Rapid rise in the incidence and clinical characteristics of pediatric inflammatory bowel disease in a South-East Asian cohort in Singapore, 1994-2015.

OBJECTIVES: Epidemiological studies on pediatric-onset inflammatory bowel disease (PIBD) are scarce in South-East Asia (SEA). This study aimed to evaluate the incidence trend and clinical characteristics of PIBD in a SEA cohort in Singapore over 22 years (1994-2015).

METHODS: Case records of PIBD ≤18 years from the only two tertiary pediatric hospitals in Singapore were reviewed. The mean annual incidence (MAI) of PIBD was calculated based on Singapore's age-specific population data.

RESULTS: Overall MAI of PIBD was 1.26 per 100 000 (95% confidence interval [CI] 0.56-1.96). During the first decade (1994-2004) MAI was 0.23 per 100 000 (95% CI 0.08-0.39); this rose almost 10-fold to 2.28 per 100 000 (95% CI 1.15-3.41) during the second decade (2005-2015). Linear regression analysis showed significant increase in MAI over the 22-year period (r = 0.826, P < 0001). Of the 228 patients, 61.0% had Crohn's disease (CD), 30.3% ulcerative colitis and 8.7% IBD-unclassified, with a mdian age at diagnosis of 10.47 years and a male predominance (58.3%); 37.7% of them aged <10 years at diagnosis and 17.5% were very early-onset IBD. In CD, 27.3% had stricturing and/or penetrating disease and 21.6% were with perianal disease. Indians had a disproportionately high representation while positive family history was rare (1.3%).

CONCLUSIONS: Although PIBD is uncommon in Singapore, its incidence has risen dramatically over recent decades. A younger age of disease onset and higher proportions of perianal and stricturing/penetrating diseases suggest more aggressive disease than in Western data.