Neuronal activity and reward processing in relation to binge eating

PURPOSE OF REVIEW

Studies increasingly show the importance of reward processing in binge eating and provide evidence of associated changes in the neurobiological reward system. This review gives an up-to-date overview of the neurobiological substrates of reward processing subconstructs in binge eating. Neural findings are linked to different behavioral theories and the clinical relevance is discussed.

RECENT FINDINGS

Increased neural responses in the orbitofrontal cortex, anterior cingulate cortex as well as striatum during anticipation and receipt of food rewards are found in association to binge eating. Increased model-free learning is also found and associated with altered brain reward reactivity. Data in rest report reduced striatal dopamine release and lower frontostriatal connectivity. Mechanisms of onset of binge eating are less clear, but specific personality traits, related to frontostriatal dysconnectivity, probably increase the risk of binge eating onset.

SUMMARY

Both structural and task-based imaging studies show differences in the neurobiological reward system in binge eating. These changes are linked to specific reward processing, such as altered reward responsiveness to food cues, reinforcement learning, and habitual behavior. Findings are lined with different behavioral theories of binge eating, and a staging model is described, from onset to full illness development. Understanding the specific underlying aberrant reward mechanism in binge eating, associated with different stages of the illness, enables caregivers to focus their treatment more precisely.

The role of short-chain fatty acids (SCFAs) in regulating stress responses, eating behavior, and nutritional state in anorexia nervosa: protocol for a randomized controlled trial

OBJECTIVE

This protocol proposes investigating the effects of short-chain fatty acids (SCFAs)-namely acetate, propionate, and butyrate-as mediators of microbiota-gut-brain interactions on the acute stress response, eating behavior, and nutritional state in malnourished patients with anorexia nervosa (AN). SCFAs are produced by bacterial fermentation of dietary fiber in the gut and have recently been proposed as crucial mediators of the gut microbiota's effects on the host. Emerging evidence suggests that SCFAs impact human psychobiology through endocrine, neural, and immune pathways and may regulate stress responses and eating behavior.

METHOD

We will conduct a randomized, triple-blind, placebo-controlled trial in 92 patients with AN. Patients will receive either a placebo or a mixture of SCFAs (acetate propionate, butyrate) using pH-dependent colon-delivery capsules for six weeks. This clinical trial is an add-on to the standard inpatient psychotherapeutic program focusing on nutritional rehabilitation.

HYPOTHESES

We hypothesize that colonic SCFAs delivery will modulate neuroendocrine, cardiovascular, and subjective responses to an acute laboratory psychosocial stress task. As secondary outcome measures, we will assess alterations in restrictive eating behavior and nutritional status, as reflected by changes in body mass index. Additionally, we will explore changes in microbiota composition, gastrointestinal symptoms, eating disorder psychopathology, and related comorbidities.

DISCUSSION

The findings of this study would enhance our understanding of how gut microbiota-affiliated metabolites, particularly SCFAs, impact the stress response and eating behavior of individuals with AN. It has the potential to provide essential insights into the complex interplay between the gut, stress system, and eating behavior and facilitate new therapeutic targets for stress-related psychiatric disorders. This protocol is prospectively registered with ClinicalTrials.gov, with trial registration number NCT06064201.

How negative affect does and does not lead to binge eating-The importance of craving and negative urgency in bulimia nervosa

Studies suggest that negative affect (NA) can trigger binge eating (BE) in patients with bulimia nervosa (BN). Important factors in this relation between NA and BE could be craving (an intense desire for a BE episode) and negative urgency (the tendency to act rashly when NA is high). Therefore, this study wants to firstly explore the relations between NA, craving, rash action, and BE in daily life and secondly whether craving and rash action mediate the relationship between NA and BE. A sample of 70 female patients with BN and 76 female healthy controls (HC) took part in an experience sampling study where they reported on momentary NA, craving, rash action, and eating behaviors in daily life in a burst-measurement design over a period of 12 months. Assessments occurred eight times a day on Thursdays, Fridays, and Saturdays in seven bursts of 3 weeks, all separated by 5-week periods of no assessment. First, NA predicted subsequent rash action in the whole sample but this was more pronounced in patients with BN. Second, NA predicted subsequent craving in patients with BN, but not in HC. Third, rash action and craving predicted subsequent BE in patients with BN. Fourth, NA had competing effects on eating in patients with BN, predicting subsequent BE through rash action and craving, but also predicting subsequent not eating. These results suggest that NA can lead to BE in daily life through rash action and craving, but that NA can also lead to dietary restriction. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

['Slimmer's paralysis': peroneal neuropathy in anorexia nervosa]

We describe the development of slimmer’s paralysis or ‘foot drop’ in a patient with anorexia nervosa caused by a transient peroneal nerve injury. This was caused by extreme weight loss in combination with frequently crossing the legs in the context of anorexia nervosa with body image distortion. The most important interventions were weight recovery, physical therapy and avoiding precipitating factors. The relevance of this case lies in the fact that a physical complication of a predominantly mental illness is described. Moreover, this is a possibly lesser-known complication among psychiatrists. This case reminds clinical psychiatrists that mental illness can occur together with somatic complications. It is important to be aware of the possibility of this combination, in order to allow for early intervention and avoid additional injuries. This case also emphasizes the importance of multidisciplinary cooperation with respect to mental illness, in particular eating disorders.

