Generalized anxiety disorder (GAD) is a chronic and disabling condition. The aim of this study was to evaluate the effectiveness of low-dose augmentative quetiapine (mean dose=50 mg/day) in patients with GAD and partial/no response to selective serotonin reuptake inhibitors (SSRIs). Twenty patients with GAD and partial/no response to SSRIs were randomized to quetiapine (n=10) or placebo (n=10) for 8 weeks, continuing their treatment with SSRIs. Analyses of variance with repeated measures on Hamilton Anxiety Rating Scale (HAM-A) and Clinical Global Impression (CGIs; severity of illness) were carried out at baseline and after 8 weeks and the number of responders/remitters was computed and compared between the groups. HAM-A scores at baseline were 15.60 (±4.48) in the placebo group and 18.50 (±6.59) in the quetiapine group, and at the end-point, HAM-A scores in the placebo group were 10.40 (±4.88) and 9.20 (±5.86) in the quetiapine group. A significant time-by-treatment effect was found on the HAM-A (F=5.19, P=0.035) and CGIs scores (F=19.60, P<0.001) in favor of the quetiapine group. The number of responders was numerically superior in the quetiapine group (60 vs. 30%) without reaching statistical significance (χ2=1.82, degree of freedom=1, P=0.37, φ=0.30). Remitters were 40% for the quetiapine group versus 20% for the placebo group (χ2=0.95, degree of freedom=1, P=0.63, φ=0.22). Low-dose augmentative quetiapine may be an useful treatment option for patients with GAD and partial/no response to SSRIs. The lack of double-blind conditions and the limited sample size may limit the confidence in the reported results. Larger randomized controlled trials are warranted to confirm these data.
Department of Psychiatry, University of Milan, Fondazione IRCCS Ca'Granda Ospedale Maggiore Policlinico, Milan, Italy
Correspondence to Massimiliano Buoli, MD, Department of Psychiatry, University of Milan, Fondazione IRCCS Ca'Granda, Ospedale Maggiore Policlinico, Via F. Sforza 35, Milan 20122, Italy Tel: +39 02 55035934; fax: +39 02 55033190; e-mail: firstname.lastname@example.org
Received October 31, 2010
Accepted February 7, 2011