Geographical heterogeneity in the disease characteristics and management of patients with inflammatory bowel disease, the preliminary results of a Chinese database for IBD (CHASE-IBD)

Background:The incidence of inflammatory bowel disease (IBD) is rapidly increasing in China, a vast country with significant geographical differences. The socioeconomic status of Eastern China is significantly higher than that of Western China.Objectives:This study aimed to describe the geographical heterogeneity in the characteristics and management of patients with IBD in both Eastern and Western China.Design:This was a multicenter, cross-sectional study.Methods:Patients with IBD with ages > 18 years up to 18 January 2023 were included in the analysis from the Chinese database for IBD. Logistic regression was used to identify risk factors associated with surgeries among patients with IBD.Results:Among 8305 patients with IBD, the ratio of ulcerative colitis (UC) to Crohn's disease (CD) was 4.13 and 0.33 in Western and Eastern China, respectively. The median age at diagnosis of UC and CD was 40.69 and 28.58 years, respectively. There was a male predominance among patients with UC (54.3%) and CD (68.0%). The two regions exhibited a similar distribution of disease locations in UC. However, Western China had a higher proportion of L2 involvement (30.0% versus 19.1%) and more advanced disease behavior (B2 and B3) (48.8% versus 39.8%) than Eastern China. Patients with IBD in Western China received more 5-aminosalicylic acid and corticosteroids and fewer immunomodulators and biologicals. In terms of surgical risk, Eastern China [versus Western China, odds ratios (OR): 5.36, 95% confidence intervals (CI): 2.96-9.68] was associated with a higher risk of surgery in UC, while Western China (versus Eastern China, OR: 3.39, 95% CI: 2.37-4.86) was associated with a higher risk of surgery in CD.Conclusion:Geographical heterogeneity exists in the disease characteristics and management of IBD in Eastern and Western China. These findings have the potential to guide the formulation of location-specific strategies aimed at enhancing the long-term outcomes of patients with IBD.