Validation of the novel Eosinophilic Esophagitis Impact Questionnaire

Abstract

Background: Eosinophilic esophagitis (EoE) has a detrimental effect on health-related quality of life (HRQOL). The Eosinophilic Esophagitis Impact Questionnaire (EoE-IQ) is a novel patient-reported outcome (PRO) measure assessing the impact of EoE on HRQOL. To assess suitability of the EoE-IQ, its measurement properties were evaluated.

Methods: Using baseline and week 24 data from the pivotal, randomized, placebo-controlled, multinational phase 3 R668-EE-1774 trial (NCT03633617) of dupilumab, we evaluated EoE-IQ's measurement properties (including reliability, construct and known-groups validity, and ability to detect change) and established the threshold for change in scores that can be considered clinically meaningful.

Results: The analysis population comprised 239 adults and adolescents with EoE. Mean age was 28.1 (standard deviation, 13.14) years; 63.6% were male, and 90.4% were White. Reliability estimates for the EoE-IQ average score exceeded acceptable thresholds for patients who were stable as indicated by ratings of Patient Global Impression of Severity (PGIS) and Change (PGIC) (intraclass correlation coefficients, 0.75 and 0.81). Construct validity correlations with other EoE-specific PRO scores were moderate at baseline (|r|= 0.44-0.60) and moderate to strong at week 24 (|r|= 0.61-0.72). In known-groups analysis, EoE-IQ average score discriminated among groups of patients at varying EoE severity levels defined by PGIS scores. A ≥ 0.6-point reduction in EoE-IQ average score (where scores range from 1 to 5, with higher scores indicating worse HRQOL) from baseline to week 24 can be considered clinically meaningful.

Conclusions: The EoE-IQ's measurement properties are acceptable, making it a valid, reliable measure of the HRQOL impacts of EoE among adults and adolescents.

Trial registration: ClinicalTrials.gov, NCT03633617. Registered August 14, 2018, https://ichgcp.net/clinical-trials-registry/NCT03633617 .

Conflict of interest statement

STT is an employee of Sanofi Global and may hold stocks and/or shares in the company. EM, SK, and XS are employees of Regeneron Pharmaceuticals and may hold shares and/or stock options in the company. AY is an employee of Adelphi Values who developed the EoE-IQ as part of research funded by Regeneron Pharmaceuticals, and JS was an employee of Adelphi Values at the time the research was conducted. TS is an employee of Clinical Outcomes Solutions, who conducted research used to further develop the EoE-IQ, as part of research funded by Regeneron Pharmaceuticals. MC has received consultant fees from Regeneron, Allakos, Adare/Ellodi, Shire/Takeda, AstraZeneca, Sanofi, Bristol Myers Squibb, Phathom, Nexstone Immunology, and Recludix Pharma and has received research funding from Regeneron, Allakos, Shire/Takeda, AstraZeneca, Adare/Ellodi, Bristol Myers Squibb, and Danone . JMS has grant support and consultant fees from Regeneron and Sanofi.

© 2023. The Author(s).