Allostasis, allostatic load, and the aging nervous system: role of excitatory amino acids and excitotoxicity

Allostatic interoceptive overload across psychiatric and neurological conditions

Emerging theories emphasize the crucial role of allostasis (anticipatory and adaptive regulation of the body's biological processes) and interoception (integration, anticipation, and regulation of internal bodily states) in adjusting physiological responses to environmental and bodily demands. This review explores the disruptions in integrated allostatic interoceptive mechanisms in psychiatric and neurological disorders, including anxiety, depression, Alzheimer's disease, and frontotemporal dementia. We assess the biological mechanisms associated with allostatic interoception, including whole-body cascades, brain structure and function of the allostatic interoceptive network, heart-brain interactions, respiratory-brain interactions, the gut-brain-microbiota axis, peripheral biological processes (inflammatory, immune), and epigenetic pathways. These processes span psychiatric and neurological conditions and call for developing dimensional and trans-nosological frameworks. We synthesize new pathways to understand how allostatic interoceptive processes modulate interactions between environmental demands and biological functions in brain disorders. We discuss current limitations of the framework and future transdisciplinary developments. This review opens a new research agenda for understanding how allostatic interoception involves brain predictive coding in psychiatry and neurology, allowing for better clinical application and the development of new therapeutic interventions.

A predictive coding framework of allostatic-interoceptive overload in frontotemporal dementia

Recent allostatic-interoceptive explanations using predictive coding models propose that efficient regulation of the body's internal milieu is necessary to correctly anticipate environmental needs. We review this framework applied to understanding behavioral variant frontotemporal dementia (bvFTD) considering both allostatic overload and interoceptive deficits. First, we show how this framework could explain divergent deficits in bvFTD (cognitive impairments, behavioral maladjustment, brain atrophy, fronto-insular-temporal network atypicality, aberrant interoceptive electrophysiological activity, and autonomic disbalance). We develop a set of theory-driven predictions based on levels of allostatic interoception associated with bvFTD phenomenology and related physiopathological mechanisms. This approach may help further understand the disparate behavioral and physiopathological dysregulations of bvFTD, suggesting targeted interventions and strengthening clinical models of neurological and psychiatric disorders.

Allostatic-Interoceptive Overload in Frontotemporal Dementia

BACKGROUND

The predictive coding theory of allostatic-interoceptive load states that brain networks mediating autonomic regulation and interoceptive-exteroceptive balance regulate the internal milieu to anticipate future needs and environmental demands. These functions seem to be distinctly compromised in behavioral variant frontotemporal dementia (bvFTD), including alterations of the allostatic-interoceptive network (AIN). Here, we hypothesize that bvFTD is typified by an allostatic-interoceptive overload.

METHODS

We assessed resting-state heartbeat evoked potential (rsHEP) modulation as well as its behavioral and multimodal neuroimaging correlates in patients with bvFTD relative to healthy control subjects and patients with Alzheimer's disease (N = 94). We measured 1) resting-state electroencephalography (to assess the rsHEP, prompted by visceral inputs and modulated by internal body sensing), 2) associations between rsHEP and its neural generators (source location), 3) cognitive disturbances (cognitive state, executive functions, facial emotion recognition), 4) brain atrophy, and 5) resting-state functional magnetic resonance imaging functional connectivity (AIN vs. control networks).

RESULTS

Relative to healthy control subjects and patients with Alzheimer's disease, patients with bvFTD presented more negative rsHEP amplitudes with sources in critical hubs of the AIN (insula, amygdala, somatosensory cortex, hippocampus, anterior cingulate cortex). This exacerbated rsHEP modulation selectively predicted the patients' cognitive profile (including cognitive decline, executive dysfunction, and emotional impairments). In addition, increased rsHEP modulation in bvFTD was associated with decreased brain volume and connectivity of the AIN. Machine learning results confirmed AIN specificity in predicting the bvFTD group.

CONCLUSIONS

Altogether, these results suggest that bvFTD may be characterized by an allostatic-interoceptive overload manifested in ongoing electrophysiological markers, brain atrophy, functional networks, and cognition.

Association of social isolation, loneliness and genetic risk with incidence of dementia: UK Biobank Cohort Study

BACKGROUND

Social isolation and loneliness have been associated with increased risk of dementia, but it is not known whether this risk is modified or confounded by genetic risk of dementia.

METHODS

We used the prospective UK Biobank study with 155 070 participants (mean age 64.1 years), including self-reported social isolation and loneliness. Genetic risk was indicated using the polygenic risk score for Alzheimer's disease and the incident dementia ascertained using electronic health records.

RESULTS

Overall, 8.6% of participants reported that they were socially isolated and 5.5% were lonely. During a mean follow-up of 8.8 years (1.36 million person years), 1444 (0.9% of the total sample) were diagnosed with dementia. Social isolation, but not loneliness, was associated with increased risk of dementia (HR 1.62, 95% CI 1.38 to 1.90). There were no interaction effects between genetic risk and social isolation or between genetic risk and loneliness predicting incident dementia. Of the participants who were socially isolated and had high genetic risk, 4.4% (95% CI 3.4% to 5.5%) were estimated to developed dementia compared with 2.9% (95% CI 2.6% to 3.2%) of those who were not socially isolated but had high genetic risk. Comparable differences were also in those with intermediate and low genetic risk levels.

CONCLUSIONS

Socially isolated individuals are at increased risk of dementia at all levels of genetic risk.

Burden and Heart Rate Variability in Bipolar Disorder Family Caregivers

Family caregivers of persons with bipolar disorder experience considerable stress. Yet, studies have not examined whether their stress differs by race and gender. This preliminary analysis of baseline data from 228 African American and White family caregivers of adults with bipolar disorder who were enrolled in a randomized controlled trial examined race and gender differences on two validated self-report measures of psychological stress (caregiver burden and caregiver reactions) and an electrocardiography device used to capture heart rate variability (HRV). No statistically significant differences were found by race or gender on either measure of psychological stress. African American caregivers had significantly lower scores on two indices of HRV compared to White caregivers. Women had significantly lower scores on one index of HRV compared to men. Low HRV indicates greater stress and mortality risk. Future research should include HRV to measure caregiver stress and implement relevant interventions.

The semantics of microglia activation: neuroinflammation, homeostasis, and stress

Microglia are emerging as critical regulators of neuronal function and behavior in nearly every area of neuroscience. Initial reports focused on classical immune functions of microglia in pathological contexts, however, immunological concepts from these studies have been applied to describe neuro-immune interactions in the absence of disease, injury, or infection. Indeed, terms such as 'microglia activation' or 'neuroinflammation' are used ubiquitously to describe changes in neuro-immune function in disparate contexts; particularly in stress research, where these terms prompt undue comparisons to pathological conditions. This creates a barrier for investigators new to neuro-immunology and ultimately hinders our understanding of stress effects on microglia. As more studies seek to understand the role of microglia in neurobiology and behavior, it is increasingly important to develop standard methods to study and define microglial phenotype and function. In this review, we summarize primary research on the role of microglia in pathological and physiological contexts. Further, we propose a framework to better describe changes in microglia1 phenotype and function in chronic stress. This approach will enable more precise characterization of microglia in different contexts, which should facilitate development of microglia-directed therapeutics in psychiatric and neurological disease.

