COGNITIVE AND AFFECTIVE DISORDERS IN THE ELDERLY: A NEUROENDOCRINE STUDY

Role of CRF and the hypothalamic-pituitary-adrenal axis in stroke: revisiting temporal considerations and targeting a new generation of therapeutics

Ischaemic neurovascular stroke represents a leading cause of death in the developed world. Preclinical and human epidemiological evidence implicates the corticotropin-releasing factor (CRF) family of neuropeptides as mediators of acute neurovascular injury pathology. Preclinical investigations of the role of CRF, CRF receptors and CRF-dependent activation of the hypothalamic-pituitary-adrenal (HPA) axis have pointed toward a tissue-specific and temporal relationship between activation of these pathways and physiological outcomes. Based on the literature, the major phases of ischaemic stroke aetiology may be separated into an acute phase in which CRF and anti-inflammatory stress signalling are beneficial and a chronic phase in which these contribute to neural degeneration, toxicity and apoptotic signalling. Significant gaps in knowledge remain regarding the pathway, temporality and systemic impact of CRF signalling and stress biology in neurovascular injury progression. Heterogeneity among experimental designs poses a challenge to defining the apparent reciprocal relationship between neurological injury and stress metabolism. Despite these challenges, it is our opinion that the elucidated temporality may be best matched with an antibody against CRF with a half-life of days to weeks as opposed to minutes to hours as with small-molecule CRF receptor antagonists. This state-of-the-art review will take a multipronged approach to explore the expected potential benefit of a CRF antibody by modulating CRF and corticotropin-releasing factor receptor 1 signalling, glucocorticoids and autonomic nervous system activity. Additionally, this review compares the modulation of CRF and HPA axis activity in neuropsychiatric diseases and their counterpart outcomes post-stroke and assess lessons learned from antibody therapies in neurodegenerative diseases.

Risk factors and consequences of depression in later life: Findings from the health in men study (HIMS)

Background

The Health In Men Study (HIMS) has been collecting data on risk factors and health events for the past 25 years in a large community-representative sample of older men. This paper summarises key-findings of the study about depression in later life.

Methods

Narrative review of selected HIMS studies published over the past 15 years describing risk factors associated with prevalent and incident depression in older men, as well as clinical outcomes associated with depression.

Results

Data from HIMS showed that cardiovascular diseases and risk factors are associated with increased risk of depression, but this association is neither specific nor causative. Findings from HIMS are not supportive of the vascular hypothesis of depression in later life. Studies investigating lifestyle have generated risk tables capable of guiding risk reduction strategies. Other potentially modifiable risk factors associated with depression in the HIMS cohort included abnormal allostatic inflammatory response, high plasma homocysteine and low testosterone. The results from HIMS also showed that depression is most likely a prodromal manifestation of dementia rather that a true risk factor, but it increases frailty and mortality. The association between depression and suicide in older men is largely mediated by deteriorating health and increasing frailty.

Conclusion

HIMS has contributed to advance knowledge about risk factors associated with depression, as well as the health consequences of depression in older men. The study is ongoing and the investigators welcome the opportunity to share data with colleagues who are interested in the health of older people.

Diurnal Cortisol Slope Mediates the Association Between Affect and Memory Retrieval in Older Adults With Mild Cognitive Impairment: A Path-Analytical Study

Background

Memory deficits are linked to dysfunctional HPA axis activity and negative affect in older adults. This study evaluated the mediating effect of the diurnal cortisol pattern on the relationship between affect and memory in older people with mild cognitive impairment (MCI).

Methods

This longitudinal study recruited 189 Chinese older adults with MCI from elderly centers in Hong Kong. The participants completed assessments of affect, salivary cortisol, and digit spans at baseline; neurocognitive assessments on verbal fluency, memory retrieval, and digit spans at 6-month follow-up; and instrumental activities of daily living (IADL) at 1-year follow-up. Structural equation modeling examined the direct and indirect effects of negative affect on memory and IADL via diurnal cortisol pattern.

Results

Controlling for covariates, negative affect significantly predicted flattened diurnal cortisol slopes (β = 0.17, p < 0.05) but not memory or IADL (p = 0.23 – 0.91) directly. Diurnal cortisol slopes negatively predicted memory retrieval (β = −0.20, p < 0.05), which in turn positively predicted IADL (β = 0.22, p < 0.01). The indirect effect from negative affect to IADL via cortisol slope and memory retrieval was significant and negative (αβγ = −0.05, 95% bootstrapped CI = −0.248 to −0.001).

