Spontaneous afternoon plasma cortisol in depression

Catechol-O-methyltransferase Val158Met polymorphism associates with affect and cortisol levels in women

Introduction

We tested the extent to which the catechol-O-methyltransferase (COMT) Val158Met polymorphism is associated with affective state and evening cortisol levels. We limited our study to women as previous research suggests that the link between COMT genotype and psychological health is entangled by sex differences.

Materials and Methods

The participants were assessed on measures of anxiety, mood disturbance, depressive symptomatology, and perceived stress. We also evaluated participants on a quality of life measures that included two emotion domains and two physical domains (physical health and environment).

Results

We found that under normal (nonstress) conditions, the COMT A allele (Met carriers, higher dopamine) associates with healthier affect and lower afternoon cortisol levels in women. These effects were limited to affective measures and not to physical or environmental quality of life.

Conclusions

These findings help to shed light on the complex nature of COMT and emotion, and suggest that both sex and task condition (stress vs. nonstress) should be considered when examining the relationship between COMT genotype and emotion.

Depression as a risk factor for Alzheimer's disease: Genes, steroids, cytokines and neurogenesis - What do we need to know?

Depression (MDD) is prodromal to, and a component of, Alzheimer's disease (AD): it may also be a trigger for incipient AD. MDD is not a unitary disorder, so there may be particular subtypes of early life MDD that pose independent high risks for later AD, though the identification of these subtypes is problematical. There may either be a common pathological event underlying both MDD and AD, or MDD may sensitize the brain to a second event ('hit') that precipitates AD. MDD may also accelerate brain ageing, including altered DNA methylation, increased cortisol but decreasing DHEA and thus the risk for AD. So far, genes predicting AD (e.g. APOEε4) are not risk factors for MDD, and those implicated in MDD (e.g. SLC6A4) are not risks for AD, so a common genetic predisposition looks unlikely. There is as yet no strong indication that an epigenetic event occurs during some forms of MDD that predisposes to later AD, though the evidence is limited. Glucocorticoids (GCs) are disturbed in some cases of MDD and in AD. GCs have marked degenerative actions on the hippocampus, a site of early β-amyloid deposition, and rare genetic variants of GC-regulating enzymes (e.g. 11β-HSD) predispose to AD. GCs also inhibit hippocampal neurogenesis and plasticity, and thus episodic memory, a core symptom of AD. Disordered GCs in MDD may inhibit neurogenesis, but the contribution of diminished neurogenesis to the onset or progression of AD is still debated. GCs and cytokines also reduce BDNF, implicated in both MDD and AD and hippocampal neurogenesis, reinforcing the notion that those cases of MDD with disordered GCs may be a risk for AD. Cytokines, including IL1β, IL6 and TNFα, are increased in the blood in some cases of MDD. They also reduce hippocampal neurogenesis, and increased cytokines are a known risk for later AD. Inflammatory changes occur in both MDD and AD (e.g. raised CRP, TNFα). Both cytokines and GCs can have pro-inflammatory actions in the brain. Inflammation (e.g. microglial activation) may be a common link, but this has not been systematically investigated. We lack substantial, rigorous and comprehensive follow-up studies to better identify possible subtypes of MDD that may represent a major predictor for later AD. This would enable specific interventions during critical episodes of these subtypes of MDD that should reduce this substantial risk.

In search of HPA axis dysregulation in child and adolescent depression

Dysregulation of the hypothalamic–pituitary–adrenal (HPA) axis in adults with major depressive disorder is among the most consistent and robust biological findings in psychiatry. Given the importance of the adolescent transition to the development and recurrence of depressive phenomena over the lifespan, it is important to have an integrative perspective on research investigating the various components of HPA axis functioning among depressed young people. The present narrative review synthesizes evidence from the following five categories of studies conducted with children and adolescents: (1) those examining the HPA system’s response to the dexamethasone suppression test (DST); (2) those assessing basal HPA axis functioning; (3) those administering corticotropin-releasing hormone (CRH) challenge; (4) those incorporating psychological probes of the HPA axis; and (5) those examining HPA axis functioning in children of depressed mothers. Evidence is generally consistent with models of developmental psychopathology that hypothesize that atypical HPA axis functioning precedes the emergence of clinical levels of depression and that the HPA axis becomes increasingly dysregulated from child to adult manifestations of depression. Multidisciplinary approaches and longitudinal research designs that extend across development are needed to more clearly and usefully elucidate the role of the HPA axis in depression.