From the Molecular Mechanism to Pre-clinical Results: Anti-epileptic Effects of Fingolimod

Epilepsy is a devastating neurological condition characterized by long-term tendency to generate unprovoked seizures, affecting around 1-2% of the population worldwide. Epilepsy is a serious health concern which often associates with other neurobehavioral comorbidities that further worsen disease conditions. Despite tremendous research, the mainstream anti-epileptic drugs (AEDs) exert only symptomatic relief leading to 30% of untreatable patients. This reflects the complexity of the disease pathogenesis and urges the precise understanding of underlying mechanisms in order to explore novel therapeutic strategies that might alter the disease progression as well as minimize the epilepsy-associated comorbidities. Unfortunately, the development of novel AEDs might be a difficult process engaging huge funds, tremendous scientific efforts and stringent regulatory compliance with a possible chance of end-stage drug failure. Hence, an alternate strategy is drug repurposing, where anti-epileptic effects are elicited from drugs that are already used to treat non-epileptic disorders.

Herein, we provide evidence of the anti-epileptic effects of Fingolimod (FTY720), a modulator of sphingosine-1-phosphate (S1P) receptor, USFDA approved already for Relapsing-Remitting Multiple Sclerosis (RRMS). Emerging experimental findings suggest that Fingolimod treatment exerts disease-modifying anti-epileptic effects based on its anti-neuroinflammatory properties, potent neuroprotection, anti-gliotic effects, myelin protection, reduction of mTOR signaling pathway and activation of microglia and astrocytes. We further discuss the underlying molecular crosstalk associated with the anti-epileptic effects of Fingolimod and provide evidence for repurposing Fingolimod to overcome the limitations of current AEDs.

Tumor pyruvate kinase M2 modulators: a comprehensive account of activators and inhibitors as anticancer agents

Pyruvate kinase M2 (PKM2) catalyzes the conversion of phosphoenolpyruvate (PEP) to pyruvate. It plays a central role in the metabolic reprogramming of cancer cells and is expressed in most human tumors. It is essential in indiscriminate proliferation, survival, and tackling apoptosis in cancer cells. This positions PKM2 as a hot target in cancer therapy. Despite its well-known structure and several reported modulators targeting PKM2 as activators or inhibitors, a comprehensive review focusing on such modulators is lacking. Herein we summarize modulators of PKM2, the assays used to detect their potential, the preferable tense (T) and relaxed (R) states in which the enzyme resides, lacunae in existing modulators, and several strategies that may lead to effective anticancer drug development targeting PKM2.

Physical Stress Induced Reduction of Proliferating Cells and Differentiated Neuroblasts Is Ameliorated by Fermented Laminaria japonica Extract Treatment

Laminaria japonica is widely cultivated in East Asia, including South Korea. Fucoidan, a main component of L. japonica, protects neurons from neurological disorders such as ischemia and traumatic brain injury. In the present study, we examined the effects of extract from fermented L. japonica on the reduction of proliferating cells and neuroblasts in mice that were physically (with electric food shock) or psychologically (with visual, auditory and olfactory sensation) stressed with the help of a communication box. Vehicle (distilled water) or fermented L. japonica extract (50 mg/kg) were orally administered to the mice once a day for 21 days. On the 19th day of the treatment, physical and psychological stress was induced by foot shock using a communication box and thereafter for three days. Plasma corticosterone levels were significantly increased after exposure to physical stress and decreased Ki67 positive proliferating cells and doublecortin immunoreactive neuroblasts. In addition, western blot analysis demonstrated that physical stress as well as psychological stress decreased the expression levels of brain-derived neurotrophic factor (BDNF) and the number of phosphorylated cAMP response element binding protein (pCREB) positive nuclei in the dentate gyrus. Fermentation of L. japonica extract significantly increased the contents of reduced sugar and phenolic compounds. Supplementation with fermented L. japonica extract significantly ameliorated the increases of plasma corticosterone revels and decline in the proliferating cells, neuroblasts, and expression of BDNF and pCREB in the physically stressed mice. These results indicate that fermented L. japonica extract has positive effects in ameliorating the physical stress induced reduction in neurogenesis by modulating BDNF and pCREB expression in the dentate gyrus.

A scoping review of interventions targeting allostatic load

Allostatic load (AL) is the manifestation of cumulative responses to chronic stress exposure. Numerous studies have shown the importance of AL in understanding disease risks. Yet little is known about existing interventions that target AL specifically. We aimed to address this gap by identifying interventions targeting AL and determining the success of these interventions in improving biological functioning. We searched five electronic databases using variations of two concepts: AL and programs or interventions. We included original research reports that focused on AL as an outcome. We excluded work that focused on a single indicator, not written in English or did not implement an intervention. The Template for Intervention Description and Replication checklist guided our intervention critique and synthesis. Six articles were included, with sample size across the interventions ranging between 2 and 733. Despite inconsistencies in the selection of AL indicators and scoring of AL, all four body systems were represented in all the studies. Four interventions showed significant improvement in Al (as indicated by a decrease in AL score) as early as 7 weeks. More interventions targeting Al are needed. The reduction in AL scores among four of the six interventions suggests that Al could be a biological outcome measure that is sensitive to change in response to interventions. This has significant clinical and research implications. Future studies are needed to examine whether AL serves as a mediator in the effects of the intervention on improving clinical manifestations of diseases.

Social mobility, accumulation of disadvantages and health. An analysis with retrospective data from the GSOEP (2002-14)

BACKGROUND

Socioeconomic position (SEP) in different life stages is related to health-related quality of life (HRQoL). Yet, research on the relevance of life course processes is scarce. This study aims to analyse the association between accumulation of disadvantages, social mobility and HRQoL.

METHODS

Analyses were conducted using population-averaged panel-data models and are based on data from the German Socio-Economic Panel 2002-14, including retrospective biographical information, comprising 25 473 observations from 8666 persons. Intergenerational and intragenerational mobility included the occupational positions in childhood (parental position), first job and middle age. Accumulation of disadvantages was measured using an accumulation index. HRQoL was assessed using the Mental and Physical Component Summary Scores of the SF12v2.

RESULTS

Accumulation of disadvantages was the main predictor for the Physical Component Summary in mid-age. Men and women in a stable low SEP or with a steep downward mobility showed the least favourable physical HRQoL. This holds for intergenerational and intragenerational mobility. Mental HRQoL did not seem to be associated with accumulation or social mobility.

