Dexamethasone suppression test in hospitalized depressed patients with borderline personality disorder.

There is considerable disagreement about the relationship between borderline personality disorder and the affective disorders. The authors report the results of a study of the relationship between dexamethasone suppression and depressive subtype in hospitalized depressed borderline patients. Twenty-three patients met research criteria for unipolar major depressive episode without psychosis of at least moderate severity. Thirteen patients also met criteria for borderline personality disorder. Dexamethasone suppression test (DST) results showed no significant correlation with either melancholia or borderline personality disorder alone. However, of the 13 borderlines, eight failed to suppress and six of those eight were not melancholic. The authors conclude that abnormal response to dexamethasone in nonmelancholic borderlines casts some doubt on the specificity of the DST for melancholia.