Objective: Generalized anxiety disorder (GAD) is associated with impaired role functioning and diminished well-being. The present work examined the efficacy of duloxetine treatment for improving functional outcomes for patients with GAD in 3 independent clinical studies.
Method: Studies were randomized, double-blind, placebo-controlled multicenter trials conducted in adult outpatients with DSM-IV-defined GAD. One study compared 9-week fixed-dose treatment with duloxetine 60 or 120 mg (N = 168 and N = 170, respectively) with placebo (N = 175). The other 2 studies compared 10-week flexible-dose treatment with duloxetine 60-120 mg (study 2, N = 168; study 3, N = 162) with placebo (study 2, N = 159; study 3, N = 161). The main functional outcome measure for each study was the Sheehan Disability Scale (SDS). Additional measures were the Quality of Life Enjoyment and Satisfaction Questionnaire Short Form and the European Quality of Life 5 Dimensions. The 3 studies were conducted in the time period from June 2004 to November 2005.
Results: Duloxetine-treated patients improved significantly more than placebo-treated patients on SDS global functioning (study 1, p <or= .001; studies 2 and 3, p <or= .01) and SDS work, social life, and family/home responsibility scores (p values range from <or= .05 to <or= .001). At treatment endpoint, a greater percentage of duloxetine-treated patients had obtained SDS global functioning scores in the normative range than placebo-treated patients (p values range from <or= .05 to <or= .001). Duloxetine-treated patients also reported greater increases in quality of life, well-being, and health compared with the placebo group on the other functional measures (p values range from <or= .05 to <or= .001).
Conclusions: Duloxetine consistently reduced role functioning disabilities associated with GAD and enhanced patients' quality of life and well-being in 3 independent clinical studies.
Clinical trials registration: ClinicalTrials.gov identifiers NCT00122824 (study 1) and NCT00122850 (study 3). Study 2 was completed prior to the requirement to post trials at initiation and does not have a registration number.