National Cooperative Crohn's Disease Study: Factors determining recurrence of Crohn's disease after surgery

Records of the 569 patients in the National Cooperative Crohn's Disease Study (NCCDS) were analyzed to determine the interval from onset of symptoms to surgery, the incidence of reoperation after each surgery for Crohn's disease, and the influence of surgical intervention, type of surgery, and site of disease upon recurrence of Crohn's disease. Life-table methods were used to calculate recurrence intervals and rates. Reoperation was accepted as indicating recurrence. The cumulative probability of surgery for Crohn's disease in this group of patients was 78% at 20 yr after onset of symptoms. Although comparisons of recurrence rate after first and after second complete resection yielded no statistically significant difference, the data suggest a higher recurrence rate after the second surgery. Bypass surgery was followed by the highest reoperation rate. The time from onset of symptoms to the first operation for Crohn's disease was shortest for patients with ileocolitis, longer for those with disease involving only small bowel, and longest for those with colon-only disease. These differences were statistically significant. Thus, the site of involvement of Crohn's disease is a major determinant of outcome after surgical intervention. Seventy-three patients (13%) underwent abdominal operations for Crohn's disease during their participation in the NCCDS. They were equally divided among the four treatment groups, indicating that none of the drug regimens tested altered the incidence of surgery.