Systematic Review: Disease Activity Indices in Eosinophilic Esophagitis

Objectives There is no clear consensus regarding the most appropriate measure(s) of eosinophilic esophagitis (EoE) disease activity. We aimed to identify all scoring indices used for the measurement of disease activity in EoE, appraise their operating properties, and discuss their value as outcome measures. Methods MEDLINE, EMBASE, and CENTRAL (The Cochrane library) were searched from inception to 11 May 2016. Randomized controlled trials (RCTs), cohort, case-control, and cross-sectional studies that reported outcomes to measure EoE disease activity or response to treatment were eligible. Operating properties of histologic, endoscopic, and patient reported/symptomatic and health-related quality of life measures were critically appraised according to guidelines proposed by the United States Food and Drug Administration. Results Of 4,373 citations, 130 studies were eligible, of which 20 were RCTs. Although no index met all evaluative criteria, we found that: (1) the EoE histologic scoring system (EoEHSS) is the most valid histologic measure; (2) the Endoscopic Reference Score (EREFS) is the most reliable and responsive endoscopy measure; and (3) the Eosinophilic Esophagitis Activity Index (EEsAI) or the Dysphagia Symptoms Questionnaire (DSQ) had superior construct validity and responsiveness in adults. The Pediatric Quality of Life Inventory EoE was the most valid pediatric symptomatic measure. Conclusions Current evidence supports the use of the EoEHSS and EREFS as measures of histologic and endoscopic EoE disease activity, respectively, and the EEsAI, DSQ, or Pediatric Quality of Life Inventory EoE as measures of adult and pediatric symptoms. Additional research is needed to optimize endpoint configuration to facilitate development of new therapies.