A distinct mechanism for reflux in patients with cystic fibrosis: a study using high resolution manometry-impedance

neoplasia. Cox proportional hazard regression analysis was used to calculate the risk of advanced neoplasia in patients with and without thiopurine or 5-ASA use. Results: A total of 2605 patients with a confirmed IBD diagnosis were included in this study. Of these, 981 patients (38%) used 5-ASA, 315 patients (12%) used thiopurines, 459 patients (18%) used both 5-ASA and thiopurines and 850 patients (33%) used none of these drugs. No statistically significant differences were found for type of IBD, gender, age, duration of IBD and extent of IBD between these groups. Thirty-one patients (1%) developed advanced neoplasia during 16,568 person years of follow-up. Of these, 12 patients (39%) had used 5-ASA, 2 (7%) thiopurines and 1 (3%) both drugs. Increasing age and disease involvement of more than 50% of the colon were associated with an increased risk of developing advanced neoplasia (adjusted hazard ratio (HR) 1.07, 95% confidence interval (CI) 1.04-1.11 and adjusted HR 5.88, 95% CI 2.00-17.3, respectively). Thiopurine use was associated with a significantly decreased risk of developing advanced neoplasia (adjusted HR 0.10, 95% CI 0.01-0.73). 5ASA therapy had also a protective effect on developing advanced neoplasia, but this was not statistically significant (adjusted HR 0.51, 95% CI 0.20-1.26). Conclusion: Thiopurine use protects colitis patients against the development of advanced neoplasia. The effect of 5ASA appeared to be less pronounced.