TOPLINE

Patients who were younger and had multifocal clinical presentation at their first clinically isolated syndrome (CIS) had increased odds of a multiple sclerosis (MS) diagnosis later. Certain MRI findings were also linked to elevated odds of MS diagnosis.

METHODOLOGY

• Researchers conducted a systematic review and meta-analysis to identify factors at first demyelinating event (CIS) that predicted the odds of a later diagnosis of MS.
• They searched multiple databases through December 2025 and included 72 studies involving 9915 adults with CIS across multiple countries. Most studies (81.9%) were prospective cohorts.
• Multiple factors including demographics, clinical presentation, MRI variables, and cerebrospinal fluid biomarkers were evaluated.
• The primary outcome was a diagnosis of MS after a CIS event. The median follow-up duration was 37.5 months. 

TAKEAWAY

• Younger age at CIS onset was associated with 1.6-fold increased odds of MS diagnosis (34 studies; P = .0001), with high heterogeneity (I² = 76.4%).
• Multifocal presentation at CIS onset was associated with 1.55-fold increased odds of MS diagnosis (6 studies; P = .022), with no heterogeneity (I² = 0%).
• A higher number of T2 lesions on MRI was associated with 7.46-fold increased odds of MS diagnosis (10 studies; P = .019; I² = 93.1%). Other MRI features linked to elevated odds of MS included periventricular, corpus callosum, infratentorial, spinal cord, and gadolinium-enhancing lesions (P < .05 for all), with I² ranging from 0% to 61.8% across respective studies.
• Cerebrospinal fluid oligoclonal bands (38 studies; I² = 65.2%) and pleocytosis (6 studies; I² = 75.6%) were also linked to increased odds of a later MS diagnosis (P < .05 for both).

IN PRACTICE

"[The findings are] highly relevant in the context of the current era of MS management, which focuses on early and effective treatment to prevent further disease activity and neurological disability," the authors of the study wrote.

SOURCE

The study was led by María Paula Zafra-Sierra, Fundación Santa Fe de Bogotá in Bogotá, Colombia, and Carolina Ferreira-Atuesta, University Hospital Zurich in Zurich, Switzerland. It was published online on July 31 in European Journal of Neurology.

LIMITATIONS

The analyses had substantial heterogeneity. Changes in diagnostic criteria, especially the 2017 McDonald criteria, influenced diagnosis rates and comparability. Regional disparities in access to healthcare may have affected the time to diagnosis and confirmation of MS.

DISCLOSURES

No funding or conflicts of interest were reported by the authors.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.