Borderline personality disorder (BPD) is fundamentally a syndrome composed of symptoms (primarily of emotional dysregulation) and a number of true personality traits (such as inordinate anger, impulsivity, and a tendency to stress-related paranoid ideation). Whereas schizotypal personality disorder, with its cognitive peculiarities (ideas of reference, odd beliefs, eccentric speech), is closely linked as a genetic condition-"borderline" to the major condition schizophrenia-BPD is less closely linked to bipolar disorder. Some cases of BPD are linked genetically to and are in the "border" of bipolar disorder. But the condition can also arise from adverse post-natal factors: parental cruelty or neglect, or incest. In some BPD patients, both are present: risk genes for bipolar disorder and adverse conditions within the family. The genetic risk is often overlooked. To avoid this, initial evaluations should always include a careful and extensive family history for mood disorders, and should extend out to grandparents, aunts, uncles, and cousins. Where the history suggests a genetic link to bipolar disorder, a mood stabilizer such as lithium or lamotrigine, even in modest doses, may be particularly beneficial, more so than conventional antidepressants. In some patients, ADHD was present in childhood, BPD was diagnosed during or after puberty, and a form of bipolar disorder becomes apparent during their 20s. As for the psychotherapeutic component, the patient's cognitive style and capacity for introspection will help determine whether a primarily expressive (psychoanalytically oriented) technique is preferable or a primarily cognitive-behavioral technique. Flexibility is necessary, since during emotional crises, supportive and limit-setting interventions will be needed, along with psychotropic medications, and where necessary, programs to help combat substance abuse (which is common among patients with BPD).
Keywords: borderline personality disorder; genetic factors; prognostic factors; psychotherapy.