Comparing the efficacy of benzodiazepines and serotonergic anti-depressants for adults with generalized anxiety disorder: a meta-analytic review

ABSTRACT

Introduction: Generalized anxiety disorder (GAD) is a common form of anxiety disorder. Selective serotonin reuptake inhibitors (SSRIs), serotonin and norepinephrine reuptake inhibitors (SNRIs), and benzodiazepines (BZs) are the most commonly prescribed medications for GAD, but little is known about the relative efficacy of these pharmacological treatments.

Areas covered: This study provides a meta-analytic review of the efficacy of these medications in the treatment of adults with GAD. A comprehensive literature search yielded 54 articles reporting 56 unique studies with 12,655 participants treated with either pill placebo (6,191 participants), SSRIs (16 trials, 2,712 participants), SNRIs (17 trials, 2,603 participants), or BZs (23 trials, 1,149 participants). The overall combined effect size was modest to moderate (Hedges’ g = 0.37, p < 0.0001). Effect sizes decreased significantly over time. SSRIs (Hedges’ g = 0.33) and SNRIs (Hedges’ g = 0.36) demonstrated significantly lower effect sizes than BZs (Hedges’ g = 0.50). These findings were not due to differences in treatment length or publication year.

Expert opinion: The results of this study suggest that the most common forms of pharmacotherapy for adult GAD are moderately effective, with BZs being the most effective drug.

KEYWORDS:

• Generalized anxiety disorder
• GAD
• pharmacotherapy
• benzodiazepines
• SNRI
• SSRI
• medication
• meta-analysis

Acknowledgment

The authors thank J Curtiss from Boston University for his assistance in formulating the statistical analysis plan.

Declaration of interest

SG Hofmann receives financial support from the Alexander von Humboldt Foundation (as part of the Humboldt Prize), as well as grants from the National Institutes of Health (NIH)/National Center for Complementary and Integrative Health (NCCIH) (R01AT007257), NIH/National Institute of Mental Health (NIMH) (R01MH099021, U01MH108168). He is also supported by the James S. McDonnell Foundation 21st Century Science Initiative in Understanding Human Cognition - Special Initiative and receives compensation for his work as an advisor from the Palo Alto Health Sciences and for his work as a Subject Matter Expert from John Wiley & Sons, Inc. and SilverCloud Health, Inc. He also receives royalties and payments for his editorial work from various publishers. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed. One referee declares that they have worked as a consultant for Lundbeck.

Additional information

Funding

This manuscript was not funded.