COMORBIDITY OF AXIS-I AND AXIS-II DISORDERS

Objective: In light of continuing controversies concerning the DSM-III -R system for diagnosing personality disorders, their construct validi ty, and the assignment of disorders to a particular axis, the authors studied patterns of axis I-axis II comorbidity. Method: Semistructured interviews were used to assess axis I and axis II disorders in 200 in patients and outpatients. Odds ratios were calculated to determine sig nificant comorbidity between classes of current axis I disorders and a xis II personality disorders diagnosed according to two methods and de fined at two diagnostic thresholds. Distributions of personality disor der traits were also compared in patients with and without axis I diso rders. Results: Significantly elevated odds ratios were found for co-o ccurrence of current mood disorders with avoidant and dependent person ality disorders; anxiety disorders with borderline, avoidant, and depe ndent personality disorders; psychotic disorders with schizotypal, bor derline, and dependent personality disorders; psychoactive substance u se disorders with borderline and histrionic personality disorders; and eating disorders with schizotypal, borderline, and avoidant personali ty disorders. These results held when conservative and liberal definit ions of personality disorders were used. Nonspecific axis I and axis I I associations were confirmed for distributions of personality disorde r traits. Conclusions: Significant associations occurred between most axis I classes of disorders and axis II disorders and traits in more t han one cluster. All axis I classes of disorders except mood disorders co-occurred with borderline personality disorder; however, patients w ith mood disorders had elevated levels of borderline traits. When any personality disorder was present, there were significant odds that a m ood, anxiety, psychotic, or eating disorder would also be present; psy choactive substance use disorders, in contrast, significantly co-occur red with borderline and histrionic personality disorders.