P159 Predictors of complicated disease in Crohn's disease and ulcerative colitis

Background: Several clinical risk factors for a more complicated disease course of Crohn’s disease (CD) and ulcerative colitis (UC) have been identified. We aimed to validate these factors prospectively in newly diagnosed CD and UC patients. Methods: In total, 179 patients were followed for a median (IQR) of 32 (17 46) months. CD and UC were diagnosed in 104 and 79 patients, respectively (54% male, median age 26 years). At diagnosis, 36% of CD patients had ileal (L1), 11% colon (L2) and 53% ileocolonic involvement (L3) and 66% had inflammatory (B1), 16% stricturing (B2) and 18% fistulizing behavior (B3), 34% were active smoking and 83% had elevated C-reactive protein level (CRP >5mg/L). In UC, 27% had proctitis (E1), 21% leftsided (E2) and 52% extensive colitis (E3) at diagnosis, 16% were active smoking and 66% had an elevated CRP. Results: During follow-up, 16 CD patients developed a complication (8 strictures, 12 fistula) after a median of 10 (6 24) months. Risk factors were L1 location (LogRank p = 0.002) and elevated baseline CRP (p = 0.043). Interestingly, none of the 7 patients who started combo therapy within 6 months of diagnosis, developed a complication. In Cox regression multivariate analysis, L1 location was the only predictive factor of complication development [Odds ratio 4.0 (95%CI 1.2 12.9), p = 0.022]. In total, 23 CD patients needed resection after a median of 11 (7 26) months. Risk factors were ileal involvement (p = 0.077), B3 behavior (p = 0.053) and elevated baseline CRP (p = 0.059). In multivariate analysis, B3 behavior was the only factor predicting resection [OR 2.9 (1.0 8.3), p = 0.050].