[Efficacy of escitalopram vs paroxetine on severe depression with associated anxiety: data from the "Boulenger" study]

Abstract

Several recent studies have underlined the importance of anxiety in major depressive disorders. It has been shown that anxiety was responsible for worsening of depression and reduction of the efficacy of the antidepressant treatment. While it is well known that SSRI are efficient in treating depression or anxiety disorders, the authors tried to determine the influence of baseline anxiety on the response to SSRI treatment in patients with severe depression receiving either escitalopram or paroxetine. In a 24-week double-blind clinical trial, 459 patients with a primary diagnosis of severe major depressive disorder were randomised to receive escitalopram (20mg) or paroxetine (40mg). Post hoc analyses of efficacy in patients with a baseline HAM-A total score less or equal to 20 (n=171) or greater than 20 (n=280) were based on analysis of covariance. (ANCOVA) (ITT, LOCF). At week 24, the mean change from baseline in MADRS total score was -24.2 for escitalopram-treated patients (n=141) and -21.5 for paroxetine treated patients (n=139) (p<0.05, between both groups) in high baseline anxiety patients (HAM-A>20) and the mean change from baseline in HAM-A total score was -17.4 (escitalopram) and -15.1 (paroxetine) (p<0.05, between both groups). As far as complete remitters (CGI-S=1) after 24-week treatment were concerned, their number was significantly higher with escitalopram in the case of marked baseline anxiety. No difference was shown in the low baseline anxiety group. Looking for the influence of baseline anxiety on SSRI treatment effects, the authors showed that antidepressant efficacy of 20mg escitalopram was better than 40mg paroxetine for patients highly depressed with comorbid anxiety symptoms and that, contrary to paroxetine, escitalopram maintained sustained antidepressant activity in patients featuring increased baseline anxiety levels.