Clarifying interpersonal heterogeneity in borderline personality disorder using latent mixture modeling

Area of Science:

• Psychology
• Psychiatry
• Clinical Psychology

Background:

• Borderline personality disorder (BPD) is characterized by significant interpersonal difficulties.
• Previous research indicates considerable heterogeneity in the interpersonal profiles associated with BPD.

Purpose of the Study:

• To investigate interpersonal inhibitions and excesses in a large sample of individuals with BPD using the Inventory of Interpersonal Problems-Circumplex (IIP-C).
• To identify distinct interpersonal classes within BPD and examine their relationship with clinical features.

Main Methods:

• Utilized IIP-C scale scores from a sample of 255 individuals with significant borderline pathology.
• Employed latent class analysis to identify homogeneous interpersonal classes.
• Examined the association between BPD symptom counts, interpersonal distress, and identified classes.

Main Results:

• BPD symptom counts were not directly related to the primary dimensions of the IIP-C but were associated with generalized interpersonal distress.
• Latent class analysis revealed six distinct interpersonal classes: Intrusive, Vindictive, Avoidant, Nonassertive, and moderate/severe Exploitable.
• These classes demonstrated significant differences in clinically relevant features, including antisocial behaviors, self-injury, and suicide attempts.

Conclusions:

• The findings highlight the clinical utility of the interpersonal circumplex model in understanding BPD heterogeneity.
• The identified interpersonal classes offer a more nuanced view of BPD's interpersonal dysfunction.
• These classes have implications for developmental and nosological models of BPD, suggesting targeted therapeutic approaches.