Philipps-Universität Marburg, Department of Clinical Psychology and Psychotherapy, 35037 Marburg, Germany.
Philipps-Universität Marburg, Department of Differential Psychology and Personality Research, 35037 Marburg, Germany.
Compr Psychiatry. 2023 Nov;127:152431. doi: 10.1016/j.comppsych.2023.152431. Epub 2023 Oct 14.
Placebo and nocebo responses are modulated by the treatment expectations of participants and patients. However, interindividual differences predicting treatment expectations and placebo responses are unclear. In this large-scale pooled analysis, we aim to investigate the influence of psychological traits and prior experiences on treatment expectations.
This paper analyses data from six different placebo studies (total n = 748). In all studies, participants' sociodemographic information, treatment expectations and prior treatment experiences and traits relating to stress, somatization, depression and anxiety, the Big Five and behavioral inhibition and approach tendencies were assessed using the same established questionnaires. Correlation coefficients and structural equation models were calculated to investigate the relationship between trait variables and expectations.
We found small positive correlations between side effect expectations and improvement expectations (r = 0.187), perceived stress (r = 0.154), somatization (r = 0.115), agitation (r = 0.108), anhedonia (r = 0.118), and dysthymia (r = 0.118). In the structural equation model previous experiences emerged as the strongest predictors of improvement (β = 0.32, p = .005), worsening (β = -0.24, p = .005) and side effect expectations (β = 0.47, p = .005). Traits related to positive affect (β = - 0.09; p = .007) and negative affect (β = 0.04; p = .014) were associated with side effect expectations.
This study is the first large analysis to investigate the relationship between traits, prior experiences and treatment expectations. Exploratory analyses indicate that experiences of symptom improvement are associated with improvement and worsening expectations, while previous negative experiences are only related to side effect expectations. Additionally, a proneness to experience negative affect may be a predictor for side effect expectation and thus mediate the occurrence of nocebo responses.
安慰剂和反安慰剂效应受参与者和患者的治疗预期调节。然而，预测治疗预期和安慰剂反应的个体差异尚不清楚。在这项大规模的汇总分析中，我们旨在研究心理特征和先前经验对治疗预期的影响。
本文分析了来自六项不同安慰剂研究的数据（总计 n=748）。在所有研究中，使用相同的既定问卷评估了参与者的社会人口统计学信息、治疗预期和先前的治疗经验以及与压力、躯体化、抑郁和焦虑、大五人格和行为抑制与趋近倾向相关的特征。计算相关系数和结构方程模型，以研究特质变量与预期之间的关系。
我们发现副作用预期与改善预期之间存在较小的正相关（r=0.187），与感知压力（r=0.154）、躯体化（r=0.115）、激动（r=0.108）、快感缺失（r=0.118）和心境恶劣（r=0.118）相关。在结构方程模型中，先前的经验是改善（β=0.32，p=0.005）、恶化（β= -0.24，p=0.005）和副作用预期（β=0.47，p=0.005）的最强预测因素。与积极情绪（β= -0.09；p=0.007）和消极情绪（β=0.04；p=0.014）相关的特质与副作用预期相关。
这项研究是第一项大规模分析，旨在研究特征、先前经验和治疗预期之间的关系。探索性分析表明，症状改善的经验与改善和恶化的预期相关，而先前的负面经验仅与副作用预期相关。此外，体验负面情绪的倾向可能是副作用预期的预测因素，并因此介导反安慰剂反应的发生。
