Tratamiento farmacológico del trastorno límite de personalidad

SUMMARY Temperament and character are terms utilized to delineate the participation of biologic and psychosocial factors in the development of normal and disordered personality. At times, biological factors, and in others rearing, education, psychological and social events at an early age are the main determinants. The American Psychiatric Association describes Borderline Personality Disorder (BPD) as characterized by a pattern of interpersonal, self-image and affective instability, as well as notable impulsivity. In this disorder, temperament as an inherited factor plays an important role, as demonstrated by familial studies in which the disorder is more frequently present in the families of probands than non-probands. Other disorders where impulsivity is an outstanding feature, such as antisocial personality disorder and substance abuse, are also frequent in first degree relatives of patients with BPD. Psychological factors, such as sexual abuse during childhood, are particularly high in this disorder. This is believed to generate features such as emotional instability, distrust, and dissociative states. From this point of view, it is possible that BPD is a form of “adaptation” not only psychological and behavioral, but also biological. Changes in the volume of the amygdala and hippocampus have been described in the brain of women abused during childhood, and those with BPD. BPD is frequently present in clinical practice, either or not associated to other psychiatric disorders; it can be found anywhere from 11 to 40.4% according to the setting studied. This incidence is even higher in patients with multiple suicide attempts. The term “borderline” was established when this pathological condition was conceptualized to originate between neurosis and psychosis. However, current understanding of personality is better explained with a psychobiological model based on various dimensions. There is one related to schizophrenia (cognitive-perceptual organization dimension) and others related to mood disorders (mood regulation dimension), impulse control (impulsivity-aggression dimension), and anxiety disorders (anxiety-inhibition dimension). Patients with BPD show persistent disturbance on the four dimensions. The combination of these disturbances, along with specific defense mechanisms and coping strategies, originate the characteristic behaviors of individuals with BPD. Regarding the first dimension (cognitive-perceptual organization), BPD patients manifest paranoid ideation and dissociative symptoms usually under severe stress. It is possible that frontal lobe functioning is compromised due to a reactive dopamine and norepinephrine surge in the prefrontal lobe. The disturbance in the second dimension (mood regulation) is manifested in BPD by rapid mood shifts due to excessive sensitivity to separation, frustration and criticism. Although present in all cluster B personality disorders, mood instability in BPD is responsible for stormy relationships, self-image and self-esteem fluctuations, constant rage and bad temper, physical fights, and feelings of emptiness. This mood instability seems to be related to a serotonin effect on the dopaminergic and noradrenergic systems. Disturbances in the third dimension (impulsivity-aggression) originate a lack of control in the use of alcohol and/or drugs, as well as binge eating, reckless driving, shopping sprees, suicide gesture/attempts, self mutilation, and uncontrollable/inappropri-ate anger. Most studies note the inverse relationship between serotonin levels, and impulsivity, aggression, and self-harm behavior. Finally, abnormalities in the fourth dimension (anxiety-inhibition) manifest as themselves frantic attempts to prevent real or imaginary abandonment. No neurobiological substrate has been proposed in this dimension. The growing evidence of neurobiological basis favors the utilization of pharmacological agents in the treatment of BPD. This paper reviews available publications on controlled clinical trials, hoping to provide a guide in the prescription of psychopharmacological agents to the patient with BPD. These patients can benefit from pharmacological treatment for impulsivity, psychotic states, affective instability and depression.