compare pregnancy care and outcomes between Black and Hispanic (underrepresented) and White women with MS.

Demographic and clinical data were extracted from medical records of 9 US MS centers for women with MS/clinically isolated syndrome who delivered live births between 2010 and 2021. Sites identified at last 15 consecutive Black/Hispanic women and a matching number of White women. Socioeconomic factors, pregnancy, and MS care/outcomes were compared between groups (underrepresented and White and then Black and Hispanic) using Wilcoxon rank sum (U statistic and effect size r reported), χ², t tests and logistic regressions as appropriate to data type. Multiple imputation by chained equation was used to account for missing data.

Overall, 294 pregnancies resulting in live births were analyzed ( 81 Black, 67 Hispanic, and 146 White mothers). Relative to underrepresented women, White women lived in areas of higher median (interquartile range [IQR]) Child Opportunity Index (79 [45.8] vs 22 [45.8], U = 3,824, r = 0.56, p < 0.0001) and were more often employed (84.9% vs 75%, odds ratio [OR] 2.57, CI 1.46-4.50, p = 0.0008) and privately insured (93.8% vs 56.8%, OR 11.6, CI 5.5-24.5, p < 0.0001) and more received a 14-week ultrasound (98.6% vs 93.9%, OR 4.66, CI 0.99-21.96, p = 0.027). Mode of delivery was significantly different between the three groups (X²(10,294) = 20.38, p = 0.03); notably, Black women had the highest rates of emergency cesarean deliveries, and Hispanic women highest rates of uncomplicated vaginal deliveries. Babies born to underrepresented women had lower median (IQR) birthweights than babies born to White women (3,198 g [435.3 g] vs 3,275 g [412.5 g], U = 9,255, r = 0.12, p = 0.04) and shorter median (IQR) breastfeeding duration (4.5 [3.3] vs 6.0 [4.2] months, U = 8,184, r = 0.21, p = 0.003). While underrepresented women were younger than White women (mean [SD] 30.9 [4.8] vs 33.8 [4.0], t = 1.97, CI 1.96-3.98, p < 0.0001), their median (Q1-Q3, IQR) Expanded Disability Status Scale was higher (1.5 [1-2.5, 1.5] vs 1 [0-1.5, 1.5], U = 7,260, r = 0.29, p < 0.0001) before pregnancy. Finally, medical records were missing more key data for Black women (19.7% missing vs 8.9% missing, OR 2.54, CI 1.25-5.06, p = 0.008).

In this geographically diverse multicenter cohort, underrepresented women entered pregnancy with higher disability and fewer health care resources. Pregnancy represents a pivotal window where structural factors affect maternal and fetal health and neurologic trajectories; it is a critical period to optimize care and health outcomes.