Real-World Multinational Survey of Chronic Inflammatory Demyelinating Polyneuropathy: Disease Characteristics and Therapeutic Landscape

Background and Aims: Chronic inflammatory demyelinating polyneuropathy (CIDP) is an immune-mediated syndrome characterized by progressive muscle weakness and sensory impairment. Clinical similarities with other neuropathies can cause misdiagnoses and delayed diagnoses. Additionally, a large proportion of patients appropriately treated according to current guidelines still show residual disability. This real-world study aimed to characterize a global cohort of patients with CIDP. Methods: Data were drawn from the Adelphi CIDP Disease Specific Programme, a cross-sectional survey with retrospective data collection, conducted in China, France, Germany, Italy, Japan, Spain, the United Kingdom, and the United States between September 2022 and April 2023. Neurologists and neuromuscular specialists reported on patient demographic and clinical characteristics at the time of the survey. Patients self-reported treatment satisfaction, disease control, and health-related outcome measures. Results: Overall, 164 physicians provided data for 1056 patients, with 428 (40.5%) providing self-reported data. Patients were diagnosed with typical CIDP (69.2%) and variant CIDP (30.8%). Overall, initial misdiagnosis occurred in 37.2% of patients, with a median (interquartile range) diagnostic delay of 6.0 (3.0–12.0) months. Maintenance therapy was prescribed for 81.6% of patients, with corticosteroid use ranging from 25.7% in the United States to 80.0% in China. Some patients were dissatisfied by treatment outcomes (11.0%) and symptom control (12.2%). Overall, mean (SD) patient-reported scores were 62.1 (20.4) for I-RODS, 35.0 (11.1) for FACIT fatigue, and 0.662 (0.253) for EQ-5D-5L. Interpretation: Diagnostic delay and misdiagnoses were common occurrences across typical CIDP and variant CIDP. Despite the use of guideline treatments, there were unmet needs and a continued disease burden for patients.