Incidence of ulcerative colitis and Crohn's disease in Danish children: Still rising or levelling out?

Abstract

Aim To describe the development in incidence and prevalence of paediatric inflammatory bowel disease (IBD) in Eastern Denmark during a six-year period. Methods All patients < 15 years with IBD in Eastern Denmark in the two following periods were included: 1) 1.1.1998–31.12.2000 and 2) 1.1.2002–31.12.2004. The mean background population (children < 15 years) in Eastern Denmark was 421,898 persons in period 1 and 439,443 persons in period 2. Patients were identified using the ICD-10 classification (DK500-519). The following data were extracted from the files: diagnosis, change in diagnosis, age at diagnosis, localisation, extra-intestinal symptoms, surgery and county of residence. Incidence and prevalence for ulcerative colitis (UC), Crohn's disease (CD) and indeterminate colitis (IC) were calculated per 100,000 children < 15 years. Results 98 patients (50 UC, 44 CD, 4 IC), median age 9.8 years (range 2–14) and 12.8 (range 0.5–14) for UC and CD, respectively, were identified in period 1. In the second period 145 patients (70 UC, 64 CD, 11 IC) were included with a median age of 11 years (range 1–14) and 12.5 (range 0.5–14) for UC and CD, respectively. The prevalence of IBD was 15.8 and 20.3 in 1998–2000 and 2002–2004, respectively. The incidence of IBD was 4.3 (UC: 1.8; CD: 2.3; IC: 0.2) and 6.1 (UC: 2.6; CD: 3.1; IC: 0.3), respectively, for the two periods ( p > 0.05). Conclusions In our study we found an insignificant increase in the incidence of both CD and UC, indicating that the previously reported rising incidence might be levelling out.