An Individual Meta-Analysis of Psychological Treatments for Mood and Personality Disorders Using the Severity Diagnostic System of ICD-11.

In 30 seconds

This individual patient meta-analysis examined whether ICD-11 personality-disorder severity was associated with short-term outcomes in 1,384 patients from four randomised trials of psychological treatments, mainly cognitive-behavioural, versus standard controls. Across 12–24 months, greater personality pathology tracked with greater mood symptom burden. Improvement in anxiety was significantly smaller among patients with moderate or severe personality disorder than among those without personality disorder; depressive symptoms showed no consistent corresponding pattern. Social function improved across the studies, while treatment effects were small and did not differ significantly.

Key findings

• Mood symptom burden showed a linear trend across personality severity levels, from least in normal personality to greatest in severe personality disorder.
• Anxiety improvement was significantly smaller with moderate or severe personality disorder than with no personality disorder.
• Depressive symptoms did not show the same pattern, except in one trial.
• Social function improved in all studies; treatment effects were small and not significantly different.

Why it matters

The findings suggest that personality dysfunction across the severity spectrum, including sub-syndromal difficulty, is relevant to mood symptoms and social functioning. Considering personality severity may therefore help clinicians interpret symptom burden and expected outcomes during psychological treatment, while the inconsistent depression findings and small treatment effects argue against assuming a uniform impact across outcomes.

What to keep in mind

Personality status was assessed using a proxy ICD-11 classification in the four trials, and treatment effects were small and not significantly different.