Treatment-seeking inpatient cocaine abusers show hypothalamic dysregulation of both basal prolactin and cortisol secretion

Cocaine causes neuroendocrine aberrations in cocaine abusers with pituitary stress hormone secretion providing a window to the stress system in the brain. Substance abusers and control participants were hormonally profiled for 3 weeks. Abusers showed significant basal elevations in prolactin in week 1 with normalization over the 3 weeks. No differences in prolactin secretion were seen with either thyrotropin-releasing hormone stimulation or L-dopa suppression testing. Basal afternoon cortisol secretion was significantly elevated during weeks 1 and 2 comparing abusers to controls. Elevated afternoon cortisol secretion is a sensitive indicator of central stress activation. These results point to the hypothalamus, not the pituitary gland, as being primarily altered in cocaine withdrawal. The data demonstrate that both the dopamine-prolactin and hypothalamic-pituitary-adrenal (HPA) axes are affected during cocaine cessation. As medications are developed to modulate activation of a dysfunctional stress system, future therapeutic studies of substance abuse, withdrawal, craving and relapse should employ more sophisticated tests of hypothalamic pituitary function, especially the HPA axis, as this information may be a guide in the diagnosis and predict clinical responses.

The relevance of the in- versus outpatient status for studies on HPA-axis in depression: spontaneous hypercortisolism is a feature of major depressed inpatients and not of major depression per se

Increased spontaneous activity of the hypothalamic-pituitary-adrenal (HPA)-axis is frequently reported in major depressed inpatients. The aim of the present study was to determine whether there are differences in spontaneous HPA-axis activity between major depressed inpatients and outpatients. Toward this end, the authors measured basal 9:00 a.m. plasma cortisol and the integrated assessment of plasma morning cortisol secretion over 2 (AUC 120) hours in 48 major depressed inpatients, 17 major depressed outpatients and 73 normal volunteers. Major depressed inpatients exhibit significantly higher plasma cortisol values than healthy controls and major depressed outpatients. The cortisol data from the latter are not significantly different from these of the healthy controls. The cortisol differences between in and outpatients were still present after considering the influences of age, sex, body mass index, severity or endogeneity of illness, unipolar/bipolar subclassification, or specific symptoms such as suicidal thoughts, insomnia, psychomotor disorders, psychoticism, weight loss or anxiety. The results indicate that hypercortisolism as measured by basal morning plasma levels is not a feature of major depression per se, but rather of an interaction between the illness and hospitalization.

Benzodiazepine-induced sedation and cortisol suppression. A placebo-controlled comparison of oxazepam and nitrazepam in healthy male volunteers

The sedative and cortisol suppressing properties of oxazepam (45 and 60 mg) and nitrazepam (10 and 15 mg) were examined in eight healthy male subjects. The most clear differences between oxazepam and nitrazepam were those seen with respect to the time course and until maximal effect (Tmax) of the different measurements. Nitrazepam showed maximal sedation after 1 h, maximal benzodiazepine level (RRA), and reaction time prolongation after 2 h, and maximal cortisol suppression after 3 h. Oxazepam showed maximal sedation after 2 h, maximal benzodiazepine levels, reaction time prolongation and cortisol suppression after 3 h. After administration of oxazepam (both doses) a transient return to baseline levels of cortisol was demonstrated. Whereas the degree of sedation correlated significantly within drug groups with the concurrent benzodiazepine levels, the Tmax of sedation was recorded 1 h earlier than the peak blood concentration (RRA) for both nitrazepam and oxazepam. The time course for cortisol suppression for the two compounds differed clearly from the other measurements and was not related to the peak blood concentration.

24-hour cortisol measures in adolescents with major depression: a controlled study

Plasma cortisol levels were determined every 20 min for 24 hr in depressed adolescents (n = 27) meeting research diagnostic criteria (RDC) for major depressive disorder (MDD) and normal controls (n = 32). All subjects were between 12 and 18 years of age, at least Tanner Stage III of sexual development, medically healthy, and medication free at the time of the studies. The results showed that cortisol secretory patterns were very similar between the two groups with the exception that the depressed adolescents showed significantly elevated cortisol levels around sleep onset (a period when cortisol is usually suppressed). Subgroup analyses showed that most of these differences were contributed by the suicidal/inpatient depressed adolescents. The cause of the elevated cortisol during the normally quiescent period warrants further investigation and may be related to other biological disturbances around sleep onset (difficulty initiating sleep, reduced rapid eye movement (REM) latency, and alterations in sleep-stimulated growth hormone secretion).