CONCLUSION

The results show that physical HRQoL is related to social mobility and accumulation of (dis-)advantages. Further research is needed thoroughly analysing this association.

Animal models of major depression: drawbacks and challenges

Major depression is a leading contributor to the global burden of disease. This situation is mainly related to the chronicity and/or recurrence of the disorder, and to poor response to antidepressant therapy. Progress in this area requires valid animal models. Current models are based either on manipulating the environment to which rodents are exposed (during the developmental period or adulthood) or biological underpinnings (i.e. gene deletion or overexpression of candidate genes, targeted lesions of brain areas, optogenetic control of specific neuronal populations, etc.). These manipulations can alter specific behavioural and biological outcomes that can be related to different symptomatic and pathophysiological dimensions of major depression. However, animal models of major depression display substantial shortcomings that contribute to the lack of innovative pharmacological approaches in recent decades and which hamper our capabilities to investigate treatment-resistant depression. Here, we discuss the validity of these models, review putative models of treatment-resistant depression, major depression subtypes and recurrent depression. Furthermore, we identify future challenges regarding new paradigms such as those proposing dimensional rather than categorical approaches to depression.

From Healthy Aging to Frailty: In Search of the Underlying Mechanisms

Population aging is accelerating rapidly worldwide, from 461 million people older than 65 years in 2004 to an estimated 2 billion people by 2050, leading to critical implications for the planning and delivery of health and social care. The most problematic expression of population aging is the clinical condition of frailty, which is a state of increased vulnerability that develops as a consequence of the accumulation of microscopic damages in many physiological systems that lead to a striking and disproportionate change in health state, even after an apparently small insult. Since little is known about the biology of frailty, an important perspective to understand this phenomenon is to establish how the alterations that physiologically occur during a condition of healthy aging may instead promote cumulative decline with subsequent depletion of homoeostatic reserve and increase the vulnerability also after minor stressor events. In this context, the present review aims to provide a description of the molecular mechanisms that, by having a critical impact on behavior and neuronal function in aging, might be relevant for the development of frailty. Moreover, since these biological systems are also involved in the coping strategies set in motion to respond to environmental challenges, we propose a role for lifestyle stress as an important player to drive frailty in aging.

Stress adaptation in older adults with and without cognitive impairment: an fMRI pattern-based similarity analysis

BACKGROUND

The capacity to adapt to environmental stressors is essential for older adults' health and well-being. It is unclear how cognitive impairment may disrupt the capacity. Here we examined the relationship between self-perceptions of stress and the neurobiological response to a laboratory model of stress adaptation in amnestic mild cognitive impairment (aMCI), a group at high risk for dementia.

RESULTS

aMCI group and cognitively healthy controls did not differ in neurobiological acute stress recovery (indexed by similarity in neural patterns at baseline and after recovery from cognitive challenges). However, compared to controls, aMCI group had significantly lower scores on PSS-PW. Notably, higher PSS-PW was associated with greater acute neural recovery in controls, but not aMCI.

METHODS

We assessed self-perceptions of stress adaptation with the Perceived Stress Scale subscales, measuring perceived helplessness (i.e., negatively worded items, PSS-NW) and self-efficacy (i.e., positively worded items, PSS-PW) in response to stress. At a subsequent laboratory fMRI visit, we indexed neurobiological stress adaptation by assessing and comparing functional network connectivity at baseline and immediately following, and after recovery from, cognitive challenges.

CONCLUSIONS

Studying stress adaptation in aMCI may shed light on pathways that contribute to the onset and progress of cognitive deterioration in aging.

Socioeconomic factors and mortality in patients with atrial fibrillation-a cohort study in Swedish primary care

Background

Preventing ischaemic stroke attracts significant focus in atrial fibrillation (AF) cases. Less is known on the association between socioeconomic factors and mortality and cardiovascular outcomes in patients with AF.

Methods

Our study population included adults (n=12 283) ≥45 years diagnosed with AF at 75 primary care centres in Sweden 2001-07. Cox regression was used to calculate hazard ratios (HRs) with 95% confidence intervals (CIs) for the association between the exposures educational level, marital status, neighbourhood socioeconomic status and the outcomes all-cause mortality, after adjustment for age, and comorbid cardiovascular conditions.

Results

During a mean of 5.8 years (SD 2.4) of follow-up, 3954 (32.3%) patients had died; 1971 were women (35.0%) and 1983 were men (29.8%). Higher educational level was associated with a reduced mortality in fully adjusted models: HR 0.85 (95% CI 0.77-0.96) for secondary school in men, HR 0.73 (95% CI 0.60-0.88) for college/university in women, and HR 0.82 (95% CI 0.71-0.94) for college/university in men, compared to primary school. Unmarried men and divorced men had an increased risk of death, compared with married men: HR 1.25 (95% CI 1.05-1.50), and HR 1.23 (95% CI 1.07-1.42), respectively. College/university education level was also associated with lower risk of myocardial infarction in men and women, and lower risk of congestive heart failure in women.

Conclusion

More attention could be paid to individuals of lower levels of formal education, and unmarried men, in order to provide timely management for AF and prevent its debilitating complications.

The rat cumulative allostatic load measure (rCALM): a new translational assessment of the burden of stress

Determinants of lifetime health are complex and emphasize the need for robust predictors of disease risk. Allostatic load (AL) has become a clinical framework to estimate the cumulative biological burden associated with chronic stress. To assist knowledge translation in the developmental origins of health and disease field, clinically valid methods for reliable AL assessment in experimental models are urgently needed. Here, we introduce the rat cumulative allostatic load measure (rCALM), as a new preclinical knowledge translation tool to assess the burden of chronic stress. First, we identified an array of stress-associated physiological markers that are particularly sensitive to hypothalamic-pituitary-adrenal axis dysregulation by ancestral prenatal stress. Second, we determined which of these markers are susceptible to an intervention by environmental enrichment (EE) to mitigate AL. The markers most responsive to stress and EE therapy were assembled to become operationalized in the rCALM. Third, the new rCALM was validated for the ability to indicate future disease risks. The results show that the rCALM estimates the burden of chronic stress and serves as a proxy to estimate stress resilience and vulnerability to disease. Using the rCALM we showed that enrichment therapy can offset the adverse health outcomes linked to a high AL. Thus, the rCALM provides a model for the development of new test strategies that facilitate knowledge translation in preclinical animal models.

