Distinguishing between adjustment disorder and depressive episode in clinical practice: the role of personality disorder.

Background: There is significant symptomatic overlap between diagnostic criteria for adjustment disorder and depressive episode, commonly leading to diagnostic difficulty. Our aim was to clarify the role of personality in making this distinction.

Methods: We performed detailed assessments of features of personality disorder, depressive symptoms, social function, social support, life-threatening experiences and diagnosis in individuals with clinical diagnoses of adjustment disorder (n=173) or depressive episode (n=175) presenting at consultation-liaison psychiatry services across 3 sites in Dublin, Ireland.

Results: Fifty six per cent of participants with adjustment disorder had likely personality disorder compared with 65% of participants with depressive episode. Compared to participants with depressive episode, those with adjustment disorder had fewer depressive symptoms; fewer problems with social contacts or stress with spare time; and more life events. On multi-variable testing, a clinical diagnosis of adjustment disorder (as opposed to depressive episode) was associated with lower scores for personality disorder and depressive symptoms, and higher scores for life-threatening experiences.

Limitations: We used clinical diagnosis as the main diagnostic classification and generalisability may be limited to consultation-liaison psychiatry settings.

Conclusions: Despite a substantial rate of likely personality disorder in adjustment disorder, the rate was even higher in depressive episode. Moreover, features of likely personality disorder are more strongly associated with depressive episode than adjustment disorder, even when other distinguishing features (severity of depressive symptoms, life-threatening experiences) are taken into account.