Effekte der Erwartungsmodulation auf die viszerale Plazeboanalgesie bei gesunden Frauen

Subtitle: Effects of Expectation in Visceral Placebo Analgesia: A Study in Healthy Women

Article type: Research Article

Authors: Kotsis, Vassilios | Benson, Sven | Reidick, Daniel | Rosenberger, Christina^; | Gizewski, Elke Ruth | Elsenbruch, Sigrid

Affiliations: Inst. für Medizinische Psychologie und Verhaltensimmunbiologie, Universitätsklinikum Essen, Universität Duisburg-Essen | Inst. für Diagnostische und Interventionelle Radiologie und Neuroradiologie, Universitätsklinikum Essen, Universität Duisburg-Essen

Note: [] Korrespondenzadresse: Prof. Dr. Sigrid Elsenbruch, Institut für Medizinische Psychologie und Verhaltensimmunbiologie, Universitätsklinikum Essen, Hufelandstraße 55, 45122 Essen. Tel.: 0201/723-4502, Fax: 0201/723- 5948, E-mail: [email protected]

Abstract: Objectives: This study aimed to assess effects of expectation in placebo analgesia in the context of visceral pain in healthy women. Methods: In N = 21 healthy women visceral pain was induced by rectal distension after determination of individual pain thresholds. All participants were assessed in three conditions in randomized order using a deceptive design. To manipulate the expectation of analgesia, participants were informed they would either receive an intravenous infusion of a highly potent analgesic drug (100% expectation condition), possibly the analgesic drug in a double-blind design (50% expectation condition), or an inert substance, in example sodium chloride (0% expectation condition). In reality, participants received the inert substance in all three conditions. Visceral pain was measured using a 100 mm visual analogue scale (VAS) in all conditions. Additionally, symptoms of anxiety and depression (Hospital Anxiety and Depression Scale) and personality traits (NEO-FFI) were assessed. Results: The manipulation of expectation resulted in significantly decreased perceived pain (p < 0.05, condition effect). Placebo-responders (as defined bymedian split) were characterized by higher trait anxiety. Responders evaluated the rectal stimuli as significantly less painful (p<0.001), less unpleasant (p< 0.001), and less burdening (p < 0.05) compared to non-responders. The magnitude of the placebo response (delta score of VAS scores for 100% versus 0% expectation) was significantly associated with anxiety (r = 0.51, p < 0.05). Conclusion: The expectation to receive a potent medication is sufficient to induce significant placebo analgesia in the context of visceral pain. Anxiety may be a moderator of placebo analgesia. The findings may have clinical implications for the treatment of functional gastrointestinal conditions or in post-operative pain.

Keywords: Placebo, analgesia, visceral pain, anxiety, personality traits

Journal: Zeitschrift für Medizinische Psychologie, vol. 19, no. 3-4, pp. 120-127, 2010