Mental state decoding impairment in major depression and borderline personality disorder: meta-analysis.

BACKGROUND Patients with major depression and borderline personality disorder are characterised by a distorted perception of other people's intentions. Deficits in mental state decoding are thought to be the underlying cause of this clinical feature. AIMS To examine, using meta-analysis, whether mental state decoding abilities in patients with major depression and borderline personality disorder differ from those of healthy controls. METHOD A systematic review of 13 cross-sectional studies comparing Reading in the Mind of the Eyes Test (RMET) accuracy performance of patients with major depression or borderline personality disorder and healthy age-matched controls (n = 976). Valence scores, where reported, were also assessed. RESULTS Large significant deficits were seen for global RMET performance in patients with major depression (d = -0.751). The positive RMET valence scores of patients with depression were significantly worse; patients with borderline personality disorder had worse neutral scores. Both groups were worse than controls. Moderator analysis revealed that individuals with comorbid borderline personality disorder and major depression did better than those with borderline personality disorder alone on accuracy. Those with comorbid borderline personality disorder and any cluster B or C personality disorder did worse than borderline personality disorder alone. Individuals with both borderline personality disorder and major depression performed better then those with borderline personality disorder without major depression for positive valence. CONCLUSIONS These findings highlight the relevance of RMET performance in patients with borderline personality disorder and major depression, and the importance of considering comorbidity in future analysis.