[Lichaam en geest bij anorexia nervosa; een systematisch literatuuroverzicht]

BACKGROUND

Body image disturbance is a key component in anorexia nervosa (AN). In the treatment of AN this disturbed perception of the body poses a hindrance for clinical improvement and weight gain. Mindfulness and yoga are associated with a positive effect on the symptomatology of eating disorders.

AIM

We examined the therapeutical effect of mindfulness and yoga in the treatment of body image disturbances in AN patients.

METHOD

A systematic search in four medical databases using the concepts: ‘anorexia nervosa’, ‘consciousness-based therapy’ and ‘body image’. Results were included in a qualitative analysis.

RESULTS

10 studies were included in our analysis of which 3 dealt with mindfulness, 6 with yoga and 1 discussed a mixed program of both interventions.

CONCLUSION

We revealed a favourable effect of mindfulness and yoga on the symptoms of eating disorders among which AN. We also saw both quantitative and qualitative improvements of body image disturbance through general and specific measuring instruments. After the interventions the preoccupation and dissatisfaction with the body diminished together with the urge to lose weight. The heightened bodily awareness gave patients the ability to challenge negative assumptions about their bodies and resulted in increased bodily acceptation.

The neurobiological reward system and binge eating: A critical systematic review of neuroimaging studies

OBJECTIVE

Changes in reward processing are hypothesized to play a role in the onset and maintenance of binge eating (BE). However, despite an increasing number of studies investigating the neurobiological reward system in individuals who binge eat, no comprehensive systematic review exists on this topic. Therefore, this review has the following objectives: (1) identify structural and functional changes in the brain reward system, either during rest or while performing a task; and (2) formulate directions for future research.

METHODS

A search was conducted of articles published until March 31, 2022. Neuroimaging studies were eligible if they wanted to study the reward system and included a group of individuals who binge eat together with a comparator group. Their results were summarized in a narrative synthesis.

RESULTS

A total of 58 articles were included. At rest, individuals who binge eat displayed a lower striatal dopamine release, a change in the volume of the striatum, frontal cortex, and insula, as well as a lower frontostriatal connectivity. While performing a task, there was a higher activity of the brain reward system when anticipating or receiving food, more model-free reinforcement learning, and more habitual behavior. Most studies only included one patient group, used general reward-related measures, and did not evaluate the impact of comorbidities, illness duration, race, or sex.

DISCUSSION

Confirming previous hypotheses, this review finds structural and functional changes in the neurobiological reward system in BE. Future studies should compare disorders, use measures that are specific to BE, and investigate the impact of confounding factors.

PUBLIC SIGNIFICANCE STATEMENT

This systematic review finds that individuals who binge eat display structural and functional changes in the brain reward system. These changes could be related to a higher sensitivity to food, relying more on previous experiences when making decisions, and more habitual behavior. Future studies should use a task that is specific to binge eating, look across different patient groups, and investigate the impact of comorbidities, illness duration, race, and sex.

Regulation of CD4+ and CD8+ T Cell Biology by Short-Chain Fatty Acids and Its Relevance for Autoimmune Pathology

The gut microbiota encodes a broad range of enzymes capable of synthetizing various metabolites, some of which are still uncharacterized. One well-known class of microbiota-derived metabolites are the short-chain fatty acids (SCFAs) such as acetate, propionate, butyrate and valerate. SCFAs have long been considered a mere waste product of bacterial metabolism. Novel results have challenged this long-held dogma, revealing a central role for microbe-derived SCFAs in gut microbiota-host interaction. SCFAs are bacterial signaling molecules that act directly on host T lymphocytes by reprogramming their metabolic activity and epigenetic status. They have an essential biological role in promoting differentiation of (intestinal) regulatory T cells and in production of the anti-inflammatory cytokine interleukin-10 (IL-10). These small molecules can also reach the circulation and modulate immune cell function in remote tissues. In experimental models of autoimmune and inflammatory diseases, such as inflammatory bowel disease, multiple sclerosis or diabetes, a strong therapeutic potential of SCFAs through the modulation of effector T cell function was observed. In this review, we discuss current research activities toward understanding a relevance of microbial SCFA for treating autoimmune and inflammatory pathologies from in vitro to human studies.

