Thiopurine withdrawal during sustained clinical remission in inflammatory bowel disease: relapse and recapture rates, with predictive factors in 237 patients

Aliment Pharmacol Ther. 2014 Dec;40(11-12):1313-23. doi: 10.1111/apt.12980. Epub 2014 Oct 6.


Background: Thiopurines (azathioprine and mercaptopurine) remain integral to most medical strategies for maintaining remission in Crohn's disease (CD) and ulcerative colitis (UC). Indefinite use of these drugs is tempered by long-term risks. While clinical relapse is noted frequently following drug withdrawal, there are few published data on predictive factors.

Aim: To investigate the success of planned thiopurine withdrawal in patients in sustained clinical remission to identify rates and predictors of relapse.

Methods: This was a multicentre retrospective cohort study from 11 centres across the UK. Patients included had a definitive diagnosis of IBD, continuous thiopurine use ≥3 years and withdrawal when in sustained clinical remission. All patients had a minimum of 12 months follow-up post drug withdrawal. Primary and secondary end points were relapse at 12 and 24 months respectively.

Results: 237 patients were included in the study (129 CD; 108 UC). Median duration of thiopurine use prior to withdrawal was 6.0 years (interquartile range 4.4-8.4). At follow-up, moderate/severe relapse was observed in 23% CD and 12% UC patients at 12 months, 39% CD and 26% UC at 24 months. Relapse rate at 12 months was significantly higher in CD than UC (P = 0.035). Elevated CRP at withdrawal was associated with higher relapse rates at 12 months for CD (P = 0.005), while an elevated white cell count was predictive at 12 months for UC (P = 0.007).

Conclusion: Thiopurine withdrawal in the context of sustained remission is associated with a 1-year moderate-to-severe relapse rate of 23% in Crohn's disease and 12% in ulcerative colitis.

Publication types

  • Multicenter Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Azathioprine / administration & dosage*
  • Azathioprine / therapeutic use
  • C-Reactive Protein / metabolism
  • Colitis, Ulcerative* / drug therapy
  • Crohn Disease* / drug therapy
  • Female
  • Humans
  • Immunosuppressive Agents / administration & dosage
  • Immunosuppressive Agents / therapeutic use
  • Male
  • Mercaptopurine / administration & dosage*
  • Mercaptopurine / therapeutic use
  • Middle Aged
  • Recurrence
  • Retrospective Studies
  • Risk Factors


  • Immunosuppressive Agents
  • C-Reactive Protein
  • Mercaptopurine
  • Azathioprine