Breslin N P, Sutherland L R
University of Calgary, Alberta, Canada.
Ital J Gastroenterol Hepatol. 1998 Apr;30(2):226-30.
Crohn's disease is inevitably characterized by episodes of relapse followed by remission. The majority of patients will require at least one resection, unfortunately many will have, at some time in the future, further recurrences requiring additional surgery. Faced with this clinical situation, the physician or surgeon may respond to the therapeutic imperative, i.e., it is better to do something rather than to do nothing at all (i.e., treat the patient). Because of these factors, various authors have suggested that the aminosalicylates or, in certain cases, azathioprine, should be prescribed following resection. From a health system point of view, the case for maintenance therapy must be reviewed against several criteria. First, the therapy to be prescribed must be safe for patients over the long term. For the most part, the safety profile of mesalamine has been well established. There is also increasing evidence for the safety of azathioprine when used in chronic inflammatory diseases such as rheumatoid arthritis. Second, there must be objective evidence of efficacy as assessed by randomized controlled, double-blind trials. To date, several trials have been performed, unfortunately, the most recent have only been reported in abstract form. The results of the trials have been contradictory with a mixture of positive and negative findings. There is a lack of consistency for both the dose response and preferred disease site, the use of placebos, the evaluation of outcome and the statistical analysis. Third, the cost-benefit ratio must favour the therapy. Calculation of the number to reat (NNT) to prevent one recurrence is often helpful. Finally, compliance in a group of patients who often decide on surgery so that they can stop taking medication must be considered. A variety of criteria have been developed to assist in making choices regarding prophylaxis. The first relates to the ease of treating the patient with recurrence. Some patients will respond promptly to conventional therapy and enter remission. Unfortunately, this is not the case for the majority of patients. We lack predictors of response. The second concerns the issue as to whether or not the condition to be prevented, recurrence, is a "serious" event. There would be little discussion of that issue at an IBD meeting! The third considers the possibility of adverse events related to the prophylaxis. Again, there does not appear to be concern related to safety. It is the final criterion regarding effectiveness that balances the argument against a routine recommendation for post-operative maintenance therapy.
克罗恩病不可避免地具有复发期和缓解期交替的特点。大多数患者至少需要进行一次手术切除，不幸的是，许多患者在未来的某个时候会出现进一步复发，需要再次手术。面对这种临床情况，内科医生或外科医生可能会响应治疗的迫切需求，即做点什么总比什么都不做好（即治疗患者）。由于这些因素，许多作者建议在切除术后使用氨基水杨酸类药物，或在某些情况下使用硫唑嘌呤。从卫生系统的角度来看，必须根据几个标准来审视维持治疗的理由。首先，所开的治疗方法必须对患者长期安全。在很大程度上，美沙拉嗪的安全性已得到充分证实。越来越多的证据表明，硫唑嘌呤用于类风湿关节炎等慢性炎症性疾病时也是安全的。其次，必须有通过随机对照双盲试验评估的疗效客观证据。迄今为止，已经进行了多项试验，不幸的是，最近的试验仅以摘要形式报道。试验结果相互矛盾，有正面和负面的发现。在剂量反应、首选疾病部位、安慰剂的使用、结果评估和统计分析方面缺乏一致性。第三，成本效益比必须有利于该治疗方法。计算预防一次复发所需治疗的患者数（NNT）通常会有所帮助。最后，必须考虑一组经常决定进行手术以便能够停药的患者的依从性。已经制定了各种标准来协助做出关于预防的选择。第一个标准涉及治疗复发患者的难易程度。一些患者对传统治疗反应迅速并进入缓解期。不幸的是，大多数患者并非如此。我们缺乏反应的预测指标。第二个标准涉及要预防的情况，即复发，是否是一个“严重”事件。在炎症性肠病会议上，这个问题几乎不会有争议！第三个标准考虑与预防相关的不良事件的可能性。同样，似乎不存在对安全性的担忧。正是关于有效性的最后一个标准平衡了反对术后常规维持治疗建议的论点。
