Aim An accurate understanding of trends in incidence and prevalence as well as disease burden of paediatric-onset inflammatory bowel disease (PIBD) within a large region are essential to plan services and unravel possible aetiological factors. We aimed to delineate these trends together with numbers of PIBD cases requiring surgery and immunomodultory/biological therapies.
Methods Incident and prevalent cases of PIBD in South-East Scotland were prospectively collected from service establishment in August 1997 to April 2011. All cases of Crohn's disease (CD), ulcerative colitis (UC) and IBD-unclassified (IBDU) were diagnosed by standard criteria and detailed demographic information and both medical and surgical therapies were recorded on a departmental database. Date of first attendance and of discharge from paediatric services was also recorded, allowing calculation of incidence and yearly point prevalence (1st April). To allow for accrual of cases during the establishment phase of the PIBD service, only data from 2000-2010 was used for incident and prevalent rates. Rates were sex-adjusted and statistical analysis carried out using GraphPad Prism and R.
Results A total of 318 children with IBD were cared for during the 14 year period. The cohort comprised of 206 CD (65%), 73 UC (23%) and 39 IBDU (12%) cases. The median age at diagnosis was 11.6 years (IQR 9.1-13.4 years) with an overall preponderance of males. Overall incidence of IBD in the period 2000-2010 was 6.4/100,000/year with a significant rise from 5.6/100,000/year to 7.2/100,000/year between the periods of 2000-2004 and 2005-2010 (p=0.002). This was mainly driven by an increase in the incidence of CD in males from the earlier (4.0/100,000/year) to the later (5.5/100,000/year) epoch (p=0.002). The overall rates of UC (1.5/100,000/year) and IBDU (0.9/100,000/year) remained relatively stable. The point prevalence of IBD rose from 23.1/100,000 (2000-2004) to 48.7/100,000 (2005-2010). During the total follow up time of 1432 patient years, 68% of patients required azathioprine, 27% methotrexate, 18% biologicals and 21% needed IBD-related surgery.
Conclusion Evaluating a well defined paediatric population over a 14 year period gives a clear indication of the rising trend in the incidence and prevalence of PIBD. In addition, knowledge of the requirement for medical and surgical therapies allows for the tailoring of local service provision.