Prevalence of Inflammatory Bowel Disease in Pediatric and Adult Populations: Recent Estimates From Large National Databases in the United States, 2007-2016.

BACKGROUND: The latest estimate of the prevalence of inflammatory bowel disease (IBD) in the United States was based on 2009 data, which indicates a need for an up-to-date re-estimation. The objectives of this study were to investigate the prevalence of all forms of IBD including ulcerative colitis (UC), Crohn's disease (CD), and IBD unspecified (IBDU).

METHODS: Pediatric (age 2-17) and adult (age ≥18) IBD patients were identified from 2 large claims databases. For each year between 2007 and 2016, prevalence was calculated per 100,000 population and standardized based on the 2016 national Census. A fixed-effects meta-analytical model was used for overall prevalence.

RESULTS: The pediatric prevalence of IBD overall increased by 133%, from 33.0/100,000 in 2007 to 77.0/100,000 in 2016. Among children, CD was twice as prevalent as UC (45.9 vs 21.6). Prevalence was higher in boys than girls for all forms of IBD, in contrast to the adult population where the prevalence was higher in women than men. We also found that the 10-17 age subgroup was the major contributor to the rising pediatric IBD prevalence. For adults, the prevalence of IBD overall increased by 123%, from 214.9 in 2007 to 478.4 in 2016. The prevalence rates of UC and CD were similar (181.1 vs 197.7) in 2016.

CONCLUSIONS: Inflammatory bowel disease continues to affect a substantial proportion of the US population. In 2016, 1 in 209 adults and 1 in 1299 children aged 2-17 were affected by IBD. Prevalence of IBD has been increasing compared with previously published 2009 data.