Cortisol, ACTH, and dexamethasone concentrations in a psychogeriatric population.

Cortisol and adrenocorticotrophic hormone (ACTH) were measured at 2 time points before the administration of 1 mg of dexamethasone (day 1) and 1 time point on the following day (day 2). Thirteen severely depressed elderly patients, 15 patients with Alzheimer-type dementia (ATD), and 16 normal controls were studied. Cortisol was markedly elevated in depressed patients compared with the other subjects in day 1 samples. Following dexamethasone, both the depressed and ATD patients showed a similar elevation of cortisol compared with controls. ACTH concentrations were not significantly different between the groups before dexamethasone, but were significantly higher in both depressed and ATD patients after dexamethasone. More depressed patients than ATD patients exhibited hypersecretion of ACTH after dexamethasone. This implies that ACTH is less responsive to glucocorticoid feedback in elderly depressed patients, which may be a factor in causing hypercortisolemia.

The relationship between response to fluoxetine, plasma drug levels, imipramine binding to platelet membranes and whole-blood 5-HT.

1) Thirty-four (34) out-patients with major depressive disorder as defined by Research Diagnostic Criteria were treated with fluoxetine in an open study. 2) All patients received 60 mg daily of the drug for between 18 and 21 days. 3) Of the 28 patients who completed the trial 21 showed improvement and 7 of these showed a marked change. 4) The 7 good responders had a higher fluoxetine:norfluoxetine ratio after three weeks treatment than the remaining patients; 6 of these patients were males. 5) All patients, irrespective of response, showed a decrease in imipramine binding and decrease in whole blood 5-hydroxytryptamine (5-HT) during the period of the study. 6) The response to the drug may be related to metabolism of fluoxetine.

Plasma N-POMC, ACTH and cortisol following hCRH administration in major depression and dysthymia.

The concentrations of plasma N-terminal pro-opiomelanocortin, adrenocorticotropic hormone and cortisol in response to a 14:30 h human corticotrophin releasing hormone (hCRH) stimulation test (1 microgram/kg) were measured in control, major depression and dysthymic subjects. The increases in all three hormones were similar in the depressed groups when compared to the control values. The elevation in cortisol after hCRH was significantly greater in major depression when compared to the dysthymic subjects. The significance of these findings is discussed.

A combined study of cortisol, ACTH and dexamethasone concentrations in major depression. Multiple time-point sampling.

The pathophysiology of hypercortisolaemia in major depression was examined. ACTH was measured using a novel immunoradiometric assay of high specificity and sensitivity. Twenty-eight patients with major depression and 18 control subjects were studied. Blood samples for basal hormone concentration were taken at 09:00, 16:00 and 23:00 on day 1, followed by administration of 1 mg dexamethasone at 23:00. Further samples were taken at 09:00 and 16:00 on day 2. Dexamethasone concentration was measured in day 2 samples and no significant difference was found between the depressed group and control subjects. In the depressed group cortisol concentration was elevated at 23:00 on day 1, and ACTH concentrations were elevated in post-dexamethasone samples. ACTH and cortisol concentrations were not directly correlated in individual patients. The elevated plasma cortisol associated with major depression is not solely mediated by changes in ACTH.

Corticosteroid-binding globulin in depression.

We undertook this study to evaluate the role of plasma free and total cortisol, and corticosteroid-binding globulin (CBG) in depression. Plasma was collected from 15 drug-free depressed patients and 15 age and sex-matched control subjects at 0900 and 2300 and at 1600 following an oral dose of dexamethasone. Depressed patients had elevated concentrations of both free and total cortisol at all time points studied. The binding capacity and affinity of plasma CBG for cortisol was similar in both groups at all times studied. No differences in CBG measures were noted if the depressed subjects were divided into elderly or younger subjects and dexamethasone suppression test (DST) suppressors or non-suppressors.