Authors' reply

摘要

We thank Emilio Servera and Jesus Sancho for their comments on our study but have to strongly disagree with several of the points that they raise. The ethical justification for this randomised controlled trial was clearly explained in the paper and eloquently supported by the paper referenced. This study did not deprivepatients of non-invasive ventilation; on the contrary a much greater number received non-invasive ventilation than would otherwise have been the case. The study was done in a centre where patients with amyotrophic lateral sclerosis and respiratory compromise were not routinely referred for non-invasive ventilation. Furthermore, the supervising neurologist was at liberty to refer patients in the standard care arm for non-invasive ventilation when this would have been their normal practice. It has been suggested the trial should have been stopped early. Such action may have resulted in the study failing to answer the questions it was designed to address, negating the contribution of all patients who participated. This would have been both inappropriate and unethical. The data supporting the enthusiastic application of non-invasive ventilation in patients with amyotrophic lateral sclerosis by a minority of clinicians was presented in the paper (reference 5 in the paper). Despite several positive retrospective and non-randomised prospective studies, also cited in the paper, and the opinion of experts, the current position in the UK and other countries is that few patients with amyotrophic lateral sclerosis receive non-invasive ventilation. In our survey of UK practice, we found that 5-5% of patients under review received non-invasive ventilation (2-6-3-5% of all patients with amyotrophic lateral sclerosis). Of 265 neurologists, 172 had not referred any patients for non-invasive ventilation in the preceding year, whereas three neurologists made 30% of all referrals nationally.There is similar variation in practice in the USA. Data from randomised controlled trials are more persuasive in changing practice than lower grades of evidence (cohort studies and expert opinion), and we are surprised by suggestions to the contrary. In common with the Motor Neurone Disease Association, we strongly believe this study will influence the practice of clinicians who in their present practice refer few, if any, patients with amyotrophic lateral sclerosis for non-invasive ventilation.