Cortisol and treatment of depression: predictive value of spontaneous and suppressed cortisol levels and course of spontaneous plasma cortisol

In 72 consecutive depressed hospitalized patients afternoon plasma cortisol was measured in three ways before treatment with antidepressants: 1) Spontaneous (n = 72), 2) 2h after oxazepam suppression (45 mg, n = 28; 60 mg, n = 37) and 3) 16 h after dexamethasone suppression (2 mg, n = 71). In addition, spontaneous cortisol was measured after 3 weeks' treatment (n = 55) and 5 weeks' treatment (n = 36). Both spontaneous and suppressed cortisol levels seemed to have a predictive value in the endogenously depressed patients: complete responders had significantly lower pretreatment cortisol levels compared to poor responders. However, other covarying factors such as distress and age may as well account for the differences in treatment effect. During treatment a significant decrease of spontaneous cortisol was found from about 400 nM in poor responders and 325 nM in complete responders to about 300 nM in all groups. There was a positive correlation between pre- and post-treatment cortisol levels and between pretreatment levels and per cent fall in spontaneous cortisol levels.

Afternoon plasma cortisol in relation to depression. A replication study

In 37 consecutive depressed inpatients afternoon plasma cortisol (1500-1520 h) was measured in 3 ways: 1) spontaneously; 2) 2 h after oral administration of 60 mg oxazepam; and 3) 16 h after oral administration of 2 mg dexamethasone. Both oxazepam and dexamethasone caused a significant suppression of cortisol secretion. Spontaneous and suppressed cortisol levels correlated significantly to stress/distress items on the Hamilton Rating Scale for Depression (sum of items 8, 9, 10 and 12), whereas no correlations to age, or type of depression were found. In an earlier similar study of 35 patients both spontaneous and suppressed cortisol levels correlated significantly with age, type and severity of depression as well as with the stress/distress items. Those patients were older, more depressed (HRSD-17) and had higher stress/distress scores compared with the present sample of 37 patients. The consistent finding of a correlation with the stress/distress items suggest that this factor is important in relation to the hypersecretion of cortisol during depression and this may explain the limited diagnostic power of spontaneous and suppressed cortisol levels.

Plasma dexamethasone and the dexamethasone suppression test. Initial and follow-up tests in depressed patients

Plasma dexamethasone concentrations following oral dexamethasone administration were examined in 78 patients with major depression prior to and during treatment. The test-retest stability of plasma dexamethasone levels within patients was satisfactory with an overall significant positive correlation between tests for each patient. However, significant variability was noted in individual patients. Change in pre-DST cortisol and plasma dexamethasone levels were the two variables, in that order of importance, contributing to change in DST status. In studies examining the clinical utility of serial dexamethasone suppression tests as a guide to recovery from depression, the effect of variability in plasma dexamethasone concentrations should be taken into account.

Nocturnal prolactin and cortisol secretion and recovery from melancholia

Spontaneous prolactin and cortisol patterns were determined at 20 min intervals over 3 hr during the night in eight patients with melancholia, both during illness and after treatment with amitriptyline. Mean plasma prolactin levels were greater after recovery in the seven patients who responded to treatment. Mean cortisol secretion decreased upon recovery from melancholia, and such changes in two patients paralleled normalization of dexamethasone suppression test responses. The influence of assumptions of lack of interaction on the statistical significance of the analysis of variance with repeated measures for prolactin and cortisol values was evaluated.

Afternoon cortisol levels before (spontaneous) and after suppression with dexamethasone or oxazepam in depressed patients

In 35 hospitalized depressed patients afternoon plasma cortisol (15:00-15:20 h) was measured in 3 ways: spontaneous, 2 h after administration of 45 mg oxazepam, and 16 h after administration of 2 mg dexamethasone. Dexamethasone and oxazepam caused a marked suppression of cortisol secretion, the former being the most pronounced. A significant correlation between spontaneous and suppressed cortisol levels was found and a correlation between the suppressed cortisol levels was also demonstrated. Both spontaneous and suppressed cortisol values correlated with measures of type (Newcastle scales) and severity (Hamilton rating scale) of depression, and the highest correlations were obtained with cortisol values after dexamethasone suppression. Analysis of the items of the Hamilton rating scale for depression showed a high correlation with retardation (items 7 + 8) and somatic complaints (items 12 + 13). A high correlation with the items 8 + 9 + 10 + 12, as found in an earlier study, was also found in this study. On the basis of these findings it is concluded that hypersecretion of cortisol measured spontaneously or after suppression is not a true diagnostic measure (within a group of depressed patients), but reflects differences in the intensity of certain psychiatric symptoms constituting the depressive syndrome.