PLASMA DEXAMETHASONE CONCENTRATION AND CORTISOL RESPONSE DURING MANICEPISODES

Background: Despite the widespread study of the dexamethasone suppress ion test (DST) in patients diagnosed with major depression, it has bee n less well studied during manic and mixed states of bipolar disorder. Methods: Cortisol response to the administration of 1 mg of dexametha sone was studied in 44 patients diagnosed bipolar disorder, manic (n = 37) or mixed (n = 7). Dexamethasone levels and cortisol responses wer e compared between these groups. Four patients initially meeting crite ria for bipolar disorder, mixed, and 7 patients initially meeting crit eria for bipolar disorder, manic, all of whom were characterized as DS T nonsuppressors, were retested after remission. Results: Dexamethason e levels were lower and cortisol levels higher in those patients diagn osed bipolar disorder, mixed. An inverse correlation was found between log-transformed dexamethasone levels and log-transformed cortisol lev els at 3 PM (r = -.619, p less than or equal to .001) and 10 PM (r = - .501, p less than or equal to .001). In those subjects retested after remission, dexamethasone levels were higher and cortisol levels lower than during the manic and mixed states. Conclusions: Disturbances in t he hypothalamic-pituitary-adrenal axis are observed frequently during mixed states of bipolar disorder, but are also not uncommon in purely manic episodes. These changes appear to be stare dependent and revert with treatment. (C) 1998 Society of Biological Psychiatry.