The transition from restrictive anorexia nervosa to binging and purging: a systematic review and meta-analysis

Numerous studies addressed the topic of behavioral and symptomatic changes in eating disorders. Rates of transition vary widely across studies, ranging from 0 to 70.8%, depending on the diagnoses taken into account and the study design. Evidence shows that the specific transition from restrictive-type anorexia nervosa (AN-R) to disorders involving binging and purging behaviors (BPB) is related to a worsening of the clinical picture and worse long-term outcomes. The aim of this systematic review and meta-analysis is to focus on this specific transition, review existing literature, and summarize related risk factors. Medline and PsycINFO databases were searched, including prospective and retrospective studies on individuals with AN-R. The primary outcome considered was the rate of onset of BPB. Twelve studies (N = 725 patients) were included in the qualitative and quantitative analysis. A total of 41.84% (95% CI 33.58-50.11) of patients with AN-R manifested BPB at some point during follow-up. Risk factors for the onset of BPB included potentially treatable and untreatable factors such as the family environment, unipolar depression and higher premorbid BMI. These findings highlight that patients with AN-R frequently transition to BPB over time, with a worsening of the clinical picture. Existing studies in this field are still insufficient and heterogeneous, and further research is needed. Mental health professionals should be aware of the frequent onset of BPB in AN-R and its risk factors and take this information into account in the treatment of AN-R. LEVEL OF EVIDENCE: Evidence obtained from a systematic review and meta-analysis, Level I.

The impact of COVID-19-related smell and taste disorders on a patient with bulimia nervosa: a case report

A large number of patients with COVID-19 will suffer from long-term smell and taste disorders (STD). These STD symptoms could have a significant impact on patients with an eating disorder (ED). To highlight this issue, a case is presented of a patient with bulimia nervosa who experienced COVID-19-relate STD symptoms. Clinicians should reassess patients with an ED who suffer from COVID-19 with STD symptomatology and potentially redirect treatment. More research is needed on STD symptoms in patients with an ED to improve our knowledge on the role of smell and taste in disordered eating behaviors and improve treatment guidelines.

Exhausted Heart Rate Responses to Repeated Psychological Stress in Women With Major Depressive Disorder

Past research links depression and blunted cardiac vagal reactivity to chronic stress. Yet, to our knowledge no experiment investigates heart rate (variability) responses to a repeated laboratory stressor in patients with depression. Repeated exposure may provide valuable information on stress reactivity in depression. Fifty-nine women (30 inpatients diagnosed with depression and 29 matched controls) underwent two consecutive runs of a mental arithmetic stress paradigm consisting of one baseline and two exposures to control, stress, and recovery phases of 5 min each, in a case-control design. Subjective stress and electrocardiography were recorded. Variance of heart rate (HR) and root mean square of successive RR interval differences (RMSSD) were analyzed using linear mixed models. Overall, physiological parameters (HR and RMSSD) and subjective stress showed a strong group effect (all p < 0.001). In both groups, subjective stress and HR increased in response to stress, but the subjective stress levels of patients with depression did not return to baseline levels after the first stressor and for the remainder of the experiment (all p < 0.004 compared to baseline). Patients' HR reactivity responded oppositely: while HR recovered after the first stress exposure, no reactivity was observed in response to the second exposure. These findings may suggest that the often-reported blunted HR/HRV response to stressors results from exhaustion rather than an incapacity to react to stress. The altered HR reactivity could indicate allostatic (over-) load in depression.

[Diabetes mellitus and eating disorders: modified treatment is necessary]

The combination of an eating disorder and diabetes mellitus type 1 is a serious double diagnosis. Compensation behavior is often present in the form of insulin restriction which can have debilitating health consequences. Studies on prevalence, diagnosis and mortality are well documented but literature regarding evidence-based treatments is limited. In this article we describe a case study of a patient with diabetes who was admitted to our treatment unit for eating disorders due to manipulation of her diabetes medication. On the basis of this case and a literature study, we conclude that the standard treatment for eating disorders is insufficient for this double diagnosis. An adapted treatment, aimed at both the eating disorder and the diabetes is necessary to increase the chance of recovery.

The cumulative effect of chronic stress and depressive symptoms affects heart rate in a working population

BACKGROUND

Chronic stress and depressive symptoms have both been linked to increased heart rate (HR) and reduced HR variability. However, up to date, it is not clear whether chronic stress, the mechanisms intrinsic to depression or a combination of both cause these alterations. Subclinical cases may help to answer these questions. In a healthy working population, we aimed to investigate whether the effect of chronic stress on HR circadian rhythm depends on the presence of depressive symptoms and whether chronic stress and depressive symptoms have differential effects on HR reactivity to an acute stressor.

