Incidence, prevalence and clinical presentation of inflammatory bowel diseases in Northern France: a 30-year population-based study

Background

In industrialized countries, the incidence of inflammatory bowel disease (IBD) appears stabilized. This study examined the incidence and phenotype of IBD in Northern France over a 30-year period.

Methods

Including all IBD patients recorded in the EPIMAD population-based registry from 1988 to 2017 in Northern France, we described the incidence and clinical presentation of IBD according to age, sex and time.

Findings

A total of 22,879 incident IBD cases were documented (59% (n = 13,445) of Crohn’s disease (CD), 38% (n = 8803) of ulcerative colitis (UC), 3% (n = 631) of IBD unclassified (IBDU)). Over the study period, incidence of IBD, CD and UC was 12.7, 7.2 and 5.1 per 10⁵ person-years, respectively. The incidence of CD increased from 5.1/10⁵ in 1988–1990 to 7.9/10⁵ in 2015–2017 (annual percent change (APC): +1.9%, p < 0.0001). The incidence of UC increased from 4.5/10⁵ to 6.1/10⁵ (APC: +1.3%, p < 0.0001). The largest increase was observed in children (+4.3% in CD, p < 0.0001; +5.4% in UC, p < 0.0001) followed by young adults aged 17–39 years (+1.9% in CD, p < 0.0001; +1.5% in UC, p < 0.0001). The increase in UC incidence was significantly higher in women than in men (+1.9% in women, +0.8% in men; p = 0.006). We estimated that in our area, by 2030, nearly 0.6% of the population will have IBD.

Interpretation

The persistent increase of IBD incidence among children and young adults but also in women with UC in Northern France, suggests the persistence of substantial predisposing environmental factors.

Funding

Santé Publique France; INSERM; Amiens, Lille and Rouen University Hospitals.