Influence of mirtazapine on salivary cortisol in depressed patients

Cortisol as a Biomarker of Mental Disorder Severity

Cortisol—the most important steroid hormone with a significant effect on body metabolism—strongly affects peripheral tissues and the central nervous system. Fluctuations in cortisol secretion often accompany psychiatric disorders, and normalization of its levels correlates with improvement in the patient’s health. This indicates that cortisol may be useful as a biological marker that can help determine the likelihood of mental illness, its impending onset, and the severity of symptoms, which is especially important in the face of the increasing prevalence of mental disorders, including those associated with social isolation and anxiety during the COVID-19 pandemic. This publication reviews recent reports on cortisol levels in healthy participants and shows the current state of knowledge on changes in the levels of this hormone in people at risk for depression, bipolar disorder, and psychosis. It shows how people with psychiatric disorders react to stressful situations and how the applied therapies affect cortisol secretion. The influence of antidepressants and antipsychotics on cortisol levels in healthy people and those with mental disorders is also described. Finally, it reviews publications on the patterns of cortisol secretion in patients in remission.

Effects of antidepressant drug therapy with or without physical exercise on inflammatory biomarkers in major depressive disorder: a systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

To conduct a systematic review and meta-analysis of the effects of antidepressant drug therapy (with or without physical exercise) on peripheral inflammatory markers in patients with major depressive disorder (MDD).

METHODS

MEDLINE, PyscINFO, Embase, and Google Scholar databases were searched until May 2020. Randomized trials that measured at least one inflammatory biomarker and included adult outpatients with MDD under antidepressant drug therapy (any drug) with or without physical exercise (any modality) were eligible. Results were summarized using the standardized mean difference (SMD) with 95% confidence intervals (95% CI) under a random-effects model. The Cochrane risk of bias tool (2010) was used to evaluate the risk of bias in the included trials.

RESULTS

Sixty-three trials were identified, encompassing data from 3482 patients, and 20 investigated biomarkers. Trials had biases across multiple domains, rising concerns primarily to selection bias/performance bias/detection bias/attrition bias. SMDs between pre- and post-results indicated a significant reduction in the levels of IL-2 (SMD, - 0.25; 95% CI, - 0.41 to - 0.09, P = 0.002), IL-6 (SMD, - 0.19; 95% CI, - 0.35 to - 0.025, P = 0.024), IL-10 (SMD, - 0.32; 95% CI, - 0.57 to - 0.07, P = 0.011), and serum cortisol (SMD, - 0.35; 95% CI, - 0.58 to - 0.12, P = 0.002). Evidence supporting the influence of physical exercise combined with antidepressant drugs on peripheral inflammatory markers in MDD is sparse and heterogeneous.

CONCLUSION

There is some evidence that antidepressant drug therapy is associated with an overall positive reduction in inflammatory markers, but the evidence is heterogeneous. Further research linking how inflammatory biomarkers modulate physiology related to antidepressant response is required.

TRIAL REGISTRATION

CRD42020220735.

An initial exploration of hair cortisol responses to antidepressants in unmedicated patients with depression

OBJECTIVE

Major depressive disorder is associated with abnormal functioning of the hypothalamic-pituitary-adrenal (HPA) axis. Studies using hair cortisol to measure the effect of antidepressants on the HPA axis are lacking. The aim of this study was to explore the long-term effects of antidepressants on hair cortisol concentration (HCC).

METHODS

Participants were 42 patients and 36 healthy individuals. The patients took antidepressants for 4 weeks. Patient HCC was measured pre-treatment and post-treatment. The HCC of healthy controls was also measured.

RESULTS

Patient post-treatment HCC (mean ± standard deviation: 34.40 ± 32.57 pmol/mg) was significantly higher than patient pre-treatment HCC (17.42 ± 12.40 pmol/mg) and healthy control HCC (10.22 ± 7.99 pmol/mg). No significant correlation was found between Hamilton Depression Rating Scale scores and HCC at pre-treatment or post-treatment.

