The TRH test in patients wih borderline personality disorder.

Fifteen patients with a primary diagnosis of borderline personality disorder were studied with the thyrotropin-releasing hormone (TRH) test. Twelve carried the additional diagnosis of depression, substance abuse, or both. A blunted thyroid-stimulating hormone (TSH) response to TRH was found in seven patients, two of whom were neither depressed nor had the additional diagnosis of depression and/or substance abuse. TSH blunting was unrelated to such factors as thyroid status, serum cortisol, weight, height, or body surface. Since TSH blunting occurs in about 25% of patients with major depression but not in schizophrenia, the findings suggest that some patients with borderline personality disorder share a neuroendocrine abnormality with some affective disorder patients.