Glucocorticoids. Mood, memory, and mechanisms

Elevated circulating levels of glucocorticoids are associated with psychiatric symptoms across several different conditions. It remains unknown if this hormonal abnormality is a cause or an effect of the psychiatric conditions. For example, the hypercortisolemia observed in a subset of patients with depression may have a direct impact on the symptoms of depression, but it is also possible that the hypercortisolemia merely reflects the stress associated with depression. Further, rather than causing depression, hypercortisolemia could represent a homeostatic attempt to overcome glucocorticoid resistance. Each of these possibilities will be considered, and correlational and causal evidence will be reviewed. This article will focus on the relationships between glucocorticoids and psychiatric symptoms in Cushing's syndrome, major depression, and steroid psychosis/steroid dementia, as well as the effects of exogenously administered glucocorticoids in normal volunteers. Similarities and differences in the relationship of glucocorticoid hormones to psychiatric symptoms in these conditions will be reviewed. Possible mediators of glucocorticoid effects on the brain and behavior, as well as possible "pro-aging" effects of glucocorticoids in certain cells of the body, will be reviewed. The article concludes with a conceptual model of glucocorticoid actions in the brain that may lead to novel therapeutic opportunities.

The use of mifepristone in the treatment of neuropsychiatric disorders

Mifepristone is a potent glucocorticoid and progesterone receptor antagonist. The pathophysiology of a number of neuropsychiatric disorders implicates abnormalities in glucocorticoid function. These include mood disorders such as psychotic major depression and bipolar depression. In addition, cognitive disorders such as Alzheimer's disease might also be partially mediated by abnormalities in the hypothalamic-pituitary-adrenal axis. Preliminary studies suggest that mifepristone might have a role in the treatment of a number of neuropsychiatric disorders.

Challenges in the treatment of depression with psychotic features

Major depression with psychotic features (MDpsy), a disorder with considerable morbidity and mortality, is more common than is generally realized and is a most difficult form of depression to treat. Patients with MDpsy exhibit more frequent relapses and recurrences and have increased use of services, greater disability, and a poorer clinical course when compared with nonpsychotically depressed patients. Patients with MDpsy demonstrate distinct biological abnormalities in studies of the hypothalamic-pituitary-adrenal (HPA) axis, dopaminergic activity, enzyme studies, brain imaging, electroencephalogram sleep profiles, and measures of serotonergic function when compared with nonpsychotic depression. The social and occupational impairment in MDpsy has been hypothesized to be secondary to subtle cognitive deficits caused by the higher cortisol levels frequently observed in MDpsy patients. Several studies support a relationship between bipolar disorder and MDpsy, particularly in young-onset MDpsy. The most efficacious treatments for MDpsy include the combination of an antidepressant and an antipsychotic, amoxapine, or electroconvulsive therapy. Atypical antipsychotic medications may have particular relevance for the treatment of MDpsy because of the potential for reduced risk of extrapyramidal side effects and tardive dyskinesia, as well as antipsychotic and possibly antidepressant qualities. Based on the observations that MDpsy patients exhibit marked dysregulation of the HPA axis and elevated cortisol levels, several antiglucocorticoid strategies have been employed to treat MDpsy patients. Many questions regarding the acute and long-term treatment of MDpsy remain for future studies to address.

Stress hormone-related psychopathology: pathophysiological and treatment implications

Stress is commonly associated with a variety of psychiatric conditions, including major depression, and with chronic medical conditions, including diabetes and insulin resistance. Whether stress causes these conditions is uncertain, but plausible mechanisms exist by which such effects might occur. To the extent stress-induced hormonal alterations (e.g., chronically elevated cortisol levels and lowered dehydroepiandrosterone [DHEA] levels) contribute to psychiatric and medical disease states, manipulations that normalize these hormonal aberrations should prove therapeutic. In this review, we discuss mechanisms by which hormonal imbalance (discussed in the frameworks of "allostatic load" and "anabolic balance") might contribute to illness. We then review certain clinical manifestations of such hormonal imbalances and discuss pharmacological and behavioural treatment strategies aimed at normalizing hormonal output and lessening psychiatric and physical pathology.

Treatment of depression with antiglucocorticoid drugs

OBJECTIVE

The theoretical and empirical rationales for the potential therapeutic use of antiglucocorticoid agents in the treatment of depression are reviewed.

METHOD

Individual case reports, case series, open-label, and double-blind, controlled trials of the usage of cortisol-lowering treatments in Cushing's syndrome and major depression are evaluated and critiqued.

RESULTS

In each of the 28 reports of antiglucocorticoid treatment of Cushing's syndrome, antidepressant effects were noted in some patients; the largest two series document a response rate of 70% to 73%. Full response, however, was at times erratic and delayed. Across the 11 studies of antiglucocorticoid treatment of major depression, some degree of antidepressant response was noted in 67% to 77% of patients. Antidepressant or antiobsessional effects of antiglucocorticoid augmentation of other psychotropic medications have also been noted in small studies of patients with treatment-resistant depression, obsessive-compulsive disorder, and schizoaffective disorder or schizophrenia.

