Straumann, G. 1%, 5%, 9%, and 18%, respectively, for colectomy. The presence of extraintestinal manifestations and extended disease location (at least left-sided colitis) were identified as risk factors for step-up in therapy with systemic corticosteroids, IM, TNF antagonists, calcineurin inhibitors, and surgery. Cigarette smoking at diagnosis was protective against surgery. Conclusions: The presence of extraintestinal manifestations, left-sided colitis, and extensive colitis/pancolitis at the time of diagnosis were associated with use of systemic corticosteroids, IM, TNF antagonists, calcineurin inhibitors, and colectomy during the disease course. value <0.1 were entered into a multivariable logistic regression model. A value <0.05 was considered as statistically significant. RESULTS Characteristics of the Study Population The characteristics of the study population are shown in Table ?Table1.1. A total of 996 patients with UC were included. Median age at the time of inclusion into the SIBDCS was 41 years (interquartile range, 32C52). The disease location at the time of diagnosis was as follows: proctitis in 189 patients (19.0%), left-sided colitis in 239 patients (33.0%), extensive colitis/pancolitis in 381 patients (38.3%), and unknown in 97 patients (9.7%). Median disease duration was 9 (4C16) years. A total of 403 (40.5%) patients presented with extraintestinal manifestations (EIM) (evaluated from the time of enrollment into the SIBDCS until the time of last follow-up visit). Colectomy was performed in 94 patients with UC. Of these, 8 patients (8.5%) suffered from colorectal cancer and 7 (7.4%) from colonic dysplasia. Seventy-nine patients with UC (84%) underwent colectomy due to refractory disease not responding to medication regimens. TABLE 1 Characteristics of the UC Population Open in a separate window Cumulative Proportion of UC-related Drug Use and UC-related Surgery Figures ?Figures11C4 illustrate the cumulative probability of use of the different medications and undergoing UC-related surgery for all disease locations (Fig. ?(Fig.1),1), proctitis only (Fig. ?(Fig.2),2), left-sided colitis only (Fig. ?(Fig.3),3), and extensive/pancolitis only (Fig. ?(Fig.44). Open in a separate window FIGURE 1 Cumulative probability for the use of 5-ASA and/or rectal corticosteroids, systemic corticosteroids, immunomodulators, TNF antagonists, calcineurin inhibitors, and for undergoing surgery for patients with all UC locations examined together. Open in a separate window FIGURE 2 Cumulative probability for use of 5-ASA and/or rectal corticosteroids, systemic corticosteroids, immunomodulators, TNF antagonists, calcineurin inhibitors, and for undergoing surgery for patients with ulcerative proctitis. Open in a separate window FIGURE 3 Cumulative probability for use of 5-ASA and/or rectal corticosteroids, systemic corticosteroids, immunomodulators, DNAJC15 TNF antagonists, calcineurin inhibitors, and for undergoing surgery for patients with left-sided colitis. Open in a separate window FIGURE 4 Cumulative probability for use of 5-ASA and/or rectal corticosteroids, systemic corticosteroids, immunomodulators, TNF antagonists, calcineurin inhibitors, and for undergoing surgery for patients with extensive colitis and pancolitis. In Table ?Table2,2, the point estimates of cumulative probability of UC-specific medication use/undergoing surgery at years 1, 5, 10, and 20 after UC diagnosis stratified according to disease location are shown. Our data indicate that more extensive UC at Aloe-emodin the time of diagnosis was associated with a higher probability of treatment with corticosteroids, TNF antagonists, calcineurin inhibitors, and undergoing UC-related surgery. TABLE 2 Proportion of Patients Treated with Various UC-specific Therapies and/or Undergoing Surgery at Years 1, 5, 10, and 20 After UC Diagnosis Open in a Aloe-emodin separate Aloe-emodin window Systematic Analysis of Risk Factors for Therapy Escalation We further evaluated which factors might be associated with therapy escalation using logistic regression modeling. The following outcomes were analyzed: sex, age at the time of diagnosis, smoking status at the time of diagnosis, IBD family history, the presence of EIM from the time of enrollment into the SIBDCS, disease location at the time of diagnosis, and disease duration (OR per year of disease duration are shown). The results of this analysis are illustrated in Table ?Table3.3. The following factors were found to be positively associated with the use of at least systemic corticosteroids during the disease course in the univariate model (Table ?(Table3):3): the presence of EIM (OR = 2.556, = 0.001), left-sided colitis at the time of diagnosis (OR = 2.207, < 0.001), and extensive/pancolitis at the time of diagnosis (OR = 6.064, < 0.001). We.