Manifestations of personality impairment severity: comorbidity, course/prognosis, psychosocial dysfunction, and 'borderline' personality features.

Impairment in personality functioning (briefly, personality impairment) is the core pathology in personality disorder (PD) and an essential indicator of PD-severity. It also is a difficult construct to define and assess. We argue that personality-impairment severity is a latent construct that can be modeled with four indicators: within-PD comorbidity, problematic course/prognosis of both PD and comorbid clinical syndromes, PD-associated psychosocial dysfunction, and features of DSM-5-II borderline PD (BPD). Our literature review documents interrelations among the first three indicators, and studies of PD structure reveal a higher order factor of general PD severity marked most strongly by BPD features. Together, these findings indicate that BPD features may be helpful in the important tasks of defining and assessing personality-impairment severity.