Discussion

The present study established certain temporal linkages among affect and cortisol slopes at baseline, memory retrieval at 6 months, and functional decline 1 year later in older adults with MCI. Flattened diurnal cortisol slopes might mediate the detrimental effects of negative affect on memory retrieval and functioning across 1 year.

Investigation of the relationship between salivary cortisol, dehydroepiandrosterone sulfate, anxiety, and depression in patients with hyperemesis gravidarum

BACKGROUND

The aim of this study was to determine the relationship of the salivary levels of dehydroepiandrosterone sulfate (DHEA-S) and cortisol with factors related to depression and anxiety in patients with hyperemesis gravidarum (HG).

METHODS

Forty patients with a diagnosis of HG were selected for the study and matched with 40 control patients according to body mass index, parity, and age. Symptoms of depression and anxiety were investigated using the Beck Depression Inventory and Beck Anxiety Inventory for Adults, respectively. Saliva samples were collected in the morning and at night and subjected to enzyme-linked immunosorbent assay for the determination of DHEA-S and cortisol levels.

RESULTS

We observed a positive correlation between increased levels of depression and anxiety and increased salivary levels of cortisol and DHEA-S in patients with HG.

CONCLUSIONS

Salivary cortisol and DHEA-S levels, as well as mood disorders, should be monitored in patients with HG, although further large, prospective studies are needed to confirm our results.

Serum DHEAS levels are associated with the development of depression

The aim of study was to evaluate the association between serum DHEAS levels and depression with a case-control study together with a meta-analysis. Radioimmunoassay (RIA) was performed to measure the serum DHEAS levels of all participants before and after treatment. Depression Patients were divided into mild depression and severe depression based on Hamilton depression scale (HAMD24) and received 5-hydroxytryptamine (5-HT) and citalopram (20mg/d) for 8 weeks. Case-control studies related to our study theme were enrolled for meta-analysis and Comprehensive Meta-analysis 2.0 (CMA 2.0) was used for statistical analysis. After treatment, DHEAS levels in depression patients were significantly increased, while before and after treatment, DHEAS levels were all lower in depression patients than in controls (all P<0.001); further analysis on age revealed that DHEAS levels were decreased with the rising of age. Meta-analysis results suggested that serum DHEAS levels (ng/mL) were significantly higher in healthy controls compared to depression patients (SMD=0.777, 95%CI=0.156-1.399, P=0.014). In conclusion, our study suggests that serum DHEAS levels are associated with the development of depression and it decreased with the rising of age.

Serum dehydroepiandrosterone (DHEA) and DHEA-sulfate (S) levels in medicated patients with major depressive disorder compared with controls

BACKGROUND

There is accumulating evidence regarding gender differences in clinical symptoms or response to antidepressants in patients with depression. However, less attention has been given to sex differences in the underlying biological mechanisms of depression. The adrenal androgens, dehydroepiandrosterone (DHEA) and its sulfate derivative (DHEA-S), play a critical role in controlling affect, mood, and anxiety. Changes in serum adrenal androgen levels have been reported in conditions pertaining to stress as well as in psychiatric disorders. The objective of the present study was to investigate differences in serum levels of adrenal androgens in male and female patients with major depressive disorder (MDD).

METHODS

Participants included 90 inpatients with MDD at the psychiatric ward of Juntendo University Koshigaya Hospital who were receiving antidepressants. Serum levels of DHEA and DHEA-S were assessed at the time of admission. Matched controls (based on sex and age) included 128 healthy individuals. First, data from male and female MDD patients and controls were compared. Second, correlations between serum hormone levels and scores on the Hamilton Rating Scale for Depression (HAM-D) of patients with MDD were assessed by gender. In addition, effects of various factors on adrenal androgens were analyzed using multiple regression analysis.

RESULTS

Serum DHEA levels were significantly increased in both male and female MDD patients compared with controls. Serum levels of DHEA-S in male patients were significantly decreased compared with male controls, whereas no significant differences were seen in female patients and controls. No significant correlations among adrenal androgens were observed in male patients with MDD, whereas significant positive correlations were found in both male and female controls. No significant correlations were seen between adrenal androgens and HAM-D scores in male or female patients. Multiple regression analysis showed that both hormones were affected by the age at onset of depression.

