Low-dose azathioprine is effective in maintaining remission among Chinese patients with Crohn’s disease

Abstract

BackgroundAzathiopurine (AZA) is efficacious for maintenance remission of Crohn’s disease (CD) at the standard dose of 2.0-2.5 mg/kg for Caucasian. It has been reported that the lower dose (1.0-2.0 mg/kg) in some Asian countries was as effective as the standard dose. In the present study we analyzed the efficacy of <1.0 mg/kg AZA in maintaining remission for Chinese patients.MethodsThe clinical data of all CD patients were reviewed from 1993 to December 2012. The patients who initiated AZA treatment and were followed for ≥ 2 years with complete medical data were included. We divided the patients into two groups according to their initial dose: <1.0 mg/kg group and 1.0-2.0 mg/kg group.ResultsAmong 77 patients, 39 (50.6%) started treatment with <1.0 mg/kg AZA and 38 (49.4%) with 1.0-2.0 mg/kg. The mean dose of <1.0 mg/kg group remained under 1.0 mg/kg at 6, 12 and 24 months, even if the doses were adjusted according to efficacy and tolerance. The remission rate in patients of <1.0 mg/kg group was significantly higher than that in those of 1.0-2.0 mg/kg group (P = 0.025). A dose of <1.0 mg/kg AZA was more commonly associated with male gender, older age, heavier body weight and L1 location. Adverse events were observed in 21 of 77 patients (27.3%) and no significant difference in occurrence of adverse events or leucopenia between two groups.Conclusions<1.0 mg/kg AZA was effective as 1.0-2.0 mg/kg in maintaining remission among Chinese patients with CD.

Standard‐dose versus low‐dose azathioprine in the treatment of Crohn's disease: A prospective randomized study

“…retrospectively studied 178 CD patients and found that AZA at 1.24 ± 0.16 mg/kg per day might be an appropriate dose for Chinese CD patients. Wu et al . enrolled 77 CD patients and suggested that AZA <1.0 mg/kg was as effective as that at 1.0–2.0 mg/kg in maintaining remission.…”

“…Patients who stopped AZA treatment for fear of adverse effects, no response (or thought to be non‐responded), recurrence or surgery were not included in the studies. Wu et al . found that the doses in patients who did not achieve remission were significantly higher than those in patients who did, which means that bias existing in these retrospective studies cannot be ignored.…”

“…7 Chinese consensus published in 2012 recommends that sufficient dosage and duration of AZA should be given in treating CD patients. 15 12 found that the doses in patients who did not achieve remission were significantly higher than those in patients who did, which means that bias existing in these retrospective studies cannot be ignored. A well-designed, prospective study to explore the appropriate dose of AZA for Asian patients would be extremely helpful.…”

“…Some researchers reviewed the medical records of patients treated with AZA at different doses and suggested that a lower dose (e.g. 1.0 mg/kg per day) might be more suitable for Asian patients in maintaining remission, despite the retrospective design of the studies. A lower dose of AZA may result in non‐response, recurrence or even surgery in some patients and such patients should not have been recruited in the studies.…”

“…Zhou et al13 retrospectively studied 178 CD patients and found that AZA at 1.24 ± 0.16 mg/kg per day might be an appropriate dose for Chinese CD patients. Wu et al12 enrolled 77 CD patients and suggested that AZA <1.0 mg/kg was as effective as that at 1.0-2.0 mg/kg in maintaining remission. Kim et al 14 analyzed 122 IBD patients treated with AZA and concluded that 1.35 mg/kg was as effective as 2.25 mg/kg.…”