School of Psychology, University of Sydney, Sydney, NSW, Australia.
J Psychopharmacol. 2012 Dec;26(12):1540-7. doi: 10.1177/0269881112458730. Epub 2012 Sep 19.
Patients in clinical practice and participants in clinical trials are warned about side effects that may result from their treatment. Such warnings could lead to placebo-induced side effects if they create an expectation of these effects. We used an experimental model to test this possibility. Undergraduates reporting sleep difficulty received placebo treatment disguised as a hypnotic for one week and were warned about either one or four bogus side effects. Placebo treatment significantly improved sleep difficulty relative to a no treatment control group, as indicated by self-report and by objective outcomes. At the end of the treatment week participants who had been warned about a single side effect showed better recall of this effect than those warned about four side effects. Most importantly, participants tended to report experiencing a side effect they had been warned about, with a trend towards a larger effect in participants warned about one side effect. This evidence for placebo-induced side effects may need to be considered when interpreting data on side effects from clinical trials.
在临床实践中，患者和临床试验的参与者会被告知可能因治疗而产生的副作用。如果这些警告会产生对这些影响的预期，那么它们可能会导致安慰剂引起的副作用。我们使用实验模型来测试这种可能性。报告睡眠困难的本科生接受了为期一周的伪装成催眠药的安慰剂治疗，并被告知一种或四种虚假副作用。与无治疗对照组相比，安慰剂治疗显著改善了睡眠困难，这一点通过自我报告和客观结果得到了证实。在治疗周结束时，被告知单一副作用的参与者比被告知四种副作用的参与者对该副作用的记忆更好。最重要的是，参与者倾向于报告他们被警告过的副作用，而在被告知一种副作用的参与者中，这种趋势更为明显，效应更大。在解释临床试验中副作用的数据时，可能需要考虑这种安慰剂引起的副作用的证据。