Aberrant Amygdala-dependent Fear Memory in Corticosterone-treated Mice

Anxiety disorder is a major psychiatric disorder characterized by fear, worry, and excessive rumination. However, the molecular mechanisms underlying neural plasticity and anxiety remain unclear. Here, we utilized a mouse model of anxiety-like behaviors induced by the chronic administration of corticosterone (CORT) to determine the exact mechanism of each region of the fear circuits in the anxiety disorders. Chronic CORT-treated mice showed a significant increase in anxiety-related behaviors as assessed by the elevated plus maze, light-dark, open-field, and marble-burying tasks. In addition, chronic CORT-treated mice exhibited abnormal amygdala-dependent tone-induced fear memory but normal hippocampus-dependent contextual memory. Consistent with amygdala hyperactivation, chronic CORT-treated mice showed significantly increased numbers of c-Fos-positive cells in the basolateral amygdala (BLA) after tone stimulation. Long-term potentiation (LTP) was markedly enhanced in the BLA of chronic CORT-treated mice compared to that of vehicle-treated mice. Immunoblot analyses revealed that autophosphorylation of Ca²⁺/calmodulin-dependent protein kinase (CaMK) IIα at threonine 286 and phosphorylation of cyclic-adenosine-monophosphate response-element-binding protein (CREB) at serine 133 were markedly increased in the BLA of chronic CORT-treated mice after tone stimulation. The protein and mRNA levels of brain-derived neurotrophic factor (BDNF) also significantly increased. Our findings suggest that increased CaMKII activity and synaptic plasticity in the BLA likely account for the aberrant amygdala-dependent fear memory in chronic CORT-treated mice.

The effects of protective factors and adverse childhood experiences on behavioral health services use: Findings from a population-based sample

Adverse childhood experiences (ACEs) are linked to later life health problems such as behavioral health (BH) service use but less is known about how to counter this association. Using a population based sample of 807 adults, we examined the effects of protective factors in countering this association. ACEs were associated with increased BH service use while protective factors were associated with decreased BH service use. However, no significant interaction effect was found. Research is needed to develop a better measure of protective factors. Social workers need to be aware of ACE prevalence among clients and can foster protective factors.

Revisiting nicotine’s role in the ageing brain and cognitive impairment

Brain ageing is a complex process which in its pathologic form is associated with learning and memory dysfunction or cognitive impairment. During ageing, changes in cholinergic innervations and reduced acetylcholinergic tonus may trigger a series of molecular pathways participating in oxidative stress, excitotoxicity, amyloid-β toxicity, apoptosis, neuroinflammation, and perturb neurotrophic factors in the brain. Nicotine is an exogenous agonist of nicotinic acetylcholine receptors (nAChRs) and acts as a pharmacological chaperone in the regulation of nAChR expression, potentially intervening in age-related changes in diverse molecular pathways leading to pathology. Although nicotine has therapeutic potential, paradoxical effects have been reported, possibly due to its inverted U-shape dose-response effects or pharmacokinetic factors. Additionally, nicotine administration should result in optimum therapeutic effects without imparting abuse potential or toxicity. Overall, this review aims to compile the previous and most recent data on nicotine and its effects on cognition-related mechanisms and age-related cognitive impairment.

Insights into the background of autonomic medicine

Knowledge of the physiology underlying the autonomic nervous system is pivotal for understanding autonomic dysfunction in clinical practice. Autonomic dysfunction may result from primary modifications of the autonomic nervous system or be secondary to a wide range of diseases that cause severe morbidity and mortality. Together with a detailed history and physical examination, laboratory assessment of autonomic function is essential for the analysis of various clinical conditions and the establishment of effective, personalized and precise therapeutic schemes. This review summarizes the main aspects of autonomic medicine that constitute the background of cardiovascular autonomic dysfunction.

Beneficial effect of fluoxetine treatment aganist psychological stress is mediated by increasing BDNF expression in selected brain areas

SSRI antidepressant fluoxetine is widely used to treat psychological stress related disorders, however the underlying working mechanisms is not fully understood, as SSRIs can rapidly increase the extracellular serotonin levels but it normally takes weeks to reveal their therapeutic effect in the stress-related psychological disorders. Our previous study demonstrated that purely psychological stress without any physic stimuli induces a biphasic change in the expression of brain-derived neurotrophic factor (BDNF), which immediately decrease and then gradually increase after the stress; and that the latter BDNF increase in response to the psychological stress involves the activation of serotonin system. To investigate the role of BDNF in the fluoxetine treatment for stress-related psychological disorders, we examined the mRNA and protein levels of BDNF in the brain of Sprague-Dawley (SD) rats, which were pretreated with fluoxetine at 10 mg/kg or vehicle solution for 14 days, over 24 hour after an acute psychological stress exposure. In situ hybridization and immunohistochemistry were performed to detect the expression of BDNF at different time points in various brain regions after the psychological stress. We found that fluoxetine treatment completely blocked the BDNF decrease induced by the psychological stress, and also enhanced the gradual increase in the expression of BDNF in most of the brain regions except VTA after the psychological stress. The results suggest that the enhancement in BDNF levels induced by chronic fluoxetine treatment mediates the therapeutic effect against psychological stress.

An Update on CRF Mechanisms Underlying Alcohol Use Disorders and Dependence

Alcohol is the most commonly used and abused substance worldwide. The emergence of alcohol use disorders, and alcohol dependence in particular, is accompanied by functional changes in brain reward and stress systems, which contribute to escalated alcohol drinking and seeking. Corticotropin-releasing factor (CRF) systems have been critically implied in the transition toward problematic alcohol drinking and alcohol dependence. This review will discuss how dysregulation of CRF function contributes to the vulnerability for escalated alcohol drinking and other consequences of alcohol consumption, based on preclinical evidence. CRF signaling, mostly via CRF1 receptors, seems to be particularly important in conditions of excessive alcohol taking and seeking, including during early and protracted withdrawal, relapse, as well as during withdrawal-induced anxiety and escalated aggression promoted by alcohol. Modulation of CRF1 function seems to exert a less prominent role over low to moderate alcohol intake, or to species-typical behaviors. While CRF mechanisms in the hypothalamic-pituitary-adrenal axis have some contribution to the neurobiology of alcohol abuse and dependence, a pivotal role for extra-hypothalamic CRF pathways, particularly in the extended amygdala, is well characterized. More recent studies further suggest a direct modulation of brain reward function by CRF signaling in the ventral tegmental area, nucleus accumbens, and the prefrontal cortex, among other structures. This review will further discuss a putative role for other components of the CRF system that contribute for the overall balance of CRF function in reward and stress pathways, including CRF2 receptors, CRF-binding protein, and urocortins, a family of CRF-related peptides.

Incorporating Persistent Pain in Phenotypic Frailty Measurement and Prediction of Adverse Health Outcomes

BACKGROUND

Frailty, a syndrome of physiological deficits, is prevalent among older adults and predicts elevated risk of adverse health outcomes. Although persistent pain predicts similar risk, it is seldom considered in frailty measurement. This article evaluated the construct and predictive validity of including persistent pain in phenotypic frailty measurement.