CONCLUSIONS

Hair cortisol concentration analysis could be used to monitor the dynamics of the effects of antidepressants on the HPA axis.

In Individuals Following Aneurysmal Subarachnoid Haemorrhage, Hair Cortisol Concentrations Are Higher and More Strongly Associated with Psychological Functioning and Sleep Complaints than in Healthy Controls

BACKGROUND

Following an aneurysmal subarachnoid haemorrhage (aSAH), many patients report persistent deficits in psychological functioning, characterised by high levels of stress and symptoms of depression, low life satisfaction, along with poor sleep. Such deficits have been associated with altered saliva and serum cortisol levels due to a dysregulation of hypothalamic-pituitary-adrenal axis activity (HPA-AA). However, hair cortisol concentrations (HCCs) have not been assessed in this population, although this method allows a long-term insight into cortisol values. Therefore, the objective of this study was to compare HCCs in aSAH patients and healthy controls and to examine how HCCs are associated with perceived stress, psychological functioning, and sleep complaints.

METHODS

In this cross-sectional study, data on depressive symptoms, hypochondriacal beliefs, life satisfaction, and sleep complaints were gathered in 15 aSAH patients and 17 healthy controls. HCCs of the previous 3 months were assessed.

RESULTS

aSAH patients had significantly higher HCCs than healthy controls. In aSAH patients, higher HCCs were significantly associated with increased depressive symptoms, hypochondriacal beliefs, lower life satisfaction, and increased sleep complaints. Such significant associations were not found in healthy controls.

CONCLUSIONS

Our findings indicate that a dysregulation of HPA-AA is associated with some of the long-term impairments in psychological functioning and sleep in aSAH survivors. While the direction of association remained unclear, a dysregulated HPA-AA may be causally linked with the maintenance of poor psychological functioning and poor sleep. The overall findings should be considered in the planning of long-term treatment aimed at improving psychological functioning and sleep in aSAH patients.

Hypothalamic-pituitary-adrenocortical axis: neuropsychiatric aspects

Evidence of aberrant hypothalamic-pituitary-adrenocortical (HPA) activity in many psychiatric disorders, although not universal, has sparked long-standing interest in HPA hormones as biomarkers of disease or treatment response. HPA activity may be chronically elevated in melancholic depression, panic disorder, obsessive-compulsive disorder, and schizophrenia. The HPA axis may be more reactive to stress in social anxiety disorder and autism spectrum disorders. In contrast, HPA activity is more likely to be low in PTSD and atypical depression. Antidepressants are widely considered to inhibit HPA activity, although inhibition is not unanimously reported in the literature. There is evidence, also uneven, that the mood stabilizers lithium and carbamazepine have the potential to augment HPA measures, while benzodiazepines, atypical antipsychotics, and to some extent, typical antipsychotics have the potential to inhibit HPA activity. Currently, the most reliable use of HPA measures in most disorders is to predict the likelihood of relapse, although changes in HPA activity have also been proposed to play a role in the clinical benefits of psychiatric treatments. Greater attention to patient heterogeneity and more consistent approaches to assessing treatment effects on HPA function may solidify the value of HPA measures in predicting treatment response or developing novel strategies to manage psychiatric disease.

Glucocorticoids as predictors of treatment response in depression

INTRODUCTION

Glucocorticoids and the stress hormone system have been implicated in the pathophysiology of depression and in the mechanism of action of antidepressant response. Many studies have investigated this system in an effort to predict response to antidepressant treatment. The purpose of this review is to evaluate the evidence for using glucocorticoid-related measures for personalized treatment of depression.

METHODS

We conducted a MEDLINE search from 1966 through 2010 and examined English-language studies reporting on the use of endocrine challenge tests and genetic polymorphisms in genes regulating the stress hormone system as predictors of antidepressant response.

RESULTS

While measures of glucocorticoid levels using endocrine tests, as well polymorphisms in genes regulating the stress hormone system, show associations with response to antidepressant treatment, these measures will need to be combined with other variables, including clinical information and other biological measures, to realize the goal of highly predictive and clinically relevant biomarkers.

