Endoscopic and clinical variables that predict sustained remission in children with ulcerative colitis treated with infliximab

Abstract

Background & aims: We aimed to identify early clinical, laboratory, and endoscopic factors associated with sustained remission in children with ulcerative colitis (UC) treated with infliximab.

Methods: We performed a post hoc analysis of data collected from 51 children (6-17 years old) with moderate-to-severe UC treated with infliximab for 1 year in the T72 clinical trial. The primary outcome was steroid-free remission at weeks 30 and 54 of treatment, which was based on patient and physician assessments. We compared the ability of the Pediatric UC Activity Index (PUCAI, a noninvasive clinical index), levels of C-reactive protein (CRP), and mucosal healing to predict which patients would be in steroid-free sustained remission after 1 year of treatment.

Results: Week 8 PUCAI scores best predicted which patients would be in steroid-free remission after 1 year of treatment; 9 of 17 patients who had PUCAI scores <10 points were in sustained remission (53%), compared with 4 of 20 who had PUCAI scores ≥10 (20%) (P = .036). Mucosal healing at week 8 was associated with steroid-free remission at 1 year, but this did not reach significance; 7 of 16 patients with mucosal healing were in remission after 1 year (44%), compared with 6 of 21 without mucosal healing (29%) (P = .34). The area under the receiver operating characteristic curve values for association with steroid-free sustained remission were 0.70 for the PUCAI (95% confidence interval [CI], 0.53-0.88), 0.56 for mucosal healing (95% CI, 0.36-0.76), and 0.44 for level of CRP (95% CI, 0.24-0.65). By using a multivariable logistic regression model, the week 8 PUCAI was the only factor associated with steroid-free remission at 1 year (P = .038). PUCAI-defined remission had a high degree of concordance with complete mucosal healing at week 8 (33% of patients were in remission according to the PUCAI vs 31% with mucosal healing).

Conclusion: On the basis of a post hoc analysis of data from the T72 clinical trial on the effect of infliximab in pediatric patients with UC, the PUCAI was no less predictive of sustained remission than mucosal healing at week 8, and both were superior to CRP level. Routine endoscopic evaluation in children with UC who are in complete clinical remission (ie, PUCAI <10 points) may not be necessary.

Keywords: AUROC; C-reactive protein; CI; CRP; IBD; IQR; MH; PGA; PUCAI; PaGA; Pediatric UC Activity Index; Predicting Response to Therapy; Prognosis; ROC; UC; confidence interval; interquartile range; mucosal healing; patient global assessment; physician global assessment; receiver operating characteristic; ulcerative colitis.