Subject expectations of treatment effectiveness and outcome of treatment with an experimental antidepressant.
OBJECTIVE
To evaluate the association between treatment expectations and response in a 9-week, single-blind experimental antidepressant treatment study.


METHODS
Twenty-five adult subjects meeting DSM-IV criteria for major depressive disorder with Hamilton Rating Scale for Depression (HAM-D) scores of >/= 17 completed a treatment trial using the experimental antidepressant reboxetine. Following a 1-week placebo lead-in, subjects received single-blind treatment for 8 weeks with reboxetine 8 to 10 mg/day. During the screening visit, subjects were asked to self-rate their expectations of the effectiveness of the study medication. Forced-choice responses were "not at all effective," "somewhat effective," or "very effective." Response to treatment was defined as a final HAM-D score of </= 10 at the end of the 9-week trial. Data were collected from October 1999 to July 2001.


RESULTS
Subjects with a higher pretreatment expectation of medication effectiveness had a greater likelihood of response. Of the subjects who reported an expectation that the medication would be very effective, 90.0% (N = 9) responded to treatment, while only 33.3% (N = 5) of those who reported expecting medication to be somewhat effective responded to treatment (chi(2) = 7.819, p <.005). There was no association between the level of depression severity, duration of current episode, number of prior episodes, or basic demographic factors and treatment outcome.


CONCLUSIONS
These findings indicate that individuals with high baseline expectations of improvement demonstrate a significantly higher level of response to reboxetine than those with lower expectations of improvement with treatment. The data in this study suggest that a subject's expectation of efficacy is associated with the outcome of experimental antidepressant treatment.
Krell
Heather V
HV
Laboratory of Behavioral Pharmacology, UCLA Neuropsychiatric Institute, and the Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine at UCLA, Los Angeles, CA 90024-1759, USA. hkrell@mednet.ucla.edu
Leuchter
Andrew F
AF
Morgan
Melinda
M
Cook
Ian A
IA
Abrams
Michelle
M
D000293:Adolescent; D000328:Adult; D000368:Aged; D000928:Antidepressive Agents / Q000627:therapeutic use*; D001294:Attitude to Health; D018592:Cross-Over Studies; D003866:Depressive Disorder / Q000175:diagnosis / Q000188:drug therapy* / Q000523:psychology*; D015507:Drugs, Investigational / Q000627:therapeutic use*; D005260:Female; D006304:Health Status; D006801:Humans; D008297:Male; D008875:Middle Aged; D009025:Morpholines / Q000627:therapeutic use*; D010919:Placebos; D011569:Psychiatric Status Rating Scales; D000077593:Reboxetine; D012044:Regression Analysis; D016037:Single-Blind Method; D016896:Treatment Outcome
D000928:Antidepressive Agents; D015507:Drugs, Investigational; D009025:Morpholines; D010919:Placebos; D000077593:Reboxetine