METHODS

1,002 individuals of the SWEET study completed baseline questionnaires, including psychological information, and 5 days of electrocardiogram (ECG) measurements. Complete datasets were available for 516 individuals. In addition, a subset (n = 194) of these participants completed a stress task on a mobile device. Participants were grouped according to their scores for the Depression Anxiety Stress Scale (DASS) and Perceived Stress Scale (PSS). We explored the resulting groups for differences in HR circadian rhythm and stress reactivity using linear mixed effect models. Additionally, we explored the effect of stress and depressive symptoms on night-time HR variability [root mean square of successive differences (RMSSD)].

RESULTS

High and extreme stress alone did not alter HR circadian rhythm, apart from a limited increase in basal HR. Yet, if depressive symptoms were present, extreme chronic stress levels did lead to a blunted circadian rhythm and a lower basal HR. Furthermore, blunted stress reactivity was associated with depressive symptoms, but not chronic stress. Night-time RMSSD data was not influenced by chronic stress, depressive symptoms or their interaction.

CONCLUSION

The combination of stress and depressive symptoms, but not chronic stress by itself leads to a blunted HR circadian rhythm. Furthermore, blunted HR reactivity is associated with depressive symptoms and not chronic stress.

Monocyte mitochondrial dysfunction, inflammaging, and inflammatory pyroptosis in major depression

BACKGROUND

The macrophage theory of depression states that macrophages play an important role in Major Depressive Disorder (MDD).

METHODS

MDD patients (N = 140) and healthy controls (N = 120) participated in a cross-sectional study investigating the expression of apoptosis/growth and lipid/cholesterol pathway genes (BAX, BCL10, EGR1, EGR2, HB-EGF, NR1H3, ABCA1, ABCG1, MVK, CD163, HMOX1) in monocytes (macrophage/microglia precursors). Gene expressions were correlated to a set of previously determined and reported inflammation-regulating genes and analyzed with respect to various clinical parameters.

RESULTS

MDD monocytes showed an overexpression of the apoptosis/growth/cholesterol and the TNF genes forming an inter-correlating gene cluster (cluster 3) separate from the previously described inflammation-related gene clusters (containing IL1 and IL6). While upregulation of monocyte gene cluster 3 was a hallmark of monocytes of all MDD patients, upregulation of the inflammation-related clusters was confirmed to be found only in the monocytes of patients with childhood adversity. The latter group also showed a downregulation of the cholesterol metabolism gene MVK, which is known to play an important role in trained immunity and proneness to inflammation.

CONCLUSIONS

The upregulation of cluster 3 genes in monocytes of all MDD patients suggests a premature aging of the cells, i.e. mitochondrial apoptotic dysfunction and TNF "inflammaging", as a general feature of MDD. The overexpression of the IL-1/IL-6 containing inflammation clusters and the downregulation of MVK in monocytes of patients with childhood adversity indicates a shift in this condition to a more severe inflammation form (pyroptosis) of the cells, additional to the signs of premature aging and inflammaging.

Interplay of Val66Met and BDNF methylation: effect on reward learning and cognitive performance in major depression

Background

There is a growing interest in the role of brain-derived neurotrophic factor (BDNF) in major depressive disorder (MDD). BDNF potentially exhibits opposite effects in the pathways linked to anhedonia and reward learning on the one hand and cognitive performance, on the other hand. However, the epigenetic mechanisms behind this remain unknown. In the present study, we aimed to investigate the interplay of DNA methylation of different BDNF exons and the common Val66Met polymorphism on anhedonia, reward learning and cognitive performance in MDD.

Methods

We recruited 80 depressed patients and 58 age- and gender-matched healthy controls. Participants underwent clinical assessment including neuropsychological testing and a probabilistic reward task to assess reward learning. Val66Met polymorphism and DNA methylation of BDNF promoters I, IV and exon IX were assessed from whole blood derived DNA, using pyrosequencing.

Results

BDNF promoter I methylation was lower in MDD patients (p = 0.042) and was negatively associated with self-reported anhedonia. In depressed patients, both Val66Met polymorphism and DNA methylation of promoter I were significantly associated with reward bias (p < 0.050 and p = 0.040, respectively), without an interaction effect. On the other hand, methylation of exon IX had a negative impact on executive functioning (p = 0.002) and mediated the effect of Val66Met on this outcome in patients with MDD.

Conclusions

Our results provide the first evidence of Val66Met susceptibility to differential epigenetic regulation of BDNF exons in reward learning and executive functioning in MDD, which needs to be further explored.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13148-021-01136-z.

