Inflamm Bowel Dis. 2021 Jun 28;izab124. doi: 10.1093/ibd/izab124. Online ahead of print.

Rocio Sedano ^1 2, Tran M Nguyen ², Ahmed Almradi ^1 2, Florian Rieder ^3 4, Claire E Parker ², Lisa M Shackelton ², Geert D'Haens ^2 5, William J Sandborn ^2 6, Brian G Feagan ^1 2 7, Christopher Ma ^2 8, Vipul Jairath ^1 2 7

Author information

• ¹Division of Gastroenterology, Department of Medicine, Western University, London, Ontario, Canada.
• ²Alimentiv Inc., London, Ontario, Canada.
• ³Department of Inflammation and Immunity, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, Ohio, USA.
• ⁴Department of Gastroenterology, Hepatology and Nutrition, Digestive Diseases and Surgery Institute, Cleveland Clinic Foundation, Cleveland, Ohio, USA.
• ⁵Department of Gastroenterology, Amsterdam University Medical Centers, Amsterdam, the Netherlands.
• ⁶Division of Gastroenterology, University of California, San Diego, La Jolla, California, USA.
• ⁷Department of Epidemiology and Biostatistics, Western University, London, Ontario, Canada.
• ⁸Division of Gastroenterology and Hepatology, Cumming School of Medicine, Departments of Medicine & Community Health Sciences, University of Calgary, Calgary, Alberta, Canada.

Abstract

Background: Several indices exist to measure pouchitis disease activity; however, none are fully validated. As an initial step toward creating a validated instrument, we identified pouchitis disease activity indices, examined their operating properties, and assessed their value as outcome measures in clinical trials.

Methods: Electronic databases were searched to identify randomized controlled trials including indices that evaluated clinical, endoscopic, or histologic pouchitis disease activity. A second search identified studies that assessed the operating properties of pouchitis indices.

Results: Eighteen randomized controlled trials utilizing 4 composite pouchitis disease activity indices were identified. The Pouchitis Disease Activity Index (PDAI) was most commonly used (12 of 18; 66.7%) to define both trial eligibility (8 of 12; 66.7%), and outcome measures (12 of 12; 100%). In a separate search, 21 studies evaluated the operating properties of 3 pouchitis indices; 90.5% (19 of 21) evaluated validity, of which 42.1% (8 of 19) evaluated the construct validity of the PDAI. Criterion validity (73.7%; 14 of 19) was evaluated through correlation of the PDAI with fecal calprotectin (FCP; r = 0.188 to 0.71), fecal lactoferrin (r = 0.570 to 0.582), and C-reactive protein (CRP; r = 0.584). Two studies assessed correlation of the modified PDAI (mPDAI) with FCP (r = 0.476 and r = 0.565, respectively). Fair to moderate inter-rater reliability of the PDAI (k = 0.440) and mPDAI (k = 0.389) was reported in a single study. Responsiveness of the PDAI pre-antibiotic and postantibiotic treatment was partially evaluated in a single study of 12 patients.

Conclusions: Development and validation of a specific pouchitis disease activity index is needed given that existing instruments are not valid, reliable, or responsive.