LIMITATIONS

All subjects in the present study were on antidepressant medications.

CONCLUSIONS

Elevated levels of serum DHEA may be associated with the biological pathophysiology of depression, as DHEA administration has been found to be effective for the treatment of depression. Findings of differential changes in DHEA-S levels in men compared with women may suggest distinct characteristics of these hormones between men and women with depression. However, DHEA/DHEA-S may be a poor indicator for evaluating severity of depression.

[Anxiety and depression in the elderly]

OBJECTIVES

This paper deals with diagnostics and prevalence of depression and anxiety in the elderly, their biological, psychological, and social risk factors, and the effectiveness of psychotherapy and pharmacotherapy.

METHODS

The results are based on an overview of the literature reflecting reviews and meta-analyses.

RESULTS

In the elderly, there is a substantial danger of confounding psychogenic with medical or drug-induced symptoms. Self-assessment scales may be useful for screening, but the results should be confirmed by an expert interview. Based on the available research, we cannot yet be sure whether the prevalence of depression and anxiety in the elderly population is in fact higher, lower, or equal to younger age groups. More women are afflicted with depression or anxiety than men. Pharmacotherapy (preferably antidepressants) and psychotherapy are effective for treating anxiety and depression in the elderly, with medium to high effect sizes. To date it is not possible to provide evidence-based treatment recommendations for the type or the setting of psychotherapy.

DISCUSSION

More research on this topic is needed.

Depression and coronary heart disease

There are exciting findings in the field of depression and coronary heart disease. Whether diagnosed or simply self-reported, depression continues to mark very high risk for a recurrent acute coronary syndrome or for death in patients with coronary heart disease. Many intriguing mechanisms have been posited to be implicated in the association between depression and heart disease, and randomized controlled trials of depression treatment are beginning to delineate the types of depression management strategies that may benefit the many coronary heart disease patients with depression.

Neuroactive steroids in affective disorders: target for novel antidepressant or anxiolytic drugs?

In the past decades considerable evidence has emerged that so-called neuroactive steroids do not only act as transcriptional factors in the regulation of gene expression but may also alter neuronal excitability through interactions with specific neurotransmitter receptors such as the GABA(A) receptor. In particular, 3α-reduced neuroactive steroids such as allopregnanolone or allotetrahydrodeoxycorticosterone have been shown to act as positive allosteric modulators of the GABA(A) receptor and to play an important role in the pathophysiology of depression and anxiety. During depression, the concentrations of 3α,5α-tetrahydroprogesterone and 3α,5β-tetrahydroprogesterone are decreased, while the levels of 3β,5α-tetrahydroprogesterone, a stereoisomer of 3α,5α-tetrahydroprogesterone, which may act as an antagonist for GABAergic steroids, are increased. Antidepressant drugs such as selective serotonin reuptake inhibitors (SSRIs) or mirtazapine apparently have an impact on key enzymes of neurosteroidogenesis and have been shown to normalize the disequilibrium of neuroactive steroids in depression by increasing 3α-reduced pregnane steroids and decreasing 3β,5α-tetrahydroprogesterone. Moreover, 3α-reduced neuroactive steroids have been demonstrated to possess antidepressant- and anxiolytic-like effects both in animal and human studies for themselves. In addition, the translacator protein (18 kDa) (TSPO), previously called peripheral benzodiazepine receptor, is the key element of the mitochondrial import machinery supplying the substrate cholesterol to the first steroidogenic enzyme (P450scc), which transforms cholesterol into pregnenolone, the precursor of all neurosteroids. TSPO ligands increase neurosteroidogenesis and are a target of novel anxiolytic drugs producing anxiolytic effects without causing the side effects normally associated with conventional benzodiazepines such as sedation or tolerance. This article is part of a Special Issue entitled: Neuroactive Steroids: Focus on Human Brain.

Association between altered systemic inflammatory interleukin-1beta and natural killer cell activity and subsequently agitation in patients with Alzheimer disease

OBJECTIVE

Alzheimer's disease (AD) is a neurodegenerative disorder that is the most common cause of dementia in the elderly and is frequently accompanied by emotional disorder, including agitation. Although evidence of neuroendocrine immune and inflammatory functions during emotional changes has been accumulated, the pathogenic mechanisms in the development of agitation accompanied by AD remain to be elucidated.