CONCLUSIONS

These promising results with antiglucocorticoid treatment must be interpreted cautiously because of the small sample sizes and heterogeneity of the studies reviewed, the bias favoring publication of positive results, and the open-label nature of most of the studies. Although definitive controlled trials remain to be conducted, there is a consistent body of evidence indicating that cortisol-lowering treatments may be of clinical benefit in select individuals with major depression and other hypercortisolemic conditions.

Antiglucocorticoid treatment of depression: double-blind ketoconazole

BACKGROUND

Hypercortisolemia is frequently observed in major depression but its pathophysiologic significance is unknown. In patients in whom hypercortisolism contributes to depressive symptomatology, antiglucocorticoid agents should have antidepressant effects.

METHODS

Twenty medication-free depressed patients (eight of whom were hypercortisolemic and twelve of whom were not) received either the cortisol biosynthesis inhibitor, ketoconazole (400-800 mg/d p.o.) or placebo for 4 weeks in a double-blind manner, and behavioral ratings were performed weekly.

RESULTS

Ketoconazole, compared to placebo, was associated with improvements in depression ratings in the hypercortisolemic, but not in the non-hypercortisolemic patients. The hormonal changes seen (decreased dehydroepiandrosterone and testosterone levels and increased pregnenolone and pregnenolone-sulfate levels) are consistent with enzymatic blockade of C17,20-lyase, 11-hydroxylase, and 17-hydroxylase. Ketoconazole was generally well tolerated with no occurrence of significant side effects or laboratory abnormalities.

CONCLUSIONS

This small-scale double-blind study suggests that antiglucocorticoids have antidepressant activity in hypercortisolemic depressed patients. The data are consistent with a causal role of adrenocortical dysfunction in some depressed patients and suggest the need for larger-scale trials.

Double-blind treatment of major depression with dehydroepiandrosterone

OBJECTIVE

This study was designed to assess possible antidepressant effects of dehydroepiandrosterone (DHEA), an abundant adrenocortical hormone in humans.

METHOD

Twenty-two patients with major depression, either medication-free or on stabilized antidepressant regimens, received either DHEA (maximum dose = 90 mg/day) or placebo for 6 weeks in a double-blind manner and were rated at baseline and at the end of the 6 weeks with the Hamilton Depression Rating Scale. Patients previously stabilized with antidepressants had the study medication added to that regimen; others received DHEA or placebo alone.

RESULTS

DHEA was associated with a significantly greater decrease in Hamilton depression scale ratings than was placebo. Five of the 11 patients treated with DHEA, compared with none of the 11 given placebo, showed a 50% decrease or greater in depressive symptoms.

CONCLUSIONS

These results suggest that DHEA treatment may have significant antidepressant effects in some patients with major depression. Further, larger-scale trials are warranted.

Glucocorticoid medication, memory and steroid psychosis in medical illness

Steroid psychosis, including associated cognitive changes, is infrequent with short-term low-dose GC treatment, especially if only major objectively discernible effects are assessed. With long-term or high-dose treatment, however, or if milder subjectively discernible symptoms are also assessed, the incidence may be quite high. In lupus cerebritis, the differentiation between cognitive difficulties secondary to the underlying illness, which might warrant more aggressive GC treatment, versus those secondary to GC treatment itself, which might warrant dosage reduction, may be problematic, but certain guidelines have been proposed. Although GCs are widely prescribed and represent a clinically important class of medication, their deleterious effects may also be considerable. Glucocorticoids have prominent effects on central nervous system biochemistry and electrophysiology, and recent reports suggest they make certain hippocampal neurons more vulnerable to a variety of metabolic insults. Indeed, the clinical literature reviewed here is consistent with a disruption of hippocampus-dependent memory function (perhaps in conjunction with other areas of dysfunction), although in most cases the disruption is relatively mild and, in the vast majority, if not all cases, is reversible. From a clinical prospective, it is important to discuss potential neuropsychiatric side effects with patients before prescribing GC treatment. A greater understanding of the risk factors for experiencing SP and of its underlying mechanisms will lead to more informed clinical decision making and to a greater understanding of the role exogenous, and perhaps endogenous, GCs play in human cognition and behavior.

Dehydroepiandrosterone (DHEA) treatment of depression

Dehydroepiandrosterone (DHEA) and its sulfate, DHEA-S, are plentiful adrenal steroid hormones that decrease with aging and may have significant neuropsychiatric effects. In this study, six middle-aged and elderly patients with major depression and low basal plasma DHEA f1p4or DHEA-S levels were openly administered DHEA (30-90 mg/d x 4 weeks) in doses sufficient to achieve circulating plasma levels observed in younger healthy individuals. Depression ratings, as well as aspects of memory performance significantly improved. One treatment-resistant patient received extended treatment with DHEA for 6 months: her depression ratings improved 48-72% and her semantic memory performance improved 63%. These measures returned to baseline after treatment ended. In both studies, improvements in depression ratings and memory performance were directly related to increases in plasma levels of DHEA and DHEA-S and to increases in their ratios with plasma cortisol levels. These preliminary data suggest DHEA may have antidepressant and promemory effects and should encourage double-blind trials in depressed patients.

