The International GBS Outcome Study (IGOS)

Introduction:

The International GBS Outcome Study (IGOS) aims to define the determinants and predictors of the clinical course of the Guillain-Barré syndrome (GBS) and to facilitate the conduct of therapeutic studies.  

Methods:

IGOS is a observational prospective cohort study conducted in 21 countries across 5 continents. All patients within the diagnostic spectrum of GBS are included irrespective of age, variant forms, disease severity and treatment. Patients are included within two weeks from onset of weakness. Data is collected at predefined standard time points during a follow-up period of 1 to 3 years. Data collected focus on preceding events, demographic factors, clinical symptoms and signs and severity. In addition, nerve conduction studies and biomaterials are collected for future biomarker studies.

Results:

In May 2024 we have reached the aimed number of 2000 patients included in IGOS with a follow-up period of 3 year. Therefore it is not possible to include new patients in IGOS.  The majority of patients (n=1110, 60%) were male and the median age was 52 (IQR: 34-65, total number of children n=155, 8.4%). The sensorimotor variant was the most frequently reported variant (n=1046, 60%). IVIg was provided to 1319 patients (72%), while 203 (13%) received plasma exchange. At six months, 82% of patients (n=1172) were able to walk. To date, the IGOS consortium has published 18 studies and at present 28 studies are ongoing, ranging from studies on preceding events, genetic studies, proteomics, diagnostic criteria, electrophysiology, prognostic studies, validation of (patient-reported) outcome measures and new trial designing. Two treatment studies are currently ongoing in IGOS. The IGOS consortium and external researchers are invited to submit proposals for additional studies.

Conclusions:

The IGOS has resulted in the largest international real-world data and biobank available for research in GBS. Multiple studies are ongoing and we hope to facilitate additional research in the future.

Funding agency: GBS-CIDP Foundation