Biological markers in borderline personality disorder: new perspectives.

There has been much research on the biological markers of borderline personality disorder (BPD) in the last three years. The Dexamethasone Suppression Test, the Thyrotropin-Releasing Hormone Test and sleep studies no longer indicate that BPD is related to depression, although there is probably an affective subgroup. There may be evidence that some subgroups of BPD overlap with schizophrenia. An extensive analysis of serotonin studies provides exciting new directions for understanding suicidal, aggressive and especially impulsive traits.