Introduction Azathioprine is well established for the maintenance of remission in patients with Crohn’s disease and 87% patients on maintenance therapy are able to reduce steroid consumption. However, azathioprine is less effective at treating disease recurrence and seven patients need to be treated to prevent one recurrence (1). Intolerance to azathioprine occurs in almost a third of patients and it has been proposed that the intolerance to azathioprine is a poor prognostic marker that may predispose patients to a more aggressive disease course.
Methods A cross sectional study was performed using the Milton Keynes Hospital IBD database to compare outcomes of patients that were azathioprine intolerant and those that were azathioprine tolerant. A descriptive analysis of clinical features and outcomes of these two groups was performed.
Results 141 patients were included for analysis of which 24.8% were intolerant to azathioprine. The median age of azathioprine intolerant patients was 47 and 31.4% were male. In the azathioprine tolerant cohort, the median age was 36 and 41.5% were male. Azathioprine was not tolerated due to gastrointestinal side effects in 53.6%, neurological effects (depression/headaches/vertigo) in 17.9%, deranged LFTs in 17.9% and the arthralgia/neutropenia and cutaneous side effects making up the remaining cases.
Conclusion Azathioprine is a drug that is not tolerated in nearly a quarter of Crohn’s disease patients and this effect demonstrated a sex bias towards females. Patients who were intolerant to azathioprine were not more likely to undergo surgery or to have more strictures or fistulas. However, azathioprine-intolerant patients were considerably more likely to have more active disease, to require monoclonal antibody therapy and steroids. Compared to patients who are able to use azathioprine, for every 100 patients who are intolerant, 24 less will be in remission and 20 more will have moderate to severe disease. We conclude that patients with azathioprine intolerance will have poorer symptom control, but does not predispose to a more aggressive disease course.
Disclosure of Interest None Declared.
Pearson D, May G, Fick G, Sutherland L. Azathioprine for maintenance of remission in Crohn’s disease. Cochrane Database of Systematic Reviews