DISCUSSION

The glucocorticoid system is potentially of great use in predicting antidepressant response. New combinations of biomarkers including these measures should be tested to develop clinically relevant predictors.

Antidepressant-like effects of rosiglitazone, a PPARγ agonist, in the rat forced swim and mouse tail suspension tests

Several studies have evaluated thiazolidinedione therapy as medical treatments for some central nervous system disorders, such as cognitive deficits associated with neurodegenerative disorders. However, there is limited data to support a direct role for peroxisome proliferator-activated receptor-γ agonists in depression. Therefore, the aim of this study was to investigate antidepressant-like activity of rosiglitazone using the mouse tail suspension test and the rat forced swimming test, two models sensitive to the effects of antidepressants. In the tail suspension test, 5 days of treatment with rosiglitazone (8.5 or 17 mg/kg, orally) reduced immobility time. In the forced swimming test, rosiglitazone (6 or 12 mg/kg, orally) treatment decreased immobility time and increased climbing. These effects were not accompanied by any alteration in locomotor activity in the open field test. Rosiglitazone treatment (6 or 12 mg/kg, orally) significantly reduced plasma corticosterone levels in rats. GW9662 significantly inhibited the rosiglitazone-induced reduction in the duration of immobility. In summary, this study suggests that rosiglitazone possesses a specific antidepressant-like activity in behavioral models and that this effect may be mediated by reduction of plasma corticosterone level.

Mirtazapine does not influence tetrahydrodeoxycorticosterone levels in depressed patients

BACKGROUND

Among the neuroactive steroids, 3alpha,5alpha-tetrahydrodeoxycorticosterone (3alpha,5alpha-THDOC) is at least in part produced in the adrenal gland and is therefore under the control of the hypothalamic-pituitary-adrenocortical (HPA) system. The antidepressant mirtazapine has been shown to attenuate HPA axis activity and to increase the concentrations of 3alpha-reduced metabolites of progesterone in depressed patients. In the present study, the impact of mirtazapine on 3alpha,5alpha-THDOC levels was investigated in relation to clinical response in depressed patients.

METHOD

A total of 23 drug-free inpatients suffering from a major depressive episode (DSM-IV criteria) underwent 5-week treatment with mirtazapine (45 mg/day). Plasma samples were taken weekly at 08:00 h and were quantified for 3alpha,5alpha-THDOC levels.

RESULTS

3alpha,5alpha-THDOC levels were not correlated with demographic and clinical parameters such as age and severity of depression. Moreover, 5-week treatment with mirtazapine did not influence the 3alpha,5alpha-THDOC in the depressed patients, neither in responders nor in non-responders.

CONCLUSION

Putative increasing effects of mirtazapine on 3alpha-reduced neuroactive steroids such as 3alpha,5alpha-THDOC which may be mediated via an impact on the neurosteroidogenic enzyme 3alpha-hydroxysteroid dehydrogenase seem to be counterbalanced by the mirtazapine-induced inhibition of ACTH secretion which directly influences the 3alpha,5alpha-THDOC release of the adrenal cortex.

Effects of mirtazapine on dehydroepiandrosterone-sulfate and cortisol plasma concentrations in depressed patients

BACKGROUND

Among the neuroactive steroids, dehydroepiandrosterone sulfate (DHEA-S) is at least in part produced in the adrenal gland and is therefore under the control of the hypothalamic-pituitary-adrenocortical (HPA)-system. In the present study, the impact of mirtazapine on DHEA-S and cortisol (COR) levels was investigated in relation to clinical response in depressed patients.

METHODS

A total of 23 inpatients suffering from a major depressive episode (DSM-IV criteria) underwent 5-week treatment with mirtazapine (45 mg/day). Plasma samples were taken weekly at 0800 h and quantified for COR and DHEA-S levels.

RESULTS

Mirtazapine significantly reduced both COR and DHEA-S concentrations, but had no impact on the COR/DHEA-S ratio. The percentage decrease of DHEA-S, but not that of COR was significantly and positively correlated with the percentage reduction in the sum score of the Hamilton Depression Rating Scale at week 5, suggesting a relationship between DHEA-S reduction and clinical efficacy of mirtazapine. There was a significant positive correlation between the decline in COR and DHEA-S levels.