METHODS

Frailty and persistent pain were operationalized using data from the Health and Retirement Study (2006-2012 waves). Among a subset of adults aged 65 and older (n = 3,652), we used latent class analysis to categorize frailty status and to evaluate construct validity. Using Cox proportional hazards models, we compared time to incident adverse outcomes (death, fall, hospitalization, institutionalization, and functional disability) between frailty classes determined by either including or excluding persistent pain as a frailty component.

RESULTS

In latent class models, persistent pain occurred with other frailty components in patterns consistent with a medical syndrome. Frail and intermediately frail classes determined by including persistent pain were more strongly associated with all adverse outcomes compared with frail and intermediately frail classes determined excluding persistent pain. Frail respondents had significantly greater risk of death compared with nonfrail respondents when frailty models included rather than excluded persistent pain (respectively, hazard ratio [HR] = 3.87, 95% confidence interval [CI] = 2.99-5.00 (including pain); HR = 2.10, 95% CI = 1.71-2.59 (excluding pain).

CONCLUSIONS

Findings support consideration of persistent pain as a component of the frailty phenotype. Persistent pain assessment may provide an expedient method to enhance frailty measurement and improve prediction of adverse outcomes.

Complementary and Alternative Health Care and the Home Care Population

As the use of complementary and alternative medicine has steadily risen over recent years, it is safe to assume a significant portion of the home care population has or is using health treatment modalities outside of the conventional Western medical model. The authors provide an overview of complementary and alternative medicine and three modalities commonly encountered and occasionally practiced by nurses and other licensed health care professionals: acupuncture, Reiki, and botanical healing.

Factors related to heart rate variability among firefighters

OBJECTIVES

The aim of this study was to investigate factors associated with heart rate variability in firefighters working in a metropolitan city in South Korea.

METHODS

Self-administered questionnaires including Korean Occupational Stress Scale (KOSS) as well as surveys collecting socio-demographic characteristics and work-related factors were given to 962 firefighters. After exclusion for missing data, 645 firefighters were included, and analysis of covaiance adjusted for the general risk factors and job characteristics were used to assess the relationship between heart rate variability and associated factors.

RESULTS

SDNN and RMSSD and were decreased in the area of occupational climate of the group with high job stress (p = 0.027, p = 0.036). HF(ln) was decreased in the area of organizational system and occupational climate of the group with high stress that statistically significant level (p = 0.034, p = 0.043).

CONCLUSIONS

Occupational climate and organizational system are associated with reduction of heart rate variability. Preventive medical care plans for cardiovascular disease of firefighters through the analysis and evaluation of job stress factors are needed.

Allostatic load in women with a history of low birth weight infants: the national health and nutrition examination survey

BACKGROUND

The purpose of our study was to determine whether women of reproductive age with history of low birth weight (LBW) deliveries have higher allostatic load (AL), a measure of the cumulative toll of chronic stress, than those with normal-weight deliveries.

METHODS

We used data from women ages 17-35 who responded to the National Health and Nutrition Examination Survey (NHANES) reproductive-health questionnaire, 1999-2006. Women reported history of LBW infants and those who were preterm. We classified preterm-LBW and term-LBW as surrogates for preterm birth (PTB) and small for gestational age (SGA), respectively. Normal weight included those without LBW infant history. We utilized nine biomarkers measured in NHANES to determine AL and used linear regression to compare unadjusted and adjusted means.

RESULTS

We identified 877 women divided among SGA (2%), PTB (10%), and normal groups (88%). The SGA group had higher unadjusted and adjusted AL scores than did the normal group (2.82 ± 0.35 vs. 1.92 ± 0.07, p=0.011); women in the PTB group had higher AL scores than did the referent in adjusted analyses (2.58 ± 0.21 vs. 1.92 ± 0.07, p=0.001).

CONCLUSIONS

Women with history of SGA or PTB had higher AL than did those with normal birth weight outcomes. This suggests a link between adverse pregnancy outcomes, chronic stress, and subclinical disease.

Neighbourhood socio-economic status and all-cause mortality in adults with atrial fibrillation: A cohort study of patients treated in primary care in Sweden

OBJECTIVE

Our aim was to study the potential impact of neighbourhood socio-economic status (SES) on all-cause mortality in patients with atrial fibrillation (AF) treated in primary care.

METHODS

Study population included adults (n=12,283) of 45 years and older diagnosed with AF in 75 primary care centres in Sweden. Association between neighbourhood SES and all-cause mortality was explored using Cox regression analysis, with hazard ratios (HRs) and 95% confidence intervals (95% CIs), and by Laplace regression where years to death (95% CI) of the first 10% of the participants were used as an outcome. All models were conducted in both men and women and adjusted for age, educational level, marital status, change of neighbourhood status, cardiovascular co-morbidities, anticoagulant treatment and statin treatment. High- and low-neighbourhood SES were compared with middle SES as reference group.

RESULTS

After adjustments for potential confounders, higher relative risk of all-cause mortality (HR 1.49, 95% CI 1.13-1.96) was observed in men living in low SES neighbourhoods compared to those from middle SES neighbourhoods. The results were confirmed using Laplace regression; the time until the first 10% of the men in low SES neighbourhoods died was 1.45 (95% CI 0.48-2.42) years shorter than for the men in middle SES neighbourhoods.

CONCLUSIONS

Increased rates of heart disease and subsequent mortality among adults in deprived neighbourhoods raise important clinical and public health concerns. These findings could serve as an aid to policy-makers when allocating resources in primary health care settings as well as to clinicians who encounter patients in deprived neighbourhoods.

Temperament type specific metabolite profiles of the prefrontal cortex and serum in cattle

In the past decade the number of studies investigating temperament in farm animals has increased greatly because temperament has been shown not only to affect handling but also reproduction, health and economically important production traits. However, molecular pathways underlying temperament and molecular pathways linking temperament to production traits, health and reproduction have yet to be studied in full detail. Here we report the results of metabolite profiling of the prefrontal cortex and serum of cattle with distinct temperament types that were performed to further explore their molecular divergence in the response to the slaughter procedure and to identify new targets for further research of cattle temperament. By performing an untargeted comprehensive metabolite profiling, 627 and 1097 metabolite features comprising 235 and 328 metabolites could be detected in the prefrontal cortex and serum, respectively. In total, 54 prefrontal cortex and 51 serum metabolite features were indicated to have a high relevance in the classification of temperament types by a sparse partial least square discriminant analysis. A clear discrimination between fearful/neophobic-alert, interested-stressed, subdued/uninterested-calm and outgoing/neophilic-alert temperament types could be observed based on the abundance of the identified relevant prefrontal cortex and serum metabolites. Metabolites with high relevance in the classification of temperament types revealed that the main differences between temperament types in the response to the slaughter procedure were related to the abundance of glycerophospholipids, fatty acyls and sterol lipids. Differences in the abundance of metabolites related to C21 steroid metabolism and oxidative stress indicated that the differences in the metabolite profiles of the four extreme temperament types could be the result of a temperament type specific regulation of molecular pathways that are known to be involved in the stress and fear response.