METHODS

To clarify the involvement of neuroendocrine and immune and inflammatory systems in agitation in AD, we examined agitation levels, circadian rhythms of behavior, cortisol, interleukin-1beta (IL-1beta), and natural killer cell activity (NKCA) in controls without dementia and 16 AD patients who were recognized to be easily agitated in their nursing homes. These behavioral and blood indicators were assessed according to the progress of the stage of agitation in 16 AD patients (stable, pre-agitation, and agitation stages).

RESULTS

Elevations in night behavior and blood cortisol, IL-1beta and an reduced blood NKCA level in the evening were observed not only in the agitation stage, but also when stable in AD patients as compared to the control. Increased IL-1beta and decreased NKCA occurred in both the morning and evening in pre-agitation and agitation stages in AD.

CONCLUSIONS

The increased IL-1beta and decreased NKCA with the progress of agitation in AD suggest that inflammation produces agitation and aggravates AD.

Confronting challenges in intervention research with ethnically diverse older adults: the USC Well Elderly II Trial

BACKGROUND

Community-dwelling older adults are at risk for declines in physical health, cognition, and psychosocial well-being. However, their enactment of active and health-promoting lifestyles can reduce such declines.

PURPOSE

The purpose of this article is to describe the USC Well Elderly II study, a randomized clinical trial designed to test the effectiveness of a healthy lifestyle program for elders, and document how various methodological challenges were addressed during the course of the trial.

METHODS

In the study, 460 ethnically diverse elders recruited from a variety of sites in the urban Los Angeles area were enrolled in a randomized experiment involving a crossover design component. Within either the first or second 6-month phase of their study involvement, each elder received a lifestyle intervention designed to improve a variety of aging outcomes. At 4-5 time points over an 18-24 month interval, the research participants were assessed on measures of healthy activity, coping, social support, perceived control, stress-related biomarkers, perceived physical health, psychosocial well-being, and cognitive functioning to test the effectiveness of the intervention and document the process mechanisms responsible for its effects.

RESULTS

The study protocol was successfully implemented, including the enrollment of study sites, the recruitment of 460 older adults, administration of the intervention, adherence to the plan for assessment, and establishment of a large computerized data base.

LIMITATIONS

Methodological challenges were encountered in the areas of site recruitment, participant recruitment, testing, and intervention delivery.

CONCLUSIONS

The completion of clinical trials involving elders from numerous local sites requires careful oversight and anticipation of threats to the study design that stem from: (a) social situations that are particular to specific study sites; and (b) physical, functional, and social challenges pertaining to the elder population.

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.

Positive correlation between anxiety severity and plasma levels of dehydroepiandrosterone sulfate in medication-free patients experiencing a major episode of depression

Although numerous studies have identified a correlation between dehydroepiandrosterone sulfate (DHEAS) levels and anxiety or depression, those findings remain controversial. The purpose of the present study was to determine whether a correlation exists between depression severity and anxiety severity and serum DHEAS concentrations in medication-free patients experiencing a major depressive episode. Twenty-eight medication-free major depressive outpatients (Hamilton Rating Scale for Depression 17 [HAM-D 17] score >or=17) were enrolled consecutively. Plasma DHEAS levels of all subjects were measured. Blood from subjects was drawn at 0900-1100 h Depression severity was assessed with the HAM-D 17 and the Hospital Anxiety and Depression Scale (HADS) depression subscale. Anxiety was assessed using the HADS anxiety subscale. Serum concentrations of DHEAS were measured immediately following the HAM-D 17 and HADS assessments. A significant, positive correlation was identified between HADS anxiety subscale total score and morning serum DHEAS concentration (P = 0.013) after controlling for age, gender and body mass index (BMI). No statistically significant correlations were found between depression ratings and morning serum DHEAS concentrations. This preliminary study provides pilot data indicating that morning serum DHEAS concentrations were positively correlated with HADS anxiety subscale score (anxiety severity) after controlling for age, gender and BMI in medication-free outpatients experiencing a major depressive episode. It is not known if morning serum DHEAS levels would show similar or dissimilar changes in non-depressed subjects. The present result needs subsequent replication.

Clinical correlates of DHEA associated with post-traumatic stress disorder

OBJECTIVE

Increased plasma dehydroepiandrosterone (DHEA) and dehydroepiandrosterone-sulfate (DHEAS) have been demonstrated in post-traumatic stress disorder (PTSD), but the documented beneficial effects of these steroids in enhancing mood and cognition, as well as neuroprotection, suggest their presence in PTSD may be associated with defensive rather than maladaptive effects.

