Department of Psychiatry, Healthy Mind Lab, Washington University School of Medicine, St. Louis, MO, USA.
Division of Biostatistics, Washington University School of Medicine, St. Louis, MO, USA.
Int J Geriatr Psychiatry. 2020 Jun;35(6):626-632. doi: 10.1002/gps.5279. Epub 2020 Mar 20.
Patient expectations of treatment effects could influence neuropsychological and clinical outcomes in clinical trials of behavioral and lifestyle interventions, which could potentially confound the interpretation of findings. Our aim was to examine whether patient expectancy mediated effectiveness of Mindfulness-Based Stress Reduction (MBSR) for improving cognitive function and clinical outcome.
The present study uses data from a single-blind, multi-site, randomized controlled trial comparing MBSR to a health education attention control in older adults with anxiety and/or depressive disorders and subjective cognitive concerns. Using the Credibility and Expectations Questionnaire, we measured expectancy and perceived credibility of the interventions assigned to patients. Using mediational analysis, we examined the influence of expectancy and credibility on two key outcomes: memory performance and clinical global improvement.
Neither expectancy nor perceived credibility of intervention accounted significantly for MBSR's effectiveness for memory test performance or clinical global improvement.
In this clinical trial, expectancy for improvement did not account for the effectiveness of MBSR on memory performance or clinical outcomes in depressed and anxious older adults. We advise that clinical trials of behavioral and lifestyle interventions for brain health in older adults should measure and test the role of expectancy.
患者对治疗效果的期望可能会影响行为和生活方式干预临床试验中的神经心理学和临床结果，这可能会混淆对研究结果的解释。我们的目的是研究正念减压疗法（MBSR）对改善认知功能和临床结果的有效性是否受到患者期望的影响。
本研究使用了一项单盲、多地点、随机对照试验的数据，该试验比较了 MBSR 与健康教育对照在有焦虑和/或抑郁障碍和主观认知问题的老年患者中的效果。使用可信度和期望问卷，我们测量了分配给患者的干预措施的期望和感知可信度。通过中介分析，我们研究了期望和可信度对两个关键结果的影响：记忆表现和临床总体改善。
期望或干预的感知可信度都没有显著解释 MBSR 对记忆测试表现或临床总体改善的有效性。
在这项临床试验中，改善的期望并没有解释 MBSR 对抑郁和焦虑的老年患者的记忆表现或临床结果的有效性。我们建议，针对老年人大脑健康的行为和生活方式干预临床试验应测量和检验期望的作用。
