Disentangling depressive personality disorder from avoidant, borderline, and obsessive-compulsive personality disorders

Several studies have found that 3 personality disorders (PDs) tend to share moderate rates of comorbidity with depressive PD: avoidant, borderline, and obsessive-compulsive. This study sought to evaluate the diagnostic criteria of each disorder in an effort to understand where areas of overlap may occur and to modify criteria sets where reasonable to reduce any degree of overlap. One thousand two hundred psychiatric outpatients were interviewed with the Structured Interview for DSM-IV Personality Disorders. The highest degree of comorbidity was observed between avoidant PD and depressive PD. Logistic regression analyses indicated that 2 criteria—avoidant criterion 5 and depressive criterion 2—could be removed from the diagnostic criteria sets and reduce the rates of overlap by as much as 15%. A factor analysis of the criteria of all 4 PDs indicated that there is a common clustering of many of the symptoms of avoidant, borderline, depressive, and obsessive-compulsive PDs and that borderline symptoms tend to cluster together most consistently. Avoidant and obsessive-compulsive personality symptoms clustered in ways that may reflect a problem of how to engage with others, suggestive of an approach-avoidance conflict. Depressive PD symptoms clustered in a way suggestive of problems with anger that is directed toward oneself and others. The factor analysis results suggest that an organization of symptoms around themes of conflict may provide useful ways of understanding the personality patterns of these 4 disorders.