Incidence, Prevalence, and Treatment Patterns in Chronic Inflammatory Demyelinating Polyneuropathy: Data Analysis of US Claims.

INTRODUCTION

Chronic inflammatory demyelinating polyneuropathy (CIDP) is an autoimmune-mediated neuropathy typically presenting as symmetrical motor weakness and/or sensory impairment. As the most recent data describing the epidemiology of CIDP in the USA are approximately 25 years old, this work aimed to provide updated estimates on the incidence and prevalence of CIDP in the USA and information on patient characteristics and treatment patterns.

METHODS

This retrospective claims-based cohort study utilized Inovalon closed claims data from 2016 through 2023. Identified patients with CIDP were those with ≥2 claims containing ICD-10 codes for CIDP (G61.81) separated by ≥30 days. The incident cohort was defined as patients with CIDP and continuous enrollment for all of 2022 and 2023, with no diagnosis of CIDP prior to 2023. The prevalent cohort was defined as patients with CIDP and continuous enrollment in 2023. Incidence and prevalence rates were determined for the study population, then adjusted for age and sex and extrapolated to the total US population.

RESULTS

The incident and prevalent cohorts included 913 and 8,697 patients, respectively. The median ages for males and females, respectively, were 59 and 53 years in the incident cohort and 60 and 56 years in the prevalent cohort. The most common comorbidity was diabetes mellitus. Among patients who received treatment in 2023, a majority in both cohorts received steroids, followed by immunoglobulin. Patients in both cohorts were most frequently seen by neurology specialists, and these specialists were the most frequent prescribers of immunoglobulin. Adjusted incidence and prevalence rates for CIDP in 2023 were 2.8 (95% confidence interval [CI] 2.7-2.9) and 23.3 (95% CI 23.1-23.5), respectively, per 100,000 persons, yielding an estimate of 77,058 total individuals with CIDP currently living in the USA. Incidence and prevalence rates in patients aged ≥55 years were generally higher in males compared with females.

CONCLUSION

This study reports increased epidemiologic rates for CIDP and provides insights into patient characteristics and current treatment patterns. These updated estimates can inform strategic healthcare resource planning, although they may be limited by the potential misclassification of CIDP diagnoses in the claims data.