A Meta-Analysis of the Efficacy of Pregabalin in the Treatment of Generalized Anxiety Disorder

Objective: Generalized anxiety disorder (GAD) is a chronic anxiety disorder that leads to significant functional impairment and reduced quality of life. Pregabalin is a novel analogue of the inhibitory neurotransmitter gamma amino butyric acid, which has been proposed as a treatment for a range of conditions including GAD. This study examined the efficacy of pregabalin for GAD across published trials, using a meta-analytic method. Method: This study examined the 7 published placebo-controlled trials of GAD using pregabalin, and, using meta-analytic techniques, we calculated the effect size of treatment with pregabalin (compared with placebo) on a total of 1352 people. Results: The overall effect size of pregabalin in the treatment of GAD was Hedges' g = 0.364, with an effect size of 0.349 on psychic anxiety symptoms and of 0.239 on somatic anxiety symptoms. Conclusion: Pregabalin is an efficacious therapy for GAD, although effect sizes are smaller than those from earlier studies. Limitations and future research directions are discussed.