Aetiological risk factors for personality disorders.

Background: Elucidation of aetiological processes leading to development of Axis II disorders is important in category validation and could lead to new treatments.

Aims: To establish aetiological associations between Axis II disorders and specific risk factors.

Method: Male and female subjects (n = 260) in maximum security hospitals and prisons were interviewed to determine DSM-III Axis II and lifetime Axis I diagnoses. Aetiological risk factors were obtained at interview and from case files. Independent statistical associations were established by logistic regression.

Results: Axis II categories were divided into four groups: (a) disorders of character development, secondary to an adverse early environment: antisocial, self-defeating and paranoid; (b) disorders of temperament, secondary to constitutional aetiology: avoidant, dependent, schizoid and schizotypal; (c) a 'mixed' disorder of constitutional and environmental aetiology: borderline; and (d) aetiological associations not established: narcissistic, histrionic, compulsive and passive-aggressive.

Conclusions: The study validates several Axis II categories but challenges the inclusion of others within Axis II of DSM-IV, in particular schizoid, schizotypal, avoidant and borderline personality disorders. The findings have implications for future treatment interventions.