Twenty-Four-Hour Heart Rate Is a Trait but Not State Marker for Depression in a Pilot Randomized Controlled Trial With a Single Infusion of Ketamine

Background: Abnormalities of heart rate (HR) and its variability are characteristic of major depressive disorder (MDD). However, circadian rhythm is rarely taken into account when statistically exploring state or trait markers for depression. Methods: A 4-day electrocardiogram was recorded for 16 treatment-resistant patients with MDD and 16 age- and sex-matched controls before, and for the patient group only, after a single treatment with the rapid-acting antidepressant ketamine or placebo (clinical trial registration available on https://www.clinicaltrialsregister.eu/ with EUDRACT number 2016-001715-21). Circadian rhythm differences of HR and the root mean square of successive differences (RMSSD) were compared between groups and were explored for classification purposes. Baseline HR/RMSSD were tested as predictors for treatment response, and physiological measures were assessed as state markers. Results: Patients showed higher HR and lower RMSSD alongside marked reductions in HR amplitude and RMSSD variation throughout the day. Excellent classification accuracy was achieved using HR during the night, particularly between 2 and 3 a.m. (90.6%). A positive association between baseline HR and treatment response (r = 0.55, p = 0.046) pointed toward better treatment outcome in patients with higher HR. Heart rate also decreased significantly following treatment but was not associated with improved mood after a single infusion of ketamine. Limitations: Our study had a limited sample size, and patients were treated with concomitant antidepressant medication. Conclusion: Patients with depression show a markedly reduced amplitude for HR and dysregulated RMSSD fluctuation. Higher HR and lower RMSSD in depression remain intact throughout a 24-h day, with the highest classification accuracy during the night. Baseline HR levels show potential for treatment response prediction but did not show potential as state markers in this study. Clinical trial registration: EUDRACT number 2016-001715-21.

How COVID-19 lockdown measures could impact patients with bulimia nervosa: Exploratory results from an ongoing experience sampling method study

Introduction

Preliminary results indicate that COVID-19 lockdown measures could lead to an increase in eating disorder pathology. However, some patients could be more vulnerable to experience such an increase than others. The reason why some patients are more susceptible to the impact of lockdown measures is still not known.

Objectives

To analyze the impact of the Belgian COVID-19 lockdown measures on the surroundings, social context, negative affect (NA), positive affect (PA) and binge eating frequency of patients with bulimia nervosa (BN).

Methods

The data of 15 female patients with BN from an ongoing experience sampling method study were analyzed. Mixed effects models compared surroundings, social context, NA, PA and binge eating before and after the implementation of the lockdown measures.

Results

After the implementation of the lockdown measures, significant changes in surroundings and social context were found as well as an increase in NA (p < 0.001) and decrease in PA (p = 0.015). Patients who experienced an increase in binge eating frequency also experienced a stronger increase in NA (p = 0.012) and decrease in PA (p = 0.026) after the lockdown measures were implemented.

Conclusions

Future research should also look at changes in surroundings, social context, affect and how these interact with factors such as personality traits and coping styles when investigating why some patients are more susceptible to the negative effects of lockdown measures than others.

How COVID-19 lockdown measures could impact patients with bulimia nervosa: Exploratory results from an ongoing experience sampling method study

OBJECTIVE

The impact of COVID-19 lockdown measures on patients with an eating disorder remains unclear, but preliminary results indicate that some patients could be more vulnerable to experience an increase in eating disorder pathology than others. To provide possible directions for future research, this report explored the impact of the Belgian COVID-19 lockdown measures on patients with bulimia nervosa (BN).

METHODS

The data of 15 female patients with BN from an ongoing experience sampling method study were analyzed. Mixed effects models compared surroundings, social context, negative affect (NA), positive affect (PA) and binge eating before and after the implementation of the lockdown measures.

RESULTS

After the implementation of the lockdown measures, significant changes in surroundings and social context were found as well as an increase in NA and decrease in PA. Patients who experienced a higher binge eating frequency during the lockdown also experienced a stronger change in NA and PA.

CONCLUSIONS

Future research should also look at changes in surroundings, social context, affect and how these interact with factors such as personality traits and coping styles when investigating why some patients are more susceptible to the negative effects of lockdown measures than others.

Sociodemographic and clinical characteristics of eating disorder patients treated in the specialized residential settings in Belgium

INTRODUCTION

Epidemiologic information on sociodemographic and clinical characteristics in eating disorders in Western European countries are scarce.

PURPOSE

In this study, we report demographic and clinical characteristics of eating disorder (ED) patients undergoing treatment in five specialized ED centers in Flanders (Belgium).

METHOD

Data from 642 ED patients were collected by means of a structured questionnaire.

