When one size doesn’t fit all: Exploring borderline personality subtypes and their nomological networks in a nonclinical population

Borderline personality disorder is a highly heterogeneous condition characterized by substantial variability in symptom presentation across individuals, suggesting the existence of distinct subgroups. While much research has examined these patterns within traditional diagnostic models, few studies have explored borderline subtypes within the Alternative Model for Personality Disorders. Understanding these subgroups is essential, as they may differ in their association with transdiagnostic constructs crucial in the onset and maintenance of borderline personality disorder, namely emotion dysregulation, intolerance of uncertainty, and impulsivity. Using a new digital mental health assessment tool, the Digital Interventions for Psychological and Psychiatric Services (DIPPS), 365 nonclinical participants (mean age = 29.3±12.9) reported their levels of Borderline Criterion B facets along with the aforementioned constructs. Latent Profile Analysis identified five distinct profiles: an adaptive-resilient group with above-average borderline traits (N=106), a normative group with elevated risk-taking (N=89), another with elevated anxiety (N=70), a group with high emotional reactivity but low behavioral disinhibition (N=83), and a final group with both high emotional reactivity and behavioral disinhibition (N=17). These profiles demonstrated consistent nomological networks, with the first group showing below-average levels of the measured constructs and subsequent groups displaying increasing levels of associations, culminating in the last group with the highest impairment. Findings suggest the existence of several borderline subtypes in the nonclinical population with varying severity, each displaying distinct patterns with maladaptive functioning. These results highlight the importance of considering heterogeneity in borderline presentations and support the utility of digital tools like DIPPS for psychological assessment.