@article{ref1,
title="Initial severity and antidepressant efficacy for anxiety disorders, obsessive-compulsive disorder, and posttraumatic stress disorder: an individual patient data meta-analysis",
journal="Depression and anxiety",
year="2018",
author="de Vries, Ymkje Anna and Roest, Annelieke M. and Burgerhof, Johannes G. M. and de Jonge, Peter",
volume="35",
number="6",
pages="515-522",
abstract="BACKGROUND: It has been suggested that antidepressant benefits are smaller for mild than severe depression. Because antidepressants are also used for anxiety disorders, obsessive-compulsive disorder (OCD), and posttraumatic stress disorder (PTSD), we examined the influence of severity for these disorders. <br><br>METHODS: We used individual patient data of eight trials (3,430 participants) for generalized anxiety disorder (GAD); four trials (1,195 participants) for social anxiety disorder (SAD); four trials (1,132 participants) for OCD; three trials (1,071 participants) for PTSD; and 10 trials (2,151 participants) for panic disorder (PD). Mixed-effects models were used to investigate an interaction between severity and treatment group. <br><br>RESULTS: For GAD and PD, severity moderated antidepressant efficacy. The antidepressant-placebo difference was 1.4 (95% CI: 0.4-2.5; SMD: 0.21) Hamilton Anxiety Rating Scale (HAM-A) points for participants with mild GAD (baseline HAM-A = 10), increasing to 4.0 (3.4-4.6; SMD: 0.45) or greater for severely ill participants (HAM-A ≥ 30). For PD, the difference was 0.4 (0.3-0.6) panic attacks/2 weeks for participants with 10 panic attacks/2 weeks at baseline, increasing to 4.7 (3.0-6.4) for participants with 40. For SAD, OCD, and PTSD, no interaction was found. Across severity levels, the differences were 16.1 (12.9-19.3; SMD: 0.59) Liebowitz Social Anxiety Scale points, 3.4 (2.5-4.4, SMD: 0.39) Yale-Brown Obsessive-Compulsive Scale points, and 10.3 (6.9-13.6; SMD: 0.41) Clinician-Administered PTSD Scale points. <br><br>CONCLUSIONS: Antidepressants are equally effective across severity levels for SAD, OCD, and PTSD. For GAD and PD, however, benefits are small at low severity, and the benefit-risk ratio may be unfavorable for these patients.<br><br>© 2018 Wiley Periodicals, Inc.<p /> <p>Language: en</p>",
language="en",
issn="1091-4269",
doi="10.1002/da.22737",
url="http://dx.doi.org/10.1002/da.22737"
}