RESULTS

Data show that 93.8% of patients are female, with an average age of 22.6 years. The largest subgroup in our sample suffers from anorexia nervosa, namely 52.8%. Bulimia nervosa (BN), binge eating disorder (BED) and eating disorder not otherwise specified (EDNOS) account for 17.7%, 10.7% and 18.8% of the sample, respectively. Mean age of onset was 17 years. Mean duration of illness was 5.6 years, but 20.2% of patients had their illness for over 8 years. Anorexia nervosa patients of the restricting type (AN-R) have the shortest duration of illness. BED patients stood out because they were older on average, more often in a relationship and more often in ambulatory treatment. 70% of patients over 20 years old completed higher education, but one-third of this group was unemployed and/or disabled. Remarkably, ED patients grow more up in intact families compared to the general population.

CONCLUSIONS

Epidemiology of ED patients in treatment in Flanders (Belgium) seems to resemble worldwide findings. The long duration of illness, the common evolution towards chronicity and the early work impairment underline the severe personal and societal impact of ED and call to the need for early detection and treatment of these patients.

LEVEL OF EVIDENCE

Level V: cross-sectional descriptive study.

Investigating the stress-related fluctuations of level of personality functioning: A critical review and agenda for future research

The Diagnostic and Statistical Manual of Mental Disorders (DSM-5) and the International Classification of Diseases (ICD-11) proposed a dimensional approach to the assessment of personality disorders (PDs). Both models dictate that the clinician first determines PD severity before assessing maladaptive traits, invoking the level of personality functioning (LPF) construct. We consider LPF a promising dimensional construct for translational research because of its clinical importance and conceptual overlap with the Research Domain Criteria (RDoC) Social Processes. We aim to identify biomarkers that co-vary with fluctuations in LPF in adulthood, ultimately to predict persistent decrease in LPF, associated with suicidality and morbidity. However, a theoretical framework to investigate stress-related oscillations in LPF is currently missing. In this article, we aim to fill this hiatus with a critical review about stress and LPF. First, we discuss acute stress and LPF. We briefly present the basics of the neurophysiological stress response and review the literature on momentary and daily fluctuations in LPF, both at a subjective and physiological level. Second, we review the effects of chronic stress on brain function and social behaviour and recapitulate the main findings from prospective cohort studies. This review underlies our suggestions for multimethod assessment of stress-related oscillations in LPF and our theoretical framework for future longitudinal studies, in particular studies using the experience sampling method (ESM).

[Conversion and dissociation: together or separated?]

BACKGROUND

Conversion and dissociation in their relationship have made a lot of pendulum movements over time between moving together and away from each other. In the run-up to the introduction of DSM-5, it was argued that conversion should be classified as a dissociative disorder, but this didn't happen.

AIM

In this article, the clinical scientific evidence is examined for the relationship between conversion and dissociation. We provide an overview of the recent clinical studies that examine both syndromes together. We also investigate the main overlapping predisposing characteristics and psychopathological explanatory models of both syndromes.

METHOD

Literature review in PubMed and PsycArticles.

RESULTS

Our findings confirm that there is a large comorbidity between conversive and dissociative symptoms in clinical reality. Both syndromes have a high prevalence of reported trauma and emotion dysregulation. However, evidence for present biomarkers is still llimited. The underlying explanation models are applicable for both conversion and dissociation.

CONCLUSION

We want to draw attention to the plea to bring conversion disorders back together with dissociative disorders. Moreover, the possible presence of trauma, the influential role of psychosocial stressors, the present psychiatric co-morbidity and the style of emotion regulation seem to justify the approach to conversion problems from a biopsychosocial perspective rather than from a purely biomedical perspective.

[Electroconvulsive therapy in the treatment of depression in anorexia nervosa]

BACKGROUND

Often anorexia nervosa occurs with other psychiatric comorbidities of which mood disorders are the most frequent. Depressive feelings hamper the chance of a favourable outcome of this persistent disorder. In addition, the underweight makes antidepressants work suboptimal. Electroconvulsive therapy (ECT) offers an important therapeutic value in the treatment of mood disorders. We are investigating whether ECT can be an effective treatment method for patients with anorexia nervosa and major depressive disorder.

AIM

Analysis of the literature on the possible effectiveness of electroconvulsive therapy (ECT) in the treatment of major depressive disorder and anorexia nervosa supplemented with a case report.

METHOD

Literature study in PubMed, Web of Science and Embase and a case report.

RESULTS

262 published articles were found between 1955 and 2020, 16 were found to be relevant.

CONCLUSION

From the literature, clinical recommendations cannot be made binding. No randomized controlled trials have been published on this subject. However, we saw in our case study and in the literature found that clearing the depressive symptoms through electroconvulsive therapy led to an improvement in food and fluid intake. ECT has no effect on their deranged thought pattern.