CONCLUSIONS

Apparently, the decrease in COR and DHEA-S concentrations conjointly reflects an attenuating impact of mirtazapine on HPA axis activity, thereby decreasing the adrenal secretion of COR and DHEA-S.

HPA-axis regulation at in-patient admission is associated with antidepressant therapy outcome in male but not in female depressed patients

A concatenation of data implicates a hyperactivity of the hypothalamus pituitary adrenal (HPA)-axis in the pathogenesis of depression and its normalization as a necessary predecessor of clinical response to antidepressant drugs. In addition, regulation of the HPA-axis has been shown to be dependent on sex hormones. We therefore investigated gender differences in HPA-axis regulation in depression and its normalization during remission of clinical symptoms. We used the combined dexamethasone suppression/CRH stimulation (Dex-CRH) test to evaluate the degree of HPA-axis dysregulation in 194 in-patients with unipolar depression from the Munich Antidepressant Response Signature (MARS) study at both admission and discharge. The Hamilton Depression (HAM-D) Rating Scale was used to monitor clinical response to antidepressant treatment. For both genders, we observed a normalization of HPA-axis dysregulation in remitters but not in non-remitters, both after 5 weeks of treatment and at discharge. The pattern of HPA-axis normalization with remission of depressive symptoms, however, showed gender-specific differences. In male patients, remission after 5 weeks of in-patient treatment was associated with a significantly higher cortisol response in the Dex-CRH test at admission. In female patients, 5-week remitters and non-remitters had a comparable cortisol response at admission. Cortisol response at admission was not correlated with gonadal steroid levels at this time point and the results were similar for pre-menopausal women vs. post-menopausal women. Gender-associated biological characteristics, likely independent of circulating gonadal steroids, thus seem to influence HPA-axis regulation in depression. In male patients, a single measure of HPA-axis dysregulation at admission may serve as a predictor of response to antidepressant treatment in addition to the previously reported repeated measure of the Dex-CRH test.

Neuroendocrinological mechanisms of actions of antidepressant drugs

Noradrenaline or serotonin (5-HT) reuptake-inhibiting antidepressants such as reboxetine or citalopram acutely stimulate cortisol and adrenocorticotrophic hormone (ACTH) secretion in healthy volunteers, whereas mirtazapine acutely inhibits the ACTH and cortisol release, probably due to its antagonism at central 5-HT(2) and/or H(1) receptors. These differential effects of antidepressants on cortisol and ACTH secretion in healthy subjects after single administration are also reflected by their different time course in the down-regulation of hypothalamic-pituitary-adrenocortical (HPA) axis hyperactivity in depressed patients as assessed by serial dexamethasone (DEX)/corticotrophin-releasing hormone (CRH) tests: Reuptake-inhibiting antidepressants such as reboxetine gradually normalise HPA axis hyperactivity in depressed patients during several weeks of treatment via up-regulation of mineralocorticoid and glucocorticoid receptor function and by step-by-step restoration of the disturbed feedback control. By contrast, mirtazapine markedly reduces HPA axis activity in depressed patients within 1 week, but there is a partial re-enhancement of HPA hormone secretion after several weeks of therapy. In all studies performed to date, the short-term effects of daily treatment with antidepressants on the DEX/CRH test results are comparable in responders and nonresponders. Moreover, a reduction in HPA axis activity is not necessarily followed by a favourable clinical response and some depressed patients keep on showing nonsuppression in the DEX/CRH test despite clinical improvement. Therefore, the importance of HPA axis dysregulation for the short-term efficacy of antidepressants continues to be a matter of debate. However, there are convincing data suggesting that persisting nonsuppression in the DEX/CRH test despite clinical remission predicts an enhanced risk for relapse of depressive symptomatology with respect to the medium- and long-term outcome.

