Differential Efficacy of Pharmacotherapy for Military Veterans vs. Civilians Diagnosed with PTSD: A Meta-Analysis

Background: Advances in the treatment of PTSD have accelerated over the last decade or so, with both psychological and pharmacological interventions showing efficacy in controlled trials. Evidence supports the SSRI/SNRI class as the front-line pharmacotherapy for PTSD. Anecdotal and clinical reports describe military veterans as more "treatment resistant" though empirical evidence supporting this assertion is sparse. Differences in treatment response between veterans and civilians may logically exist and could reflect the influences of greater severity, chronicity and comorbidity among veterans rather than the effect of primary trauma type. The current study reviews the literature and applies meta-analytic statistical tools to examine the evidence for differential treatment outcomes and potential moderators in veterans and civilians with PTSD.

Method: A systematic review and meta-analysis of randomized, double-blind, placebo-controlled trials of SSRI/SNRI for the acute treatment of PTSD was conducted. The primary effect size measure was the raw difference on the total severity score of the Clinician Administered PTSD Scale. Random effects meta-analysis examining the overall effect size as well as moderator and meta-regressions were conducted using Comprehensive Meta-Analysis v2 software.

Results: Preliminary analyses suggest that the SSRI/SNRI group outcome effects were not statistically different, though substantial heterogeneity of effects and relatively low power were observed. Greater depression severity was associated with a decreased effect size.

Conclusion: The maxim that military veterans with PTSD are more "treatment resistant" compared with civilians was not supported. More SSRI/SNRI RCTs are needed and the substantial heterogeneity in outcomes requires further examination.