Comparing the interpersonal profiles of obsessive-compulsive personality disorder and avoidant personality disorder: Are there homogeneous profiles or interpersonal subtypes?

Previous studies have shown that individuals with personality disorder (PD) suffer from significant interpersonal distress. Some PDs, such as avoidant personality disorder (AvPD), have been characterized with a clear homogeneous interpersonal profile. Other PDs, such as obsessive-compulsive personality disorder (OCPD), have shown significant heterogeneity rather than a distinct profile. Our study aimed to compare these two PDs and determine their interpersonal profiles. Analyses included 43 patients with OCPD and 64 with AvPD recruited in 2 clinical trials. They completed the Inventory of Interpersonal Problems at baseline (Alden, Wiggins, & Pincus, 1990). Structural summary and circular statistic methods were used to examine group interpersonal profile. Cluster analysis was used to identify subtypes within the OCPD and AvPD samples. The AvPD sample demonstrated a homogeneous interpersonal profile placed in the socially avoidant octant of the circumplex. In contrast, the OCPD group exhibited a heterogeneous interpersonal profile, with two subtypes on opposite sides of the circumplex: (a) "aggressive" (i.e., vindictive-domineering) and (b) "pleasing" (i.e., submissive-exploitable). Both clusters demonstrated homogeneous, prototypical, and distinct interpersonal profiles. Our findings show that individuals with either OCPD or AvPD exhibit significant interpersonal distress. Although AvPD may be inherently an interpersonal PD, OCPD cannot classified into one homogenous profile, but rather two distinct interpersonal subgroups. The heterogeneity may be explained by the presence of interpersonal subtypes. Detection of subtypes can inform future research on treatment targets as well as personalized interventions, tailored to patients' specific interpersonal difficulties. (PsycInfo Database Record (c) 2020 APA, all rights reserved).