Influence of a positive family history on the clinical course of inflammatory bowel disease

Background and aims: Previous studies on the difference in phenotypes and disease course between familial and sporadic inflammatory bowel disease (IBD) have been controversial, although family history is considered to increase the risk of developing IBD. Methods: The influence of family history on phenotype and disease course of IBD was analysed in 2805 Korean patients with Crohn's disease (CD) and 3266 with ulcerative colitis (UC). Familial IBD was defined as the existence of one or more first-, second- and/or third-degree relatives affected with CD or UC. Results: A positive family history of IBD was noted in 191 patients with CD (6.8%) and 212 patients with UC (6.5%). In the patients with CD, the probability of anti-TNF use was higher in the familial cases than in the sporadic cases (56.3 vs 43.4%, respectively, at 10 years, p = 0.019). When analysed after excluding patients who had undergone intestinal resection within 1 year of diagnosis, the cumulative probability of intestinal resection was higher in the familial cases than in the sporadic cases (55.0 vs 32.2%, respectively, at 10 years; p = 0.007). In multivariate analysis, family history was an independent risk factor for the time to first intestinal resection in patients with CD (hazard ratio: 1.61, 95% confidence interval: 1.13-2.29; p = 0.009). In patients with UC, younger age at diagnosis and more females were observed in the familial cases (p < 0.001). Conclusions: The present study suggests the possibility of a more aggressive clinical course of CD in familial compared with sporadic cases.