Phenotypic Variation in Paediatric Inflammatory Bowel Disease by Age: A Multicentre Prospective Inception Cohort Study of the Canadian Children IBD Network

J Dhaliwal; T D Walters; D R Mack; H Q Huynh; K Jacobson; A R Otley; J Debruyn; W El-Matary; C Deslandres; M E Sherlock; J N Critch; K Bax; E Seidman; P Jantchou; A Ricciuto; M Rashid; A M Muise; E Wine; M Carroll; S Lawrence; J Van Limbergen; E I Benchimol; P Church; A M Griffiths

doi:10.1093/ecco-jcc/jjz106

Phenotypic Variation in Paediatric Inflammatory Bowel Disease by Age: A Multicentre Prospective Inception Cohort Study of the Canadian Children IBD Network

J Crohns Colitis. 2020 May 21;14(4):445-454. doi: 10.1093/ecco-jcc/jjz106.

Authors

J Dhaliwal¹, T D Walters¹, D R Mack², H Q Huynh³, K Jacobson⁴, A R Otley⁵, J Debruyn⁶, W El-Matary⁷, C Deslandres⁸, M E Sherlock⁹, J N Critch¹⁰, K Bax¹¹, E Seidman¹², P Jantchou⁸, A Ricciuto¹, M Rashid⁵, A M Muise¹, E Wine³, M Carroll³, S Lawrence⁴, J Van Limbergen⁵, E I Benchimol¹², P Church¹, A M Griffiths¹

Affiliations

¹ SickKids Hospital, University of Toronto, Toronto, ON, Canada.
² Children's Hospital of Eastern Ontario, University of Ottawa, Ottawa, ON, Canada.
³ Stollery Children's Hospital, University of Alberta, Edmonton, AB, Canada.
⁴ B.C. Children's Hospital, University of British Columbia, Vancouver, BC, Canada.
⁵ IWK Health Centre, Dalhousie University, Halifax, NS, Canada.
⁶ Alberta Children's Hospital, University of Calgary, Calgary, AB, Canada.
⁷ Max Rady College of Medicine, University of Manitoba, Winnipeg, MB, Canada.
⁸ CHU Sainte-Justine, Universite de Montreal, Montreal, QC, Canada.
⁹ McMaster Children's Hospital, McMaster University, Hamilton, ON, Canada.
¹⁰ Janeway Children's Health and Rehabilitation Centre, Memorial University, St John's, NL, Canada.
¹¹ Children's Hospital of Western Ontario, University of Western Ontario, London, ON, Canada.
¹² Montreal Children's Hospital, McGill University Faculty of Medicine, Montreal, QC, Canada.

Abstract

Background and aims: Incidence of paediatric inflammatory bowel disease [IBD] in Canada is among the highest worldwide, and age of onset may be decreasing. In a multicentre nationwide inception cohort study, we examined variation in phenotype of IBD throughout the paediatric age spectrum.

Methods: Children aged ≥2 years [y] and <17y [A1 age at diagnosis], with new onset IBD, were systematically evaluated at sites of the Canadian Children IBD Network. Prospectively recorded phenotypic data were compared between age groups.

Results: Among 1092 children (70% Caucasian; 64% Crohn's disease [CD], 36% ulcerative colitis/inflammatory bowel disease unclassified [UC/IBD-U]; median age 13 y, interquartile range [IQR] 11-15 y), 210 [19%] were diagnosed before the age of age 10 y [Paris A1a] and 43 [4%] before age 6 y (very-early-onset [VEO-IBD]). CD was less common in younger children [42%, 56%, 66%, respectively, of VEO-IBD, A1a; A1b]. Colon-only IBD [UC/IBDU or CD-colon] was present in 81% of VEO-IBD and 65% of A1a; ileal disease increased progressively, reaching plateau at age 10 y. CD location was ileocolonic [L3] in 53% overall. Ileitis [L1] increased with age [6% of VEO-IBD; 13% of A1a; 21% of A1b], as did stricturing/penetrating CD [4% of A1a; 11% of A1b]. At all ages UC was extensive [E3/E4] in >85%, and disease activity moderate to severe according to Physician's Global Assessment [PGA] and weighted Paediatric Crohn's Disease Activity Index/Paediatric Ulcerative Colitis Activity Index [wPCDAI/PUCAI] in >70%. Heights were modestly reduced in CD [mean height z score -0.30 ± 1.23], but normal in UC/IBD-U.

Conclusions: Paris classification of age at diagnosis is supported by age-related increases in ileal disease until age 10 years. Other phenotypic features, including severity, are similar across all ages. Linear growth is less impaired in CD than in historical cohorts, reflecting earlier diagnosis.

Keywords: IBD; paediatrics; phenotype.

Publication types

Multicenter Study

MeSH terms

Age of Onset
Biological Variation, Population
Canada / epidemiology
Child
Cohort Studies
Colitis, Ulcerative* / diagnosis
Colitis, Ulcerative* / epidemiology
Colitis, Ulcerative* / physiopathology
Crohn Disease* / diagnosis
Crohn Disease* / epidemiology
Crohn Disease* / physiopathology
Disease Progression
Female
Humans
Incidence
Male
Prospective Studies
Severity of Illness Index

Supplementary concepts

Pediatric Crohn's disease
Pediatric ulcerative colitis