P660 A Danish cross-sectional study: autoimmune and chronic inflammatory disorders associated with Crohn’s disease
M. Halling*1, J. Kjeldsen1, T. Knudsen2, J. Nielsen3, L. Koch Hansen4
1Odense University Hospital, Department of Gastroenterology, Odense, Denmark, 2Esbjerg Hospital, Dept. of Gastroenterology and Hepatology, Esbjerg, Denmark, 3Odense University Hospital, Department of Clinical Epidemiology, Odense, Denmark, 4Vejle Hospital, Dept. of Gastroenterology and Hepatology, Vejle, Denmark
Crohn’s disease (CD) is an inflammatory bowel disease that affects people all over the world. At least in part, CD is thought to be an autoimmune disease; however, larger population studies have not previously been performed to show that autoimmune and other chronic inflammatory diseases are more frequent in patients with CD. In Denmark, the healthcare system is free, which gives unique patient databases, as they are not influenced by financial status or insurance coverage. Our objective was to examine the risk of well-known autoimmune and chronic inflammatory diseases in all Danish patients with CD compared with matched controls.
We designed a cross-sectional population-based study including all patients alive living in Denmark with diagnoses compatible with CD (International Classification of Disease, ICD8 and ICD10 were used). Diagnoses were obtained from the Danish National Patient Registry, which since 1977 and 1994, have stored information about every contact to the Danish healthcare system, both in-hospital and in outpatient clinics, respectively. All patients with CD were paired with random controls (2:1) from the Danish Civil Registration System matched by age (± 1 year), sex, and county. Statistics were made using STATA13, and results presented as odds ratio and 95% confidence intervals. P < 0.0125 was considered significant because of multiple testing of diseases (Bonferroni).
In total, 13 343 CD patients and 26172 controls were included. Table 1 depicts selected autoimmune and chronic inflammatory diseases in patients with CD compared with matched controls. The results are presented as odds ratios (OR) together with 95% confidence intervals (CI). *p < 0.00125; (*) p = 0.00125–0.05; ns p > 0.05.
In our population-based cross-sectional study, we found increased odds ratios (risk) of common autoimmune and chronic inflammatory diseases in patients with CD compared with matched controls. We believe that our findings are unique because they emphasises the autoimmune, however, complex origin of CD. Importantly, one must be aware of the increased risks when treating patients with CD.