Increased methylation of NR3C1 and SLC6A4 is associated with blunted cortisol reactivity to stress in major depression

Background

Epigenetic changes are considered the main mechanisms behind the interplay of environment and genetic susceptibility in major depressive disorder (MDD). However, studies focusing on epigenetic dysregulation of the HPA axis stress response in MDD are lacking. Our objective was to simultaneously asses DNA methylation of the glucocorticoid receptor gene (NR3C1) and serotonin transporter gene (SLC6A4) and HPA axis response to stress in MDD.

Methods

We recruited 80 depressed inpatients and 58 gender and age matched healthy controls. All participants underwent the Trier Social Stress Test (TSST) and salivary cortisol was repeatedly measured to assess HPA axis reactivity. DNA methylation of the NR3C1 (exon 1 F) and SLC6A4 CpG islands was quantified from whole blood DNA. In the MDD group, clinical assessment was repeated at 8-week follow-up to test the predictive potential of DNA methylation for symptom improvement.

Results

Depressed patients had blunted cortisol reactivity to TSST compared to healthy controls (p = 0.01). In addition, they presented with increased average SLC6A4 (p = 0.003) and NR3C1 methylation (p = 0.03), as well as methylation of two individual NR3C1 CpG loci overlapping with the NGFI-A-binding sites (CpG12 and CpG20). Methylation of one of these two loci (CpG20) predicted lower symptom improvement at the follow-up (p = 0.007). Both, average NR3C1 and SLC6A4 methylation were associated with lower cortisol reactivity in the MDD group and explained about 16% of variability in cortisol response to TSST.

Conclusions

We provide evidence of the role of NR3C1 and SLC6A4 DNA methylation in HPA axis dysregulation in MDD, which needs to be further explored.

Depression and suicidality: A link to premature T helper cell aging and increased Th17 cells

BACKGROUND

Previous research has demonstrated a strong link between immune system abnormalities and Major Depressive Disorder (MDD). High suicide risk is a major complication of MDD and has recently been linked to strong (neuro-)immune alterations, but little is known on the link between circulating immune cell composition and suicidal risk status.

METHODS

Here, we assessed percentages of circulating peripheral blood mononuclear cells with focus on T helper cell subsets (memory T helper cells, Th1, Th2, Th17 and T regulatory cells) in a large and well-matched cohort of 153 patients diagnosed with MDD and 153 age and sex matched controls. We explored the association of these cell populations with suicide risk while accounting for age, sex, BMI, depression severity and childhood trauma.

RESULTS

Patients with MDD had reduced percentages of NK cells, and higher percentages of B and T cells in line with current literature. Further exploration of T-cells revealed a robustly elevated number of memory T helper cells, regardless of age group. Patients at high risk for suicide had the highest memory T helper cells and additionally showed a robust increase of Th17 cells compared to other suicide risk groups.

CONCLUSIONS

The higher abundance of memory T helper cells points towards premature aging of the immune system in MDD patients, even during young adulthood. Patients at high risk for suicide show the clearest immune abnormalities and may represent a clinically relevant subtype of depression.

Binge eating and purging in first-year college students: Prevalence, psychiatric comorbidity, and academic performance

BACKGROUND

Binge eating and purging behaviors (BPB) are common among college students, but evidence is scant on prevalence and associations of BPB with mental health problems and objective academic performance. This study aims to investigate: (a) 12-month prevalence of BPB among college first-year students, (b) comorbidity patterns of BPB with various mental health problems, and (c) the association of BPB with objective academic functioning.

METHODS

Using data from the Leuven College Surveys (Belgium), as part of the World Mental Health Surveys International College Student initiative, we cross-sectionally assessed 12-month BPB and mental health problems among college first-year students (n = 4,889; response rate = 73.2%) at the beginning of the academic year. Objective measures of academic functioning (final grades, expressed in academic year percentage "AYP" [0-100%] and academic failure) were obtained from administrative records at the end of the academic year.

RESULTS

Twelve-month prevalence of BPB was 7.6% (7.3%binge eating and 1.0%purging), with higher rates among females than males. Bivariate models showed an association between BPB and numerous mental health problems (ORs = 3.4-18.4). Multivariate models showed associations with non-suicidal self-injury, post-traumatic stress, internalizing/externalizing problems and suicidal ideation. After controlling for sociodemographic characteristics and comorbid mental health problems, BPB were still associated with lower AYP (-4.1 to -11.2% range) and elevated odds of academic year failure (ORs = 1.4-4.2).