METHOD

We, therefore, examined plasma DHEA, DHEAS, cortisol, and the DHEA/cortisol ratio in 40 male veterans with or without PTSD, and determined their relationships to PTSD symptom severity and symptom improvement.

RESULTS

The PTSD group showed significantly higher plasma DHEA and non-significantly higher DHEAS levels as well as a significantly lower cortisol/DHEA ratio, controlling for age. Regression analyses demonstrated that DHEA and DHEAS levels could be predicted by symptom improvement and coping, whereas the cortisol/DHEA ratio was predicted by severity of childhood trauma and current symptom severity.

CONCLUSION

That greater symptom improvement was related to DHEA levels may suggest for a role for these hormones in modulating recovery from PTSD.

Difference in pre- and post-treatment plasma DHEA levels were significantly and positively correlated with difference in pre- and post-treatment Hamilton depression scores following successful therapy for major depression

OBJECTIVE

Clinical studies of endogenous concentrations of dehydroepiandrosterone (DHEA) and its relation to depression are limited. This study examined whether pre- and post-treatment changes in plasma DHEA levels are correlated with pre- and post-treatment differences in Hamilton depression scores following successful antidepressant therapy for major depression with venlafaxine XR.

METHOD

Thirty-four medication-free major depressive outpatients (Hamilton Rating Scale for Depression 17, HAM-D 17 score > or = 17) were treated with antidepressants. At baseline, plasma DHEA levels of all subjects were measured but only those who remitted (HAM-D 17 score < or = 7) before the end of this study had their plasma DHEA levels measured at remission-onset. Blood from subjects was drawn at 0900-1100 h. Depression severity was assessed with the HAM-D 17 scale at baseline, and on day 7, 14, 28, 56 and 84. Subjects were administered at minimum 75 mg/day venlafaxine XR until remission onset.

RESULTS

Fifteen patients remitted before the end of this study. Plasma DHEA levels decreased from baseline to remission was significant (P=0.017). After controlling for age and gender, pre- and post-treatment difference in Hamilton depression scores and the pre- and post-treatment difference in DHEA concentrations were significantly correlated (P=0.044).

CONCLUSION

This preliminary study provides the first clinical evidence identifying that difference in pre- and post-treatment plasma DHEA levels were significantly and positively correlated with difference in pre- and post-treatment Hamilton depression scores following successful therapy with venlafaxine XR for major depression in remitters; but non-remitters were not examined. It is not known if DHEA levels would show similar or dissimilar changes in non-remitters.

Dhea supplementation and cognition in postmenopausal women

Previous work has suggested that DHEA supplementation may have adverse cognitive effects in elderly women. This article analyzed 24-h measurements of DHEA, DHEAS, and cortisol to determine if cognitive decrease with treatment is mediated by DHEA's impact on endogenous cortisol. It was found that DHEA administration increased cortisol at several hours during the day. In the treatment group, cortisol was positively associated with cognition at study completion. An increase in negative associations between DHEA(S) levels and cognition was found at completion. Increased cortisol does not explain the cognitive deficits associated with DHEA, suggesting a direct negative effect of exogenous DHEA on cognition.

Salivary cortisol and memory function in human aging

OBJECTIVE

To examine the association of salivary cortisol with cognitive changes in a 3 year longitudinal study. Previous studies have suggested that elevated glucocorticoid concentrations alter hippocampal neuronal morphology, inhibit neurogenesis, and impair cognition.

METHODS

Salivary cortisol samples were collected at home by 79 cognitively intact older persons (mean age 78+/-7 years) at 08:00, 15:00 and 23:00h, and collections were repeated annually for 3 years. Cognitive function was also assessed annually.

RESULTS

The mean cortisol level of samples taken at three times of day and the cortisol concentration at 23:00h were significantly associated with poorer performance on tasks of declarative memory and executive function. Of 46 subjects who completed the entire 3 year study, higher initial cortisol concentration at 23:00h predicted a decline in performance of delayed paragraph recall.

CONCLUSION

These results partially confirm previous findings that high cortisol is associated with impaired declarative memory function in non-demented older persons. In addition, our data show that high salivary cortisol concentrations predict a decline in memory function over the next 3 years.