Chronic subordinate colony housing paradigm: a mouse model to characterize the consequences of insufficient glucocorticoid signaling

Chronic, in particular chronic psychosocial, stress is a burden of modern societies and known to be a risk factor for numerous somatic and affective disorders (in detail referenced below). However, based on the limited existence of appropriate, and clinically relevant, animal models for studying the effects of chronic stress, the detailed behavioral, physiological, neuronal, and immunological mechanisms linking stress and such disorders are insufficiently understood. To date, most chronic stress studies in animals employ intermittent exposure to the same (homotypic) or to different (heterotypic) stressors of varying duration and intensity. Such models are only of limited value, since they do not adequately reflect the chronic and continuous situation that humans typically experience. Furthermore, application of different physical or psychological stimuli renders comparisons to the mainly psychosocial stressors faced by humans, as well as between the different stress studies almost impossible. In contrast, rodent models of chronic psychosocial stress represent situations more akin to those faced by humans and consequently seem to hold more clinical relevance. Our laboratory has developed a model in which mice are exposed to social stress for 19 continuous days, namely the chronic subordinate colony housing (CSC) paradigm, to help bridge this gap. The main aim of the current review article is to provide a detailed summary of the behavioral, physiological, neuronal, and immunological consequences of the CSC paradigm, and wherever possible relate the findings to other stress models and to the human situation.

Heart rate variability in male shift workers in automobile manufacturing factories in South Korea

PURPOSE

The aim of this study was to determine the effect of circadian rhythm disruption on cardiovascular autonomic regulation by examining potential differences in heart rate variability (HRV) between day- and night-shift workers.

METHODS

The study population consisted of 162 workers who worked both day and night shifts in two automobile manufacturing companies who underwent ambulatory 24-h electrocardiogram recording and completed questionnaires and sleep diaries. Both time and frequency domain indices of HRV were compared.

RESULTS

HRV parameters (mean RR, SDNN, RMSSD, pNN50, TP, HF, LF, LF/HF ratio) reflecting sympathetic and parasympathetic modulation varied less with activity in night-shift workers.

CONCLUSIONS

Circadian rhythm-mediated changes in autonomic regulation of the cardiovascular system were blunted in night-shift workers, which could contribute to an increased risk for cardiovascular disease in overnight workers.

Synaptic rewiring of stress-sensitive neurons by early-life experience: a mechanism for resilience?

Genes and environment interact to influence cognitive and emotional functions throughout life. Early-life experiences in particular contribute to vulnerability or resilience to a number of emotional and cognitive illnesses in humans. In rodents, early-life experiences directly lead to resilience or vulnerability to stress later in life, and influence the development of cognitive and emotional deficits. The mechanisms for the enduring effects of early-life experiences on cognitive and emotional outcomes are not completely understood. Here, we present emerging information supporting experience-dependent modulation of the number and efficacy of synaptic inputs onto stress-sensitive neurons. This synaptic 'rewiring', in turn, may influence the expression of crucial neuronal genes. The persistent changes in gene expression in resilient versus vulnerable rodent models are likely maintained via epigenetic mechanisms. Thus, early-life experience may generate resilience by altering synaptic input to neurons, which informs them to modulate their epigenetic machinery.

Stress-Related Changes in Attentional Bias to Social Threat in Young Adults: Psychobiological Associations with the Early Family Environment

This study investigated the association of chronic childhood stress exposure with acute stress-related attentional alterations that have been previously linked to vulnerability to mental and physical illness in early adulthood. Participants were randomized in a crossover design to complete both a mild laboratory social stress task and a computerized task assessing attentional bias to socially threatening words. Salivary cortisol was measured throughout the study. Exposure to acute laboratory stress altered attentional processing, and this relationship was moderated by chronic childhood stress exposure. Also, a positive association between cortisol reactivity and attentional bias was observed, with cortisol reactivity negatively related to childhood chronic stress exposure. While previous work has supported a role for early chronic stress exposure in influencing acute stress reactivity, this work provides initial insight into how both prior chronic childhood stress and current acute stress together relate to the attentional gateway and may be associated with stress adaptation and psychological vulnerability into adulthood.

Sex- and age-specific differences in relaxin family peptide receptor expression within the hippocampus and amygdala in rats

Relaxin is an essential pregnancy-related hormone with broad peripheral effects mediated by activation of relaxin-like family peptide 1 receptors (RXFP1). More recent studies suggest an additional role for relaxin as a neuropeptide, with RXFP1 receptors expressed in numerous brain regions. Neurons in an area of the brainstem known as the nucleus incertus (NI) produce relaxin 3 (RLN3), the most recently identified neuropeptide in the relaxin family. RLN3 has been shown to activate both RXFP1 and relaxin-like family peptide receptor 3 (RXFP3) receptor subtypes. Studies suggest wide-ranging neuromodulatory effects of both RXFP1 and RXFP3 activation, although to date the majority of studies have been conducted in young males. In the current study, we examined potential sex- and age-related changes in RLN3 gene expression in the NI as well as RXFP1 and RXFP3 gene expression in the dorsal hippocampus (HI), ventral hippocampus (vHI) and amygdala (AMYG) using young adult (9-12weeks) and middle-aged (9-12months) male and female rats. In addition, regional changes in RXFP1 and RXFP3 protein expression were examined in the CA1, CA2/CA3 and dentate gyrus (DG) as well as within basolateral (BLA), central (CeA), and medial (MeA) amygdaloid nuclei. In the NI, RLN3 showed an age-related decrease in males. In the HI, only the RXFP3 receptor showed an age-related change in gene expression, however, both receptor subtypes showed age-related changes in protein expression that were region specific. Additionally, while gene and protein expression of both receptors increased with age in AMYG, these effects were both region- and sex-specific. Finally, overall males displayed a greater number of cells that express the RXFP3 protein in all of the amygdaloid nuclei examined. Cognitive and emotional processes regulated by activity within the HI and AMYG are modulated by both sex and age. The vast majority of studies exploring the influence of sex on age-related changes in the HI and AMYG have focused on sex hormones, with few studies examining the role of neuropeptides. The current findings suggest that changes in relaxin family peptides may contribute to the significant sex differences observed in these brain regions as a function of aging.

