Perspectives in clinical gastroenterology and hepatology
Defining Disease Severity in Inflammatory Bowel Diseases: Current and Future Directions

https://doi.org/10.1016/j.cgh.2015.06.001Get rights and content
Under a Creative Commons license
open access

Although most treatment algorithms in inflammatory bowel disease (IBD) begin with classifying patients according to disease severity, no formal validated or consensus definitions of mild, moderate, or severe IBD currently exist. There are 3 main domains relevant to the evaluation of disease severity in IBD: impact of the disease on the patient, disease burden, and disease course. These measures are not mutually exclusive and the correlations and interactions between them are not necessarily proportionate. A comprehensive literature search was performed regarding current definitions of disease severity in both Crohn’s disease and ulcerative colitis, and the ability to categorize disease severity in a particular patient. Although numerous assessment tools for symptoms, quality of life, patient-reported outcomes, fatigue, endoscopy, cross-sectional imaging, and histology (in ulcerative colitis) were identified, few have validated thresholds for categorizing disease activity or severity. Moving forward, we propose a preliminary set of criteria that could be used to classify IBD disease severity. These are grouped by the 3 domains of disease severity: impact of the disease on the patient (clinical symptoms, quality of life, fatigue, and disability); measurable inflammatory burden (C-reactive protein, mucosal lesions, upper gastrointestinal involvement, and disease extent), and disease course (including structural damage, history/extension of intestinal resection, perianal disease, number of flares, and extraintestinal manifestations). We further suggest that a disease severity classification should be developed and validated by an international group to develop a pragmatic means of identifying patients with severe disease. This is increasingly important to guide current therapeutic strategies for IBD and to develop treatment algorithms for clinical practice.

Keywords

Disease Severity
Disease Course
Inflammatory Bowel Disease

Abbreviations used in this paper

CD
Crohn’s disease
CDAI
Crohn’s Disease Activity Index
CRP
C-reactive protein
ECCO
European Crohn’s and Colitis Organisation
EIM
extraintestinal manifestation
ESR
erythrocyte sedimentation rate
HBI
Harvey–Bradshaw Index
IBD
inflammatory bowel disease
PRO
patient-reported outcome
QoL
quality of life
UC
ulcerative colitis

Cited by (0)

Conflicts of interest The authors disclose the following: Laurent Peyrin-Biroulet has received consulting and/or lecture fees from AbbVie, Boehringer Ingelheim, Bristol-Myers Squibb, Ferring, Genentech, Hospira, Janssen, Merck, Mitsubishi, Norgine, Pharmacosmos, Pilège, Shire Pharmaceuticals, Takeda, Therakos, Tillotts Pharma, UCB Pharma, and Vifor Pharma; Julián Panés has received speaker fees from, acted as a scientific consultant for, and/or received research grants from AbbVie, Boehringer Ingelheim, Bristol-Myers Squibb, Ferring, Genentech, Janssen, MSD, NovoNordisk, Nutrition Science Partners, Pfizer, Shire Pharmaceuticals, Takeda, and Tigenics; William Sandborn has received consulting fees, lecture fees, and/or research support from AbbVie, ActoGeniX, AGI Therapeutics, Alba Therapeutics Albireo, Alfa Wasserman, Amgen, AM-Pharma BV, Anaphore, Aptalis, Astellas, Athersys, Atlantic Healthcare, BioBalance, Boehringer-Ingelheim, Bristol-Myers Squibb, Celgene, Celek, Cellerix, Cerimon, ChemoCentryx, CoMentis, Cosmo Technologies, Coronado Biosciences, Cytokine Pharmasciences, Eagle, Eisai Medical Research, Elan, EnGene, Eli Lilly, Enteromedics, Exagen Diagnostics, Ferring, Flexion Therapeutics, Funxional Therapeutics, Genentech, Genzyme, Gilead, Given Imaging, GlaxoSmithKline, Human Genome Sciences, Ironwood, Janssen, KaloBios, Lexicon, Lycera, Meda, Merck & Co, Merck Research Laboratories, MerckSerono, Millennium, Nisshin Kyorin, Novo Nordisk, NPS Pharmaceuticals, Optimer, Orexigen, PDL Biopharma, Pfizer, Procter and Gamble, Prometheus Laboratories, ProtAb, Purgenesis Technologies, Receptos, Relypsa, Salient, Salix, Santarus, Shire Pharmaceuticals, Sigmoid Pharma, Sirtris (a GSK company), S.L.A. Pharma (UK), Targacept, Teva, Therakos, Tillotts, TxCell SA, UCB Pharma, Vascular Biogenics, Viamet, and Warner Chilcott UK; Séverine Vermeire has received consulting fees and/or grant/research support from, and/or been a speaker for AbbVie, Centocor, Ferring, Genentech/Roche, MSD, Novartis, Pfizer, Shire Pharmaceuticals, Takeda, and UCB Pharma; Silvio Danese has served as a speaker, consultant, and/or advisory board member for AbbVie, Actelion, Alphawasserman, Astra Zeneca, Cellerix, Cosmo Pharmaceuticals, Ferring, Genentech, Grunenthal, Johnson&Johnson, Millennium, Merck & Co, NovoNordisk, Nycomed, Pfizer, Pharmacosmos, Schering-Plough, Salix, Takeda, UCB Pharma, and Vifor; Brian Feagan has received consulting fees, lecture fees, and/or research support from AbbVie, ActogeniX, Albireo Pharma, Amgen, Astra Zeneca, Avaxia Biologics, Inc, Avir Pharma, Axcan, Baxter Healthcare Corp, Boehringer Ingelheim, Bristol-Myers Squibb, Calypso Biotech, Celgene, Centocor, Elan/Biogen, EnGene, Ferring Pharmaceuticals, Genentech, GiCare Pharma, Gilead, Given Imaging, GlaxoSmithKline, Ironwood Pharma, Johnson & Johnson/Janssen, Kyowa Kakko, Kirin Co Ltd, Lexicon, Lilly, Merck, Millennium, Nektar, Novartis, Novo Nordisk, Pfizer, Prometheus Therapeutics and Diagnostics, Prometheus Laboratories, Receptos, Salix Pharmaceuticals, Santarus, Sanofi, Serono, Shire Pharmaceuticals, Sigmoid Pharma, Synergy Pharma, Inc, Takeda, Teva, TiGenix, Tillotts Pharma AG, UCB Pharma, Vertex Pharma, VHsquared Ltd, Warner-Chilcott, Wyeth, Zealand Pharma, and Zyngenia, and is a member of the Board of Directors of Roberts Clinical Trials, Inc; Jean-Frédéric Colombel has acted as a consultant, advisory board member, and/or speaker for AbbVie, Bristol-Myers Squibb, Ferring, Genentech, Giuliani SPA, Given Imaging, Merck & Co, Millennium, Pfizer, Prometheus Laboratories, Sanofi, Schering Plough, Takeda, Teva, and UCB Pharma; Stephen Hanauer has acted as a consultant or advisory board member for and/or received grant/research support from AbbVie, Bristol-Myers Squibb, Caremark, Centocor, Elan, McNeal Pharma, Millennium, Novartis, Procter and Gamble, and Salix; and Beth Rycroft is an employee of AbbVie, Inc, and may own AbbVie stock and/or options.

Funding AbbVie, Inc, funded the literature analysis, provided writing support, and reviewed and approved the publication. Juliette Allport of Leading Edge (part of the Lucid Group) (Burleighfield House, Buckinghamshire, UK) provided medical writing and editorial support to the authors in the development of this manuscript. Financial support to Leading Edge for medical writing and editorial assistance was provided by AbbVie.