Caldeira Daniel, Cazeiro Daniel Inácio, Plácido Rui, Ferreira Filipa, Calé Rita, Pinto Fausto J
Serviço de Cardiologia, Departamento de Coração e Vasos, Centro Hospital Universitário Lisboa Norte (CHULN), Unidade Local de Saude Santa Maria, Centro Académico de Medicina de Lisboa, 1649-035 Lisboa, Portugal.
Laboratory of Clinical Pharmacology and Therapeutics, Faculdade de Medicina, Universidade de Lisboa, 1649-028 Lisboa, Portugal.
Med Sci (Basel). 2025 May 7;13(2):57. doi: 10.3390/medsci13020057.
Placebo-controlled studies are crucial in clinical trials, but the placebo effect can vary across conditions. We aimed to assess the placebo effect in chronic thromboembolic pulmonary hypertension (CTEPH) trials. We conducted a systematic review and included randomized placebo-controlled trials investigating CTEPH interventions. Primary outcomes were the pre-post changes in the 6 min walk test (6MWT) and quality of life in the placebo arms. Secondary outcomes included mean pulmonary artery pressure (mPAP), pulmonary vascular resistance (PVR), cardiac index, and NT-proBNP levels. Meta-analyses were performed using random-effects models. Seven trials with 270 CTEPH patients in placebo arms were analyzed. The average 6MWT change was not significant (-1.31 m; 95%CI -12.49 to +9.79). Quality of life with EQ-5D was not significantly improved (-0.04; 95%CI -0.10 to +0.02). mPAP, PVR, cardiac index, and NT-proBNP also demonstrated non-significant changes with small magnitudes. The placebo effect in CTEPH trials was not statistically significant and had small magnitude but should not discourage the use of placebo-controlled trials where applicable and ethical.
安慰剂对照研究在临床试验中至关重要，但安慰剂效应在不同情况下可能有所不同。我们旨在评估慢性血栓栓塞性肺动脉高压（CTEPH）试验中的安慰剂效应。我们进行了一项系统评价，纳入了调查CTEPH干预措施的随机安慰剂对照试验。主要结局是安慰剂组6分钟步行试验（6MWT）和生活质量的前后变化。次要结局包括平均肺动脉压（mPAP）、肺血管阻力（PVR）、心脏指数和NT-proBNP水平。使用随机效应模型进行荟萃分析。分析了7项试验，安慰剂组中有270例CTEPH患者。6MWT的平均变化不显著（-1.31米；95%CI -12.49至+9.79）。EQ-5D评估的生活质量没有显著改善（-0.04；95%CI -0.10至+0.02）。mPAP、PVR、心脏指数和NT-proBNP也显示出微小的非显著变化。CTEPH试验中的安慰剂效应在统计学上不显著且幅度较小，但在适用且符合伦理的情况下，不应阻碍使用安慰剂对照试验。