Cortisol increase in empathic stress is modulated by emotional closeness and observation modality

Stress disorders are among the most commonly occurring of all mental disorders. In this context, the question arises whether the stress inevitably unfolding around us has the potential to "contaminate" and compromise us. In the current multi-center study, we investigate the existence of such empathic stress (defined as a full-blown physiological stress response that arises solely by observing a target undergo a stressful situation), and whether empathic stress permeates to the core of the stress system, the hypothalamic-pituitary-adrenal (HPA) axis. Additionally, we investigate whether empathic stress responses may be modulated by the familiarity between observer and target (partners vs. strangers), the modality of observation (real-life vs. virtual) and observer sex (female vs. male). Participants were tested in dyads, paired with a loved one or a stranger of the opposite sex. While the target of the dyad (n=151) was exposed to a psychosocial stressor, the observer (n=211) watched through a one-way mirror or via live video transmission. Overall, 26% of the observers displayed physiologically significant cortisol increases. This empathic stress was more pronounced in intimate observer-target dyads (40%) and during the real-life representation of the stressor (30%). Empathic stress was further modulated by interindividual differences in empathy measures. Despite the higher prevalence of empathic stress in the partner and real-life observation conditions, significant cortisol responses also emerged in strangers (10%) and the virtual observation modality (24%). The occurrence of empathic stress down to the level of HPA-axis activation, in some cases even in total strangers and when only virtually witnessing another's distress, may have important implications for the development of stress-related diseases.

Exogenous and endogenous opioid-induced pain hypersensitivity in different rat strains

BACKGROUND

Opioid-induced hyperalgesia (OIH) is a recognized complication of opioid use that may facilitate the development of exaggerated postoperative pain.

OBJECTIVE

To examine the role of genetic factors on OIH by comparing four rat strains. Because the authors previously reported that the endogenous opioids released during non-nociceptive environmental stress induce latent pain sensitization, genetic and environmental factor interactions were also evaluated.

METHODS

First, the propensity of Sprague Dawley, Wistar, Lewis and Fischer rats to develop OIH following single or repeated fentanyl exposures was compared by measuring the nociceptive threshold using the paw pressure vocalization test. Second, Sprague Dawley and Fischer rats were exposed to a series of three non-nociceptive environmental stress sessions to evaluate the ability of endogenous opioids to enhance hyperalgesia associated with a carrageenan-induced hind-paw inflammation test performed two weeks later.

RESULTS

Sprague Dawley, Wistar and Lewis rats exhibited OIH, although differences were observed. OIH was not observed in Fischer rats. Inflammatory hyperalgesia enhancement induced through previous stress in Sprague Dawley rats was not observed in Fischer rats.

CONCLUSIONS

The pain level not only reflects nociceptive inputs but also depends on both the history and genetic factors of the individual. Genetic and environmental models may provide new insights into the mechanisms that underlie individual differences observed in postoperative pain.

Age-related differences in oligodendrogenesis across the dorsal-ventral axis of the mouse hippocampus

Oligodendrocyte precursor cells (OPCs) continue to divide and generate new oligodendrocytes (OLs) in the healthy adult brain. Although recent studies have indicated that adult oligodendrogenesis may be vital for the maintenance of normal brain function, the significance of adult oligodendrogenesis in brain aging remains unclear. In this study, we report a stereological estimation of age-related oligodendrogenesis changes in the mouse hippocampus: the dorsal subdivision is related to learning and memory, while the ventral subdivision is involved in emotional behaviors. To identify OPCs and OLs, we used a set of molecular markers, OL lineage transcription factor (Olig2) and platelet-derived growth factor receptor-alpha (PDGFαR). Intracellular dye injection shows that PDGFαR+/Olig2+ cells and PDGFαR-/Olig2+ cells can be defined as OPCs and OLs, respectively. In the dorsal Ammon's horn, the numbers of OPCs decreased with age, while those of OLs remained unchanged during aging. In the ventral Ammon's horn, the numbers of OPCs and OLs generally decreased with age. Bromodeoxyuridine (BrdU) fate-tracing analysis revealed that the numbers of BrdU+ mitotic OPCs in the Ammon's horn remained unchanged during aging in both the dorsal and ventral subdivisions. Unexpectedly, the numbers of BrdU+ newly generated OLs increased with age in the dorsal Ammon's horn, but remained unchanged in the ventral Ammon's horn. Together, the numbers of OLs in the dorsal Ammon's horn may be maintained during aging by increased survival of adult born OLs, while the numbers of OLs in the ventral Ammon's horn may be reduced with age due to the lack of such compensatory mechanisms. These observations provide new insight into the involvement of adult oligodendrogenesis in age-related changes in the structure and function of the hippocampus.

Financial stress in late adulthood and diverse risks of incident cardiovascular disease and all-cause mortality in women and men

BACKGROUND

Financial stress may have adverse health effects. The main aim of this study was to investigate whether having a cash margin and living alone or cohabiting is associated with incident cardiovascular disease (CVD) and all-cause mortality.

METHODS

Representative population-based prospective cohort study of 60-year-old women (n = 2065) and men (n = 1939) in Stockholm County, Sweden. National registers were used to identify cases of incident CVD (n = 375) and all-cause mortality (n = 385). The presence of a cash margin was determined in the questionnaire with the following question: Would you, if an unexpected situation occurred, be able to raise 10,000 SEK within a week? (This was equivalent to US$ 1250 in 1998).

RESULTS

Compared with cohabiting women with a cash margin, the risk of all-cause mortality was higher among cohabiting women without a cash margin, with hazard ratios (HRs) of 1.97 (95% confidence interval (CI) 1.06-3.66). Using cohabiting men with cash margin as referent, single men without a cash margin were at an increased risk of both incident CVD and all-cause mortality: HR 2.84 (95% CI 1.61-4.99) and 2.78 (95% CI 1.69-4.56), respectively. Single men with cash margins still had an increased risk of all-cause mortality when compared with cohabiting men with a cash margin: HR 1.67 (95% CI 1.22-2.28).

CONCLUSIONS

Financial stress may increase the risks of incident CVD and all-cause mortality, especially among men. Furthermore these risks are likely to be greater in men living in single households and in women without cash margins. Living with a partner seems to protect men, but not women, from ill-health associated with financial stress due to the lack of a cash margin.

Puberty and adolescence as a time of vulnerability to stressors that alter neurobehavioral processes

Puberty and adolescence are major life transitions during which an individual's physiology and behavior changes from that of a juvenile to that of an adult. Here we review studies documenting the effects of stressors during pubertal and adolescent development on the adult brain and behavior. The experience of complex or compound stressors during puberty/adolescence generally increases stress reactivity, increases anxiety and depression, and decreases cognitive performance in adulthood. These behavioral changes correlate with decreased hippocampal volumes and alterations in neural plasticity. Moreover, stressful experiences during puberty disrupt behavioral responses to gonadal hormones both in sexual performance and on cognition and emotionality. These behavioral changes correlate with altered estrogen receptor densities in some estrogen-concentrating brain areas, suggesting a remodeling of the brain's response to hormones. A hypothesis is presented that activation of the immune system results in chronic neuroinflammation that may mediate the alterations of hormone-modulated behaviors in adulthood.

