By definition of the DSM-IV, personality disorders (PD) involve inflexible and maladaptive personality traits that cause significant functional impairment. This impairment implies difficulties in regulating affect, relating to others, achieving goals, and dealing with stress.
Moreover, the use of potentially dysfunctional coping strategies, which matches an overreliance on immature defense mechanisms, is associated with personality disorders. In the light of complexity of the PD diagnostic category, we believe that it is necessary to define the general conditions for their diagnostic, where, in the context of our model, the borderline level of functioning might be among the most important ones.
Personality disorders have a strong impact and a contagious effect on the environment. Their alloplastic defenses and the way they communicate their distress affect the others' responses and have a deleterious effect on the social surrounding. Disharmonious relationships, abuse of children, aggression and violence, increased rates of risk behaviors and substance abuse are frequent consequences of personality disorders, which make their prevention and treatment of a paramount importance to psychiatry.
The origin of personality disorders is multifactorial, and is best understood by the biopsychosocial model, which covers interacting biological, psychological and social risk factors. Most theories suggest that an interaction between an innate biological vulnerability to stress (anxiety, affect regulation) and an invalidating parental environment lead to future personality psychopathology. Traumatic childhood experiences, such as loss, physical and sexual abuse, witnessing domestic violence, were indicated as crucial in numerous studies. Subjects with personality disorders were neglected and "psychologically undernourished" children of disordered parents. Relatively subtle forms of neurological and biochemical dysfunction (which may be sequel of these childhood experiences or innate vulnerabilities) are also of a great importance. Psychological and social stressors would precipitate a transition from the innate vulnerability to overt psychopathology.
D. Lecic-Tosevski, MD, PhD
Institute for Mental Health, School of Medecine, Belgrade