Management of psychotic, treatment-resistant depression

As there are no controlled studies on approaches to patients with treatment-resistant psychotic depression many questions remain to be answered. Those that seem worthy of high priority include (1) the efficacy of novel antipsychotic agents (e.g., clozapine, risperidone) for acute and maintenance treatment; (2) the efficacy of newer antidepressant agents such as the SSRIs and nefazodone plus neuroleptic medications; (3) decision trees to delineate the second and third lines of treatment when the first treatment is ineffective; (4) the comparative efficacy of bilateral versus unilateral ECT; (5) the length of time patients should be maintained on medications (which is of particular importance in the case of neuroleptic agents with their potential to cause tardive dyskinesia); (6) the optimal dose of neuroleptic agent for acute treatment; (7) the optimal length of time for medication trials; (8) the use of antidepressant medications during ECT treatments; (9) the importance of the sequence in which TCAs and neuroleptic agents are administered; (10) the delineation of the clinical characteristics of responders to medication versus ECT treatments; and (11) the role of antiglucocorticoid strategies. The answers to these questions would provide clinicians with important tools to treat patients with psychotic depression, an illness that all too frequently can become treatment-resistant.

Novel strategies for treatment-resistant depression

This article describes a highly selective constellation of the more unique strategies for managing the treatment-resistant patient. In light of the often-devastating toll that treatment-resistant depression takes on an individual's life, it behooves us to continue the search for more effective strategies for those patients that fail more traditional interventions. As each successive move down the treatment algorithm flowchart becomes necessary, the risk/benefit ratio may shift toward less well-substantiated, but still biologically informed, strategies. Although some of the more unusual treatments described in this article represent minimally charted territories, the more promising techniques are deserving of further careful exploration.

Time course of the corticosteroid-dopaminergic interaction during metyrapone and dexamethasone administration

Recent studies performed with depressed patients and normal subjects suggest that corticosteroids may alter dopaminergic activity. We measured the time course of the interaction between corticosteroid and plasma homovanillic acid (HVA) levels in 10 young healthy subjects after the administration of 2 mg of dexamethasone in session 1 and after the administration of 4.5 g of metyrapone in session 2. Plasma levels of adrenocorticotropic hormone (ACTH), 11-desoxycortisol, cortisol, HVA, and prolactin (PRL) were measured at 08:00, 09:00, 12:00, 15:00, and 16:00 h on a baseline day and during both drug-administration sessions. Dexamethasone administration resulted in a significant decrease in plasma levels of ACTH, 11-desoxycortisol, and cortisol at all time points and to a significant decrease in PRL secretion in the early morning. Plasma HVA levels were unchanged after dexamethasone administration. Metyrapone administration resulted in a significant decrease in cortisol levels and a significant increase in ACTH and 11-desoxycortisol levels. Plasma HVA levels were significantly increased in the early morning, while PRL levels were unaltered. These results are discussed in relation to the neurochemical and behavioral changes associated with steroid administration and interpreted with regard to a possible association between HVA and PRL in the effects of corticosteroids on dopaminergic activity.

Differential diagnosis and treatment of steroid-induced affective syndromes

The differential diagnosis of hypercortisolemia is complex, particularly when the clinician must distinguish Cushing's syndrome (CS) from major depression. The present clinical case history demonstrates that by means of physical and laboratory examinations, the psychiatrist can make the initial differentiation, in consultation with medical specialists. The use of the corticotropin-releasing factor (CRF) stimulation test may be especially helpful in distinguishing Cushing's disease (CD) from major depression, though there is some degree of "overlap" in results. This suggests that these disorders may lie along a continuum of hypothalamopituitary dysfunction.

The psychotropic effects of inhibitors of steroid biosynthesis in depressed patients refractory to treatment

Twenty patients, diagnosed as suffering from treatment-resistant major depression, were treated with one or more drugs that decrease corticosteroid biosynthesis. Nine were psychotic, 11 nonpsychotic. Seventeen completed the treatment (8 psychotic, 9 nonpsychotic); 13 responded (5 psychotic, 8 nonpsychotic; 11 responded completely (i.e., a drop in the Hamilton Depression Scale of at least 50%, to < or = 15), and 2 responded partially. The mean age of the responders (45.2 +/- 12.6 years) did not differ significantly from that of the nonresponders (48.7 +/- 12/3). Data were analyzed in the following categories; (1) the presence or absence of psychosis, (2) response or nonresponse to treatment, and (3) the drug(s) used (aminoglutethimide, ketoconazole, or a combination of either of these with metyrapone). The patients improved over time on the Hamilton Depression Scale independent of the medication used. Responders demonstrated improvement in mood, insomnia, anxiety, diurnal variation, paranoia and obsessive compulsiveness. Nonpsychotics responded better than psychotics.