Reported weight loss and dexamethasone nonsuppression in depressed patients. A negative study

The effects of dieting and weight loss upon the stimulation of thyrotropin (TSH) by thyrotropin-releasing hormone (TRH) and suppression of cortisol secretion by dexamethasone in men and women

The effects upon basal hormone levels and neuroendocrine responses of a weight reducing diet allowing 1200 kcal daily were determined in male and female volunteers. Thyrotropin (TSH) responses to thyrotropin-releasing hormone (TRH) were unchanged in men but attenuated in women; this effect was associated with a fall in basal TSH in women, not in men. Rates of non-suppression of cortisol in response to oral dexamethasone (1 mg) were unchanged during dieting although basal morning cortisol levels rose in males and females. The implications for the use of the TRH test and the dexamethasone suppression test (DST) in depressive illness are discussed.

The relationship between age and post-dexamethasone cortisol: a test of three hypotheses

Previous studies report that DST nonsuppressors are older than normal suppressors. Data are presented on 188 primary unipolar major depressive inpatients and 35 healthy controls. In males, age appeared to correlate positively with post-dexamethasone cortisols in depressed patients and normal controls, although mean levels were higher in depressives. Female controls showed no consistent relationship between age and post-dexamethasone cortisol. A positive relationship did exist for depressed women. However, the association disappeared when age-of-onset was entered into the model, suggesting that in females early onset may identify a subtype of depression with normal DST suppression.

Psychopathological correlates of plasma cortisol after dexamethasone suppression: a polydiagnostic approach

Seventy-seven consecutively admitted inpatients with depressive syndromes were examined with the Present State Examination and classified according to eight different operational diagnoses of endogenous depression. All patients received a 1.5 mg dexamethasone suppression test (DST). Sensitivity, specificity and the corrected predictive values of DST nonsuppression (50 or more ng/ml at 0800 hr, 1600 hr, or 2300 hr), adjusted to a 50% prevalence of endogenous and nonendogenous depression, varied considerably depending on the diagnostic definition used. The highest predictive value (89.9%) was found with the Taylor-Abrams criteria (sensitivity = 43.9%, specificity = 95.0%), and the lowest predictive value (53.3%) with DSM-III (sensitivity = 37.7%, specificity = 68.1%). Eliminating the patients with dexamethasone levels of less than 2000 pg/ml improved the diagnostic specificity of the DST for most of the eight definitions of endogenous depression. This further indicates that plasma dexamethasone levels should be analyzed in studies designed to explore the diagnostic utility of the DST. A significant, chance-corrected association between DST nonsuppression and the diagnosis of endogenous depression was found with clinical diagnosis (according to the International Classification of Diseases), and for four out of eight operational diagnoses (Newcastle Scale I, Newcastle Scale II, Taylor-Abrams Criteria, and Vienna Research Criteria). For the other diagnoses (Research Diagnostic Criteria, DSM-III, Michigan Discriminant Index, and Hamilton Endogenomorphy Index), no significant association was found. The RDC criterion "early or intermittent awakening" was the only one out of 28 diagnostic criteria tested which was significantly associated with DST nonsuppression.