Journal Article

Challenges Establishing the Efficacy of Exercise as an Antidepressant Treatment: A Systematic Review and Meta-Analysis of Control Group Responses in Exercise Randomised Controlled Trials

Richards, Justin, Schuch, Felipe B., Rosenbaum, Simon, Stubbs, Brendon, Ussher, Michael, Vancampfort, Davy, Ward, Philip B.

2016

Overview

Background Whilst previous meta-analyses have demonstrated that control group responses (CGRs) can negatively influence antidepressant efficacy, no such meta-analysis exists in exercise randomised controlled trials (RCTs). Objective The aim of this study was to conduct a systematic review and meta-analysis investigating CGRs and predictors in control groups of exercise RCTs among adults with depression. Methods Three authors acquired RCTs from a previous Cochrane review (2013) and conducted updated searches of major databases from January 2013 to August 2015. We included exercise RCTs that (1) involved adults with major depressive disorder (MDD) or depressive symptoms; (2) measured depressive symptoms pre- and post-intervention using a validated measure [e.g. Hamilton Depression Scale (HAM-D)]; and (3) included a non-active control group. A random effects meta-analysis calculating the standardised mean difference (SMD) together with 95 % confidence intervals (CIs) was employed to determine CGR. Results Across 41 studies, 1122 adults with depression were included [mean (SD) age 50 (18) years, 63 % female]. A large CGR of improved depressive symptoms was evident across all studies (SMD −0.920, 95 % CI −1.11 to −0.729). CGRs were elevated across all subgroup analyses, including high quality studies ( n  = 11, SMD −1.430, 95 % CI −1.771 to −1.090) and MDD participants ( n  = 18, SMD −1.248, 95 % CI = −1.585 to −0.911). The CGR equated to an improvement of −7.5 points on the HAM-D (95 % CI −10.30 to −4.89). In MDD participants, increasing age moderated a smaller CGR, while the percentage of drop-outs, baseline depressive symptoms and a longer control group duration moderated a larger CGR (i.e. improvement) ( p  < 0.05). Conclusion In order to demonstrate effectiveness, exercise has to overcome a powerful CGR of approximately double that reported for antidepressant RCTS.

• Publisher: Springer International Publishing,Springer Nature B.V
• Subject: Antidepressants / Control Groups / Depressive Disorder - therapy / Exercise Therapy / Female / Humans / Male / Medicine / Medicine & Public Health / Mental depression / Metabolic disorders / Middle Aged / Psychotherapy / Randomized Controlled Trials as Topic / Sports Medicine / Systematic Review