Systematic review and meta-analysis of the role of personality disorder in randomised controlled trials of pharmacological interventions for adults with mood disorders

Abstract

Background: Personality disorder (PD) may affect the efficacy of pharmacological interventions for mood disorders, but the extent to which this occurs is uncertain. We aimed to examine the available published evidence concerning the role of PD in pharmacological treatment outcomes of randomised controlled trials (RCTs) for adults with mood disorders (i.e. depressive and bipolar spectrum disorders).

Methods: A systematic search of Cochrane Central Register of Controlled Clinical Trials, PubMed, EMBASE, PsycINFO, CINAHL Complete, and Google Scholar databases was undertaken to identify studies of interest. Data were independently extracted by two reviewers. The Cochrane Risk of Bias tool was used to assess methodological quality and risk of bias. A random effects model was utilised and statistical heterogeneity was assessed using the I² statistic. This systematic review was registered with PROSPERO (CRD42018089279) and the protocol is published.

Results: The search yielded 11,640 studies. Subsequent to removing duplicates, 9657 studies were screened at title and abstract stage and 1456 were assessed at full-text stage. Eighteen studies met criteria for inclusion in this review. Meta-analysis did not reveal a significant difference between groups for treatment outcome (standardised mean difference 0.22 [-0.09, 0.54]; I²: 69%, p=0.17) and remission (risk ratio 0.84 [0.64, 1.11]; I²: 51%, p=0.22).

Limitations: This review was limited by lack of studies on bipolar disorder.

Conclusion: PD comorbidity does not appear to affect treatment efficacy of pharmacological interventions for adults with mood disorders.

Keywords: Personality disorders; bipolar disorder; depression; pharmacological interventions; randomized controlled trial.