title: Influence of a Suggestive Placebo Intervention on Psychobiological Responses to Social Stress: A Randomized Controlled Trial.
abstract: We tested the hypothesis that a suggestive placebo intervention can reduce the subjective and neurobiological stress response to psychosocial stress. Fifty-four healthy male subjects with elevated levels of trait anxiety were randomly assigned in a 4:4:1 fashion to receive either no treatment (n = 24), a placebo pill (n = 24), or a herbal drug (n = 6) before undergoing a stress test. We repeatedly measured psychological variables as well as salivary cortisol, alpha-amylase, and heart rate variability prior to and following the stress test. The stressor increased subjective stress and anxiety, salivary cortisol, and alpha-amylase, and decreased heart rate variability (all P < .001). However, no significant differences between subjects receiving placebo or no treatment were found. Subjects receiving placebo showed increased wakefulness during the stress test compared with no-treatment controls (P < .001). Thus, the suggestive placebo intervention increased alertness, but modulated neither subjective stress and anxiety nor the physiological response to psychosocial stress.
authors.affiliation: Charité University Medical Center, Berlin, Germany frank.zimmermann@charite.de.
authors.forename: Frank
authors.initials: F
authors.lastname: Zimmermann-Viehoff
authors.affiliation: Charité University Medical Center, Berlin, Germany.
authors.forename: Nico
authors.initials: N
authors.lastname: Steckhan
authors.affiliation: Ludwig-Maximilians University, Munich, Germany.
authors.forename: Karin
authors.initials: K
authors.lastname: Meissner
authors.affiliation: Charité University Medical Center, Berlin, Germany.
authors.forename: Hans-Christian
authors.initials: HC
authors.lastname: Deter
authors.affiliation: Technische Universität Dresden, Dresden, Germany.
authors.forename: Clemens
authors.initials: C
authors.lastname: Kirschbaum
mesh_terms: D000328:Adult; D001008:Anxiety Disorders / Q000188:drug therapy*; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D006854:Hydrocortisone / Q000032:analysis; D008297:Male; D010919:Placebos / Q000494:pharmacology / Q000627:therapeutic use*; D012463:Saliva / Q000737:chemistry / Q000187:drug effects / Q000201:enzymology; D012920:Social Behavior Disorders; D013315:Stress, Psychological / Q000188:drug therapy*; D055815:Young Adult; D000516:alpha-Amylases / Q000032:analysis
chemical_list: D010919:Placebos; D000516:alpha-Amylases; D006854:Hydrocortisone
keywords: anxiety; cortisol; heart rate variability; placebo effect; psychosocial stress; salivary alpha-amylase