Patterns of Comorbidity among DSM-III-R Personality Disorders

Abstract

The aim of this study was to examine patterns of comorbidity among personality disorders (PDs) in a sample of 156 psychiatric inpatients. PDs were assessed with Semistructured Clinical Interview for DSM-III-R Personality Disorders. To determine significant co-occurrence among axis II diagnoses, odds ratio and the percent of co-occurrence of pairs of disorders were calculated. Both statistical methods revealed high rates of comorbidity: significance association was found for 36 pairs of disorders using the percent of co-occurrence, and for 22 pairs of disorders using the odds ratio. These results support the concept of ‘apparent comorbidity’ for most PDs, deriving from conceptual and definitional artifacts or from a ‘state-biasing effect’. In light of these observations, a categorical approach to PDs, resulting in a list of diagnoses, appears useless in psychiatric practice. A dimensional classification is probably better suited for PDs, improving the understanding of personality psychopathology and its clinical implications.

The Prevalence of DSM-IV Personality Disorders in Psychiatric Outpatients

“…Most studies are of inpatients only (40,42) or of inpatients combined with outpatients (12,13,29,41,(44)(45)(46). We are not aware of a study that is comparable to the MIDAS project in which semistructured interviews have been integrated into a community-based outpatient practice.…”

“…Integrating research-quality evaluations into an outpatient practice requires that more obstacles are overcome (25). Diagnostic interviewers in the studies listed in Table 4 included psychiatric residents (12,13,42), trained research interviewers with undescribed levels of experience and professional training (29,41), and psychiatrists with extensive prior experience with semistructured diagnostic interviews (45). The samples also differed in the most frequent axis I disorders and the diagnostic system used.…”

The Brave New World of Personality Disorder-Trait Specified: Effects of Additional Definitions on Coverage, Prevalence, and Comorbidity

“…Within-PD comorbidity rates are high (1) in non-patient as well as patient samples (Zimmerman & Coryell, 1989), (2) using different assessment instruments (Oldham et al, 1992), and (3) across various Western cultures (Marinangeli et al, 2000). This excessive comorbidity undermines the validity and utility of the DSM-5 -II PD diagnostic system, in which the 10 PD criterion sets are intended to reflect “qualitatively distinct clinical syndromes” (APA, 2013, p. 646).…”

Efficacy and cost-effectiveness of an experimental short-term inpatient Dialectical Behavior Therapy (DBT) program: study protocol for a randomized controlled trial

“…In outpatient samples, rates of 9.3 to 18% have been reported, with a pooled rate of 11.9% [5]. Studies of psychiatric inpatient populations have reported rates of BPD at about 40% [9]. …”