RESUMO
To alleviate anti-cancer treatment burden in advanced breast cancer, patient-clinician communication strategies based on nocebo-effect mechanisms are promising. We assessed distinct/combined effects on psychological outcomes (e.g. anxiety; main outcome) and side-effect expectations of (1) nocebo information about the (non)pharmacological origin of side effects, and (2) clinician-expressed empathy through reassurance of continuing support. Furthermore, we explored whether information and empathy effects on side-effect expectations were mediated by decreased anxiety. In a two-by-two experimental video-vignette design, 160 cancer patients/survivors and healthy women watched one of four videos differing in level of nocebo information (±) and empathy (±). Regression and mediation analysis were used to determine effects of information/empathy and explore anxiety's mediating role. Anxiety was not influenced by empathy or information (Stai-state: p = 0.295; p = 0.390, VAS p = 0.399; p = 0.823). Information improved (specific) side-effect coping expectations (p < 0.01). Empathy improved side-effect intensity expectations (p < 0.01 = specific; p < 0.05 = non-specific/partial) and specific side-effect probability expectations (p < 0.01), and increased satisfaction, trust, and self-efficacy (p < 0.001). No mediating effects were found of anxiety on expectations. Mainly empathy, but also nocebo information improved psychological outcomes and-mainly specific-side-effect expectations. Exploring the power of these communication elements in clinical practice is essential to diminish the anti-cancer treatment burden in advanced breast cancer.