Psychological processing in chronic pain: a neural systems approach

Our understanding of chronic pain involves complex brain circuits that include sensory, emotional, cognitive and interoceptive processing. The feed-forward interactions between physical (e.g., trauma) and emotional pain and the consequences of altered psychological status on the expression of pain have made the evaluation and treatment of chronic pain a challenge in the clinic. By understanding the neural circuits involved in psychological processes, a mechanistic approach to the implementation of psychology-based treatments may be better understood. In this review we evaluate some of the principle processes that may be altered as a consequence of chronic pain in the context of localized and integrated neural networks. These changes are ongoing, vary in their magnitude, and their hierarchical manifestations, and may be temporally and sequentially altered by treatments, and all contribute to an overall pain phenotype. Furthermore, we link altered psychological processes to specific evidence-based treatments to put forth a model of pain neuroscience psychology.

Corticosteroid-related central nervous system side effects

Corticosteroids have been used since the 50s as anti-inflammatory and immunosuppressive drugs for the treatment of several pathologies such as asthma, allergy, rheumatoid arthritis, and dermatological disorders. Corticosteroids have three principal mechanisms of action: 1) inhibit the synthesis of inflammatory proteins blocking NF-kB, 2) induce the expression of anti-inflammatory proteins by IkB and MAPK phosphatase I, and 3) inhibit 5-lipoxygenase and cyclooxygenase-2. The efficacy of glucocorticoids in alleviating inflammatory disorders results from the pleiotropic effects of the glucocorticoid receptors on multiple signaling pathways. However, they have adverse effects: Growth retardation in children, immunosuppression, hypertension, hyperglycemia, inhibition of wound repair, osteoporosis, metabolic disturbances, glaucoma, and cataracts. Less is known about psychiatric or side effects on central nervous system, as catatonia, decreased concentration, agitation, insomnia, and abnormal behaviors, which are also often underestimated in clinical practice. The aim of this review is to highlight the correlation between the administration of corticosteroids and CNS adverse effects, giving a useful guide for prescribers including a more careful assessment of risk factors and encourage the use of safer doses of this class of drugs.

Metabolic syndrome: relative risk associated with post-traumatic stress disorder (PTSD) severity and antipsychotic medication use

BACKGROUND

In recent years, numerous lines of converging evidence have revealed an association between post-traumatic stress disorder (PTSD) and impaired physical health outcomes, including cardiovascular disease and metabolic syndrome. Although these findings have been interpreted as indicating a direct association of PTSD with metabolic syndrome and obesity, previous studies have not addressed the important confound of antipsychotic drug usage in this population. Second generation antipsychotic medications themselves are associated with metabolic syndrome and obesity, and it is unclear whether the common utilization of these drugs in PTSD may account for some if not all of the observed metabolic problems.

OBJECTIVE

The present study examined the relative contributions of PTSD severity and use of antipsychotic medications to risk of metabolic syndrome among veterans.

METHOD

Cross-sectional clinical data, including five factors representing metabolic syndrome, psychiatric diagnoses, and medications were gathered from 253 veterans enrolling in mental health services. We used a logistic regression model to measure the relative association of antipsychotic medication use and PTSD severity on risk of metabolic syndrome.

RESULTS

We found that antipsychotic medication usage was not uniquely associated with elevated risk of metabolic syndrome (Wald = 0.30, ns) when PTSD severity and other sociodemographic, psychiatric, and behavioral variables were accounted for. Furthermore, PTSD severity continued to be a significant and unique predictor of risk for metabolic syndrome (Wald = 4.04, p < 0.05).

CONCLUSIONS

These findings suggest that chronic and moderately severe PTSD, independent of antipsychotic medications, is associated with increased risk of metabolic syndrome.

A comparison of clinician-rated neuropsychological and self-rated cognitive assessments in patients with asthma and rheumatologic disorders

Although data are mixed, asthma and rheumatologic conditions may be associated with cognitive impairment. Medications may play a role because corticosteroids are associated with memory impairment. Therefore, an easily administered assessment of cognition would be useful in these patients. We assessed relationships between self-rated and clinician-rated cognitive performance and mood in patients with asthma and rheumatologic diseases. Participants included 31adults treated for asthma or rheumatologic disorders (17 receiving chronic prednisone therapy, and 14 not receiving prednisone). An objective assessment of a variety of cognitive domains was administered through clinician and patient-rated assessments of cognition. Composite scores for the objective (Global Clinical Rating [GCR]) and subjective (Neuropsychological Impairment Scale: Global Measure of Impairment [GMI]) measures of cognition were derived. Depression was assessed with the 17-item Hamilton Rating Scale for Depression (HRSD-17). A linear regression was conducted with GMI scores as dependent variable and GCR, HRSD-17 scores, and prednisone-use status, as independent variables. Significant differences between prednisone-treated patients and other patients were observed on the GCR, GMI, and HRSD-17. In the regression analysis, HRSD-17 scores, but not GCR scores, significantly predicted GMI scores. Prednisone-treated patients had higher levels of depressive symptoms and subjective and objective cognitive deficits than those not taking prednisone. In the combined patient groups, subjective cognitive assessment was more strongly related to depressive symptoms than objective cognition. Findings suggest physicians should be aware of the potential for cognitive deficits in patients taking corticosteroids and, when appropriate, should consider the use of objective neurocognitive tests or neuropsychology consultation to better characterize its presence and severity.

Corticosteroid therapy for hearing and balance disorders

This review addresses the current status of steroid therapies for hearing and vestibular disorders and how certain misconceptions may be undermining the efficacy in restoring normal ear function, both experimentally and clinically. Specific misconceptions addressed are that steroid therapy is not effective, steroid-responsive hearing loss proves an underlying inflammatory problem in the ear, and steroids only have application to the hearing disorders listed below. Glucocorticoid therapy for hearing and balance disorders has been employed for over 60 years. It is recommended in cases of sudden hearing loss, Meniére's disease, immune-mediated hearing loss, and any vestibular dysfunction suspected of having an inflammatory etiology. The predominant steroids employed today are dexamethasone, prednisone, prednisolone, and methylprednisolone. Despite years of use, little is known of the steroid responsive mechanisms in the ear that are influenced by glucocorticoid therapy. Furthermore, meta-analyses and clinical study reviews occasionally question whether steroids offer any benefit at all. Foremost in the minds of clinicians is the immune suppression and anti-inflammatory functions of steroids because of their efficacy for autoimmune hearing loss. However, glucocorticoids have a strong binding affinity for the mineralocorticoid (aldosterone) and glucocorticoid receptors, both of which are prominent in the ear. Because the auditory and vestibular end organs require tightly regulated endolymph and perilymph fluids, this ion homeostasis role of the mineralocorticoid receptor cannot be overlooked in both normal and pathologic functions of the ear. The function of the glucocorticoid receptor is to provide anti-inflammatory and antiapoptotic signals by mediating survival factors.