TRH STIMULATION AND DEXAMETHASONE SUPPRESSION IN BORDERLINE PERSONALITY-DISORDER

The link between borderline personality disorder (BPD) and affective d isorders is controversial. The dexamethasone suppression test (DST) an d the thyrotropin-releasing hormone (TRH) stimulation test, which are useful in the study of affective illness, might help to elucidate this possible link, This report assessed these endocrine rests in a sample of 20 borderline patients without a concomitant diagnosis of major de pression (but showing depressive symptoms) in comparison to a group of sex- and age-matched patients with major depressive disorder (MDD) wi thout BPD. Only 5 of our BPD patients were DST nonsuppressors compared to 13 MDD patients at a threshold of 50 mu g/L. With a threshold of D elta max TSH < 5 mu U/mL following TRH, I BPD patient showed a blunted TSH response compared to 9 MDD patients. BPD patients displayed signi ficantly less perturbed tests. These results show no evidence of an en docrine biological link between BPD and the MDD. The depressive sympto ms observed in BPD patients might not have the same biological substra tes as those found in patients with MDD.