To investigate if treatment outcome for severely depressed patients depends on their baseline level of anxiety.

Patients with a primary diagnosis of MDD with co-morbid anxiety (HAM-A at least 20) were randomised to 24 weeks of double-blind treatment with fixed doses of escitalopram (20 mg) (n=141) or paroxetine (40 mg) (n=139). Post-hoc analyses of efficacy were based on analysis of covariance (ANCOVA) of change from baseline to endpoint (last observation carried forward, LOCF).

At Week 24, the mean change from baseline in MADRS total scores was 24.1 for escitalopram-treated patients and -21.4 for paroxetine-treated patients (mean difference 2.6, p<0.05). The mean change from baseline in HAM-A total score was 17.4 for escitalopram-treated patients and -15.1 for paroxetine-treated patients at Week 24 (p<0.05). The proportion of remitters (MADRS<=12 and HAM-A<=7) after 24 weeks of treatment was 58.2% (82 out of 141 patients) in the escitalopram group and 44.6% (62 out of 139 patients) in the paroxetine group (p<0.01). Significantly more patients (p<0.01) withdrew from the paroxetine group (31%) than from the escitalopram group (17%). The main AEs leading to withdrawal were nausea (escitalopram versus paroxetine: 1 versus 4), insomnia (2 versus 2), and hyperhidrosis (1 versus 2). There were no statistically significant differences in the incidence of individual adverse events between treatments.

Patients with severe depression together with comorbid anxiety symptoms responded statistically significantly better to treatment with escitalopram 20 mg compared with paroxetine 40 mg, regardless of the severity of anxiety symptoms at baseline.