Background: Considerable research has been devoted to the hypothalamic-pituitary-adrenal (HPA) axis in depression, but relatively little attention has been given to intensive monitoring of hormone secretion over time. Such research is potentially important because the HPA axis has prominent circadian and ultradian periodicity. Comparison of depressed patients with and without psychotic features is also important because HPA axis abnormalities may be especially pronounced in psychotic depressed patients.
Methods: Eleven patients with psychotic major depression (PMD patients), 38 patients with nonpsychotic major depression (NPMD patients), and 33 healthy control subjects, all drug free, were studied. Patients with PMD and NPMD were outpatients recruited primarily by advertisement. Subjects were admitted to a General Clinical Research Center and had blood drawn through an intravenous line for determination of cortisol and corticotropin (ACTH) levels every hour for 24 hours.
Results: Among NPMD patients, the 24-hour cortisol amplitude was significantly (P =.02) reduced in comparison with control subjects, while ACTH indices did not differ between NPMD patients and the control group. Among PMD patients, the ACTH 24-hour mean was significantly (P =.03) increased compared with controls, while PMD patients and the control group did not differ significantly in cortisol indices.
Conclusion: In the population studied, PMD and NPMD patients have distinct profiles of HPA axis dysregulation.