Trends in Hospitalization Rates and Disease Behavior in Pediatric Inflammatory Bowel Disease in the United States from 2000 to 2009

Abstract

Recent studies suggest an increasing incidence of inflammatory bowel disease (IBD) in children. However, the impact of this increase on the secular trends of inpatient care and disease burden in hospitalized children with IBD is unknown. Therefore, the aims of this study were to evaluate the rate of hospitalization and disease behavior in hospitalized children with IBD in the United States from 2000 to 2009. We used the U.S. Healthcare Cost and Utilization Project Kids' Inpatient Database. Data were weighted to generate national-level estimates. We identified 61,779 cases of pediatric IBD during four triennial periods from 2000 to 2009. During the period of study, the rate of hospitalization of children with any diagnosis of IBD increased from 43.6 to 72.0 (cases per 10,000 total hospitalizations entered into the database per year; 2000 vs. 2009; P < 0.001). Specifically, for Crohn's disease (CD) the rate increased from 28.3 to 45.7 (P < 0.001) and for ulcerative colitis (UC) 15.2 to 26.1 (P < 0.001). There was an increasing trend in the rate of hospitalization in pediatric cases of IBD overall, and CD and UC individually (evaluation of entire time period, Cochran-Armitage test for trend, P < 0.001 for each disease). The age distribution of hospitalized children with IBD did not change over the decade of study. Mortality (1 per 1,000 cases of IBD) and length of hospital stay (LOS; median, 4 days) remained constant. Hospitalization charges (adjusted for inflation) increased (median, $11,614 to $20,724, P < 0.001). Significant increasing trends were found for comorbid disease burden and systemic complications (including electrolyte disturbances and anemia), and the need for blood transfusion and parenteral nutrition (P < 0.001 for each). There, also, was an increase in the number of cases with fistulae, obstruction, and perianal disease (P <0.001 for each). In comparison of IBD and non-IBD cases, those with IBD had lower mortality, longer LOS, and higher charges (P < 0.001 for each). Case-control matching demonstrated a lower risk of death (adjusted odds ratio, aOR 0.25, 95% CI, 0.20-0.31), longer LOS (aOR 2.48, 95% CI, 2.40-2.50), and higher charges (aOR 1.92, 95% CI, 1.88-1.96) in those with IBD. These results demonstrate an increasing trend in the number of pediatric cases with IBD admitted to the hospital from 2000 to 2009. Moreover, we found an increasing trend in disease-specific and systemic complications in these children along with an increasing cost of the hospital stay. These findings are consistent with earlier studies demonstrating that the epidemiology of pediatric IBD is changing as demonstrated by an increase in hospitalized cases. Also, these data suggest there has been an increase in the severity and frequency of complicated disease.