The correlation of dexamethasone suppression test and thyrotropin-releasing hormone test results in different subtypes of depression

TSH response to I.V. TRH and suppression of cortisol secretion by dexamethasone were studied in 51 depressive inpatients. There was no significant relationship between the results on both tests, considering blunted TSH responses to TRH and nonsuppression on the DST. Both tests were not complementary in identifying various subgroups of depression as far as the predictive value of a positive result on either or both tests is concerned. Methodological and clinical issues regarding these markers are briefly discussed.