The dexamethasone suppression test in schizo-affective depression

Growth hormone and physiological responses to clonidine in depression

Clonidine (1.3 micrograms/kg) was administered to 62 control and 55 depressed patients free of psychoactive drugs for at least 7 days and fasted overnight. Growth hormone (GH), pulse, blood pressure and sedation were measured every 15 min for 1 h before and 2 h after clonidine infusion. GH response did not differ significantly between control and depressed subjects overall or when divided by sex. The systolic hypotensive and sedative responses were blunted in depressed subjects compared with controls; these effects appeared to be secondary to residual antidepressant drugs since the differences were only significant for those depressed subjects with short drug-free intervals. No differences between depressed subjects and controls were seen in diastolic hypotensive or bradycardic responses and no differences in GH, cardiovascular or sedative responses were found between endogenous and non-endogenous depressed subjects.

Age and the dexamethasone suppression test: results from a broad unselected patient population

We examined the relationship between age and postdexamethasone serum cortisol concentration in 676 psychiatric inpatients with a variety of DSM-III diagnoses. Regardless of diagnosis, patients 65 years and older had significantly higher nonsuppression rates than those below age 65 (64% vs. 34%). The correlation between age and cortisol level was moderate, but significant. Aging is associated with increasing nonsuppression rates to dexamethasone, and this change is augmented by an affective disorder diagnosis. Levels of nonsuppression and age-cortisol correlations vary depending on dose of dexamethasone, diagnosis, and gender.

Neuroendocrine challenge studies in puerperal psychoses. Dexamethasone suppression and TRH stimulation

Subjects admitted to hospital with post-partum psychoses were compared with matched normal post-partum controls using two neuroendocrine challenge tests: dexamethasone suppression of cortisol and TRH stimulation of TSH. Post-dexamethasone cortisol levels were significantly elevated. There were less-clear hints of blunting of TSH response. In the small samples there was no obvious association of abnormalities with any particular diagnoses within the range of mania, psychotic depression and schizoaffective disorders.

The incidence of abnormal dexamethasone suppression in schizophrenia: a review and a meta-analytic comparison with the incidence in normal controls

Studies on dexamethasone suppression test (DST) and schizophrenia are reviewed and the incidence of nonsuppression in the group of studies on schizophrenic patients is compared to that in the group of studies on normal controls from a previous review article. The incidence of nonsuppression in schizophrenic patients (26.4%) is significantly higher than that in normal controls (5.0%). There may be a subgroup of schizophrenic patients with an increase in cholinergic functioning. The variance of the nonsuppression rates of DST were also significantly higher in patients with schizophrenia compared to normal controls. This may be due to a heterogeneity of mechanisms that is responsible for the DST non-suppression due to the heterogeneous nature of the diagnosis of schizophrenia. The possible mechanisms of abnormal and varied DST results in schizophrenia are discussed.

Plasma postdexamethasone cortisol levels in schizoaffective disorder

The degree of hypothalamic-pituitary-adrenal (HPA) axis dysregulation in depressed patients with schizoaffective disorder was compared to that seen in patients with major depressive disorder with and without delusional features. The frequency of nonsuppression to dexamethasone was similar for all three diagnostic groups. Maximum postdexamethasone plasma cortisol was greater for delusional depressives, but did not differ between patients with major depressive and schizoaffective disorders. Modest correlations were found between postdexamethasone plasma cortisol levels, severity of illness, age, and recent weight loss, for patients with both major depressive disorder and delusional depression. For schizoaffective patients, associations between postdexamethasone plasma cortisol levels and various measures of severity of illness, but not age and recent weight loss, were found. Although HPA axis dysregulation occurs more frequently in all three of the studied diagnostic groups than in normal individuals, factors contributing to this dysregulation may be qualitatively different for schizoaffective patients.

TRH test and DST in schizoaffective mania, mania, and schizophrenia

The thyrotropin-releasing hormone (TRH) test and the Dexamethasone Suppression Test (DST) were given to 10 patients who met Research Diagnostic Criteria (RDC) for schizoaffective disorder, manic type, 9 who met the criteria for mania, and 27 who met the criteria for schizophrenia. A blunted thyrotropin (TSH) response to TRH was observed in 3 of the 10 schizoaffective manics, 4 of the 9 manics, and 3 of the 27 schizophrenics. Nonsuppression on the DST was observed in 5 of the 10 schizoaffective manics, 2 of the 9 manics, and 2 of 22 schizophrenics. The schizoaffective manic and the manic patients had similar rates of TSH blunting and DST nonsuppression, and these were significantly higher than the rates in the schizophrenic patients. This difference was not attributable to baseline TSH and cortisol levels or to neuroleptic treatment. It is suggested that patients with RDC schizoaffective mania and mania have more disturbance in the hypothalamic-pituitary adrenal and thyroid axes than patients with schizophrenia.

Thyrotropin response to thyrotropin-releasing hormone in RDC schizodepressed men

Biological tests may help clarify the relationships of schizoaffective disorder to both major depressive disorder and schizophrenia. Thyrotropin-releasing hormone (TRH), 500 micrograms i.v., was administered to 14 schizodepressed, 23 schizophrenics, 41 unipolar major depressives (all by RDC) and 45 healthy controls, all males 20-67 years old with no significant differences in age, body height or weight. Results showed no differences in maximal delta TSH (dTSH max) amongst schizoaffective depressed, schizophrenia and healthy control groups (10.1 +/- 1.3, 9.2 +/- 1.1, 9.7 +/- 0.8 microU/ml, means +/- SEM respectively). Mean major depressives' dTSH max was lower than in each of the other three groups (6.2 +/- 0.4 microU/ml, P less than 0.01 for all). Utilizing a less than or equal to 5.0 microU/ml cut-off criterion for blunting, the schizodepressed had 36%, schizophrenics 44%, healthy controls 22% and major depressed 59% blunters (P less than 0.05 from other three groups). Schizodepressed patients appeared significantly different from major depressed but closer to schizophrenics (and healthy controls) on the TRH test.

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.

Response to the dexamethasone suppression test in schizoaffective disorder, depressed type

Response to the dexamethasone suppression test (DST) was tested in 20 patients fulfilling the Research Diagnostic Criteria (RDC) for schizoaffective disorder, depressed type, and in 52 patients meeting RDC for major depressive disorder. Non-suppression was observed in 25% of the schizodepressives and in 40.4% of the depressives. No significant difference between suppressor and non-suppressor schizodepressives was found with respect to demographic, historical and clinical variables. These results do not support the usefulness of the DST for the identification of a homogeneous subtype of schizoaffective disorders.