Efficacy and tolerability of benzodiazepines versus antidepressants in anxiety disorders: a systematic review and meta-analysis

Abstract

Background: Placebo-controlled trials showed that both benzodiazepines (BDZ) and antidepressant drugs (AD) are effective in treating anxiety disorders. However, in the last years a progressive shift in the prescribing pattern from BDZ to newer AD has taken place. The aim of this systematic review and meta-analysis is to analyze whether controlled comparisons support such a shift.

Methods: CINHAL, the Cochrane Library, MEDLINE, PubMed and Web of Science were searched from inception up to December 2012. A total of 22 studies met the criteria for inclusion. They were mostly concerned with tricyclic antidepressants (TCA; 18/22) and involved different anxiety disorders. In order to reduce clinical heterogeneity, only the 10 investigations that dealt with the comparison between TCA and BDZ in panic disorder were submitted to meta-analysis, whereas the remaining papers were individually summarized and critically examined.

Results: According to the systematic review, no consistent evidence emerged supporting the advantage of using TCA over BDZ in treating generalized anxiety disorder (GAD), complex phobias and mixed anxiety-depressive disorders. Indeed, BDZ showed fewer treatment withdrawals and adverse events than AD. In panic disorder with and without agoraphobia our meta-analysis found BDZ treatments more effective in reducing the number of panic attacks than TCA (risk ratio, RR = 1.13; 95% CI = 1.01-1.27). Furthermore, BDZ medications were significantly better tolerated than TCA drugs, causing less discontinuation (RR = 0.40; 95% CI = 0.20-0.57) and side effects (RR = 0.41; 95% CI = 0.34-0.50). As to newer AD, BDZ trials resulted in comparable or greater improvements and fewer adverse events in patients suffering from GAD or panic disorder.

Conclusions: The change in the prescribing pattern favoring newer AD over BDZ in the treatment of anxiety disorders has occurred without supporting evidence. Indeed, the role and usefulness of BDZ need to be reappraised.