Mirtazapine inhibits salivary cortisol concentrations in anorexia nervosa

The antidepressant mirtazapine has been demonstrated to acutely inhibit cortisol concentrations in healthy subjects and depressed patients. Since both depressed and anorectic patients are characterized by hyperactivity of the hypothalamo-pituitary-adrenocortical (HPA) system, the clinical usefulness and the endocrinological effects of mirtazapine were investigated in anorexia nervosa (AN). Five female patients suffering from AN restricting subtype (DSM-IV criteria) were admitted to a closed ward and treated with mirtazapine for three weeks receiving 15 mg mirtazapine on day 0; 30 mg mirtazapine on day 1; and 45 mg mirtazapine per day from day 2 up to the end of the study (day 21). Besides weekly determination of clinical parameters (Body Mass Index [BMI], Hamilton Depression Rating Scale [21-HAMD]), salivary cortisol concentrations were measured before treatment (day - 1), at the beginning of treatment (day 0), after 1 week (day 7), and after 3 weeks (day 21) of treatment with mirtazapine. Saliva samples were collected hourly from 0800 up to 1,400 h. Repeated-measures ANOVA revealed a significant inhibition of salivary cortisol levels during 3-week treatment with mirtazapine (p<0.05) which became obvious already after the first mirtazapine administration (day 0). Moreover, a trend for an increase in BMI was seen (p=0.063), whereas no significant changes in 21-HAMD sum scores could be demonstrated. Double-blind, placebo-controlled studies are needed to clarify the question whether the observed changes in BMI are related to the mirtazapine-induced attenuation of HPA axis activity or whether they are due to monitoring of food intake and purgative behaviour on the closed ward.

Time course of hypothalamic-pituitary-adrenocortical axis activity during treatment with reboxetine and mirtazapine in depressed patients

RATIONALE

In healthy subjects, cortisol and ACTH secretion are acutely stimulated by reboxetine and inhibited by mirtazapine. However, it was not investigated so far whether reboxetine and mirtazapine may also differ in their impact on hypothalamic-pituitary-adrenocortical (HPA) axis activity in depressed patients and whether these effects are related to clinical outcome.

OBJECTIVES

In the present study, we investigated the impact of 5-week treatment with reboxetine or mirtazapine on the combined dexamethasone suppression/corticotropin releasing hormone (DEX/CRH) test results in depressed patients.

METHODS

Forty drug-free patients suffering from a major depressive episode (Diagnostic and Statistical Manual of Mental Disorders-IV criteria) were treated with either reboxetine (8 mg/day; n=20) or mirtazapine (45 mg/day; n=20) for 5 weeks. Before, after 1 and 5 weeks of therapy, the DEX/CRH test was performed and cortisol and ACTH concentrations were measured.

RESULTS

During reboxetine treatment, a gradual and significant reduction in HPA axis activity as measured by the DEX/CRH test was seen, which was most pronounced after 5 weeks of treatment. In contrast, mirtazapine significantly reduced the cortisol and ACTH concentrations during the DEX/CRH test within 1 week. However, after 5 weeks of mirtazapine treatment, the cortisol and ACTH responses to the DEX/CRH test partially increased again both in responders and nonresponders.

CONCLUSIONS

This is the first study demonstrating differential effects of various antidepressants on the time course of serial DEX/CRH test results in depressed patients.

Specificity of autobiographical memories and basal cortisol levels in patients with major depression

This study investigated whether over-general retrieval of autobiographical memories in depression is related to increased basal cortisol levels. Forty-seven individuals with a current diagnosis of major depression were given the autobiographical memory test, in which they were asked to produce specific autobiographical memories following positive, negative and neutral cue words. Salivary cortisol samples were taken at fixed time intervals during testing in the afternoon. Basal cortisol levels did not appear to be markedly elevated and were not significantly correlated with autobiographical memory performance. There were, however, strong negative correlations between memory specificity and decreases of cortisol levels over time of testing. Findings suggest that while specificity of autobiographical memory may be sensitive to cortisol changes, the occurrence of over-general memory in depression is not necessarily due to increased cortisol levels.