What is the threshold for symptomatic response and remission for major depressive disorder, panic disorder, social anxiety disorder, and generalized anxiety disorder?
OBJECTIVE
Symptom-free remission is a goal for treatment in depression and anxiety disorders, but there is no consensus regarding the threshold for determining remission in individual disorders. We sought to determine these thresholds by comparing, in a post hoc analysis, scores on the Clinical Global Impressions scale (CGI) and disorder-specific symptom severity rating scales from all available studies of the treatment of major depressive disorder, panic disorder, generalized anxiety disorder, and social anxiety disorder with the same medication (escitalopram). We also sought to compare the standardized effect sizes of escitalopram for these 4 psychiatric disorders.


METHODS
Raw data from all randomized, double-blind, placebo-controlled, acute treatment studies sponsored by H. Lundbeck A/S (Copenhagen, Denmark) or Forest Laboratories, Inc. (New York, N.Y.), published through March 1, 2004, with patients treated with escitalopram for DSM-IV major depressive disorder (5 studies), panic disorder (1 study), generalized anxiety disorder (4 studies), or social anxiety disorder (2 studies) were compared with regard to the standardized effect sizes of change in CGI score and scores on rating scales that represent the "gold standard" for assessment of these disorders (the Montgomery-Asberg Depression Rating Scale, the Panic and Agoraphobia Scale, the Hamilton Rating Scale for Anxiety, and the Liebowitz Social Anxiety Scale, respectively).


RESULTS
In all indications, treatment with escitalopram showed differences from placebo in treatment effect from 0.32 to 0.59 on the CGI-S and CGI-I and standardized effect sizes from 0.32 to 0.50 on the standard rating scales. There were no significant differences among the different disorders. Moderate to high correlations were found between scores on the CGI and the standard scales. The corresponding standard scale scores for CGI-defined "response" and "remission" were determined.


CONCLUSIONS
Comparison of scores on the standard scales and scores on the CGI suggest that the traditional definition of response (i.e., a 50% reduction in a standard scale) may be too conservative.
Bandelow
Borwin
B
Department of Psychiatry and Psychotherapy, University of Göttingen, Göttingen, Germany. Sekretariat-Bandelow@medizin-uni-goettingen.de
Baldwin
David S
DS
Dolberg
Ornah T
OT
Andersen
Henning Friis
HF
Stein
Dan J
DJ
D001008:Anxiety Disorders / Q000175:diagnosis / Q000188:drug therapy* / Q000523:psychology; D015283:Citalopram / Q000627:therapeutic use*; D003865:Major Depressive Disorder / Q000175:diagnosis / Q000188:drug therapy* / Q000523:psychology; D039721:Diagnostic and Statistical Manual of Mental Disorders; D018572:Disease-Free Survival; D004311:Double-Blind Method; D006801:Humans; D016584:Panic Disorder / Q000175:diagnosis / Q000188:drug therapy / Q000523:psychology; D010698:Phobic Disorders / Q000175:diagnosis / Q000188:drug therapy / Q000523:psychology; D010919:Placebos; D011569:Psychiatric Status Rating Scales / Q000706:statistics & numerical data*; D011594:Psychometrics; D011788:Quality of Life; D016032:Randomized Controlled Trials as Topic; D012107:Research Design / Q000592:standards; D017367:Selective Serotonin Reuptake Inhibitors / Q000627:therapeutic use*; D012720:Severity of Illness Index; D016896:Treatment Outcome
D015283:Citalopram; D010919:Placebos; D017367:Selective Serotonin Reuptake Inhibitors