Previously, we found an anxiolytic effect of ziprasidone augmentation to escitalopram (compared with placebo augmentation) in patients with depression in an 8-week, randomized, double-blind, parallel-group, placebo-controlled trial. Here, we carried out a post-hoc analysis, comparing changes in the Hamilton Depression and Anxiety Rating Scales between patients with anxious depression versus nonanxious depression, using a moderator analysis. Hamilton Depression Rating Scales total change scores from baseline and endpoint were not significantly different (interaction term P=0.91) in patients with anxious depression on ziprasidone augmentation (n=19; -9.1±4.9) or placebo (n=19; -6.1±8.9) versus patients without anxious depression on ziprasidone (n=52; -5.5±6.7) or placebo (n=49; -2.3±4.5). There was a trend toward statistical significance (interaction term P=0.1) in favor of patients without anxious depression for a difference in Hamilton Anxiety Rating Scale total change scores from baseline to endpoint [patients with anxious depression on ziprasidone augmentation (n=19; -2.7±5.3) or placebo (n=19; -3.3±5.8) versus patients without anxious depression on ziprasidone (n=51; -3.9±6.6) or placebo (n=44; -0.9±4.7)]. Ziprasidone augmentation was equally efficacious in treating depression in patients with versus without anxious depression. However, the observed anxiolytic effect for patients with higher anxiety was not clinically significant.
Trial registration: ClinicalTrials.gov NCT00633399.