The impact of personality disorders on treatment outcome of anxiety disorders: best-evidence synthesis.

Thirty-five studies were traced addressing the impact of comorbid personality disorders on treatment outcome of anxiety disorders. The conclusions of this review are based on the best-evidence procedure. We used two selection criteria that studies had to meet to be included in the present review. The study design had to be prospective and a (semi)structured interview had to be used for the assessment of personality disorders. From the fifteen selected studies it cannot be concluded that, in general, personality disorders affect treatment outcome for anxiety disorders negatively. We can only suspect that some personality disorders may have an adverse impact upon treatment outcome in anxiety disorders, and they should be investigated further. For the time being, in clinical practice one has to be cautious in relating personality disorders to less well treatment outcome in axis I anxiety disorders.