CONCLUSIONS

BPB (especially binge eating) are relatively common and associated with mental health problems, comparatively low academic performance, and higher risk of academic failure among college first-year students. Further study is needed to examine the causal dynamics underlying these associations.

The effect of trauma and dissociation on the outcome of cognitive behavioural therapy for binge eating disorder: A 6-month prospective study

BACKGROUND

Binge eating disorder (BED) is commonly associated with a history of trauma. Yet, there is little insight into the potential effect that trauma, dissociation, and depressive symptoms may have on the outcome of treatment interventions.

METHODS

A total of 142 treatment-seeking patients admitted with a diagnosis of DSM-5 BED (88% female; mean age = 38.7; SD = 10.8) took part in a 6-month, protocolized, group cognitive behavioural therapy (CBT). Self-report questionnaires were administered to assess lifetime traumatic experiences, dissociation, and depression. Body mass index and the number of binges per week (BPW) were measured throughout treatment. The main outcomes were the percentage reduction in BPW and remission (i.e., less than one BPW; cf. DSM-5).

RESULTS

Most BED patients (91.5%) reported a history of trauma, with two in three patients reporting three or more traumatic experiences. Whereas the number of traumatic experiences was not significantly associated with a reduction in BPW or remission, a higher traumatic impact score significantly decreased the likelihood of obtaining remission at the end of treatment (OR = 0.96; 95% CI [0.92, 0.99]). Higher levels of dissociative symptoms partially mediated this prospective association.

CONCLUSIONS

The impact of traumatic experiences, as opposed to the number of traumatic experiences experienced, negatively predicts remission after 6 months of CBT. These findings highlight the importance of addressing trauma and dissociative features in the CBT treatment of BED.

[Clinical zoanthropy: a woman with the rare delusion of being an animal]

Clinical zoanthropy, or the conviction of having turned into an animal, is a rare delusion. There are different views about its pathogenesis. This delusion can occur with an underlying psychiatric disorder, but it can also be secondary to structural or functional disorders of the brain. Additional investigations with brain imaging and electroencephalogram are therefore advised. Treatment for the underlying disorder is recommended. In this case report we describe a 54-year-old woman who was briefly convinced she was a chicken, followed by a generalized seizure. We discuss the epidemiology, theories about pathogenesis and treatment advice for clinical zoanthropy. We also discuss the possible relevance of epilepsy to this matter. With this case report, we hope to contribute to documenting this rare, but possibly underreported phenomenon.

Ambulatory Smoking Habits Investigation based on Physiology and Context (ASSIST) using wearable sensors and mobile phones: protocol for an observational study

INTRODUCTION

Smoking prevalence continues to be high over the world and smoking-induced diseases impose a heavy burden on the medical care system. As believed by many researchers, a promising way to promote healthcare and well-being at low cost for the large vulnerable smoking population is through eHealth solutions by providing self-help information about smoking cessation. But in the absence of first-hand knowledge about smoking habits in daily life settings, systems built on these methods often fail to deliver proactive and tailored interventions for different users and situations over time, thus resulting in low efficacy. To fill the gap, an observational study has been developed on the theme of objective and non-biased monitoring of smoking habits in a longitudinal and ambulatory mode. This paper presents the study protocol. The primary objective of the study is to reveal the contextual and physiological pattern of different smoking behaviours using wearable sensors and mobile phones. The secondary objectives are to (1) analyse cue factors and contextual situations of smoking events; (2) describe smoking types with regard to users' characteristics and (3) compare smoking types between and within subjects.

METHODS AND ANALYSES

This is an observational study aimed at reaching 100 participants. Inclusion criteria are adults aged between 18 and 65 years, current smoker and office worker. The primary outcome is a collection of a diverse and inclusive data set representing the daily smoking habits of the general smoking population from similar social context. Data analysation will revolve around our primary and secondary objectives. First, linear regression and linear mixed model will be used to estimate whether a factor or pattern have consistent (p value<0.05) correlation with smoking. Furthermore, multivariate multilevel analysis will be used to examine the influence of smokers' characteristics (sex, age, education, socioeconomic status, nicotine dependence, attitudes towards smoking, quit attempts, etc), contextual factors, and physical and emotional statuses on their smoking habits. Most recent machine learning techniques will also be explored to combine heterogeneous data for classification of smoking events and prediction of craving.

ETHICS AND DISSEMINATION

The study was designed together by an interdisciplinary group of researchers, including psychologist, psychiatrist, engineer and user involvement coordinator. The protocol was reviewed and approved by the ethical review board of UZ Leuven on 18 April 2016, with an approval number S60078. The study will allow us to characterise the types of smokers and triggering events. These findings will be disseminated through peer-reviewed articles.

Toward Quantifying the Psychopathology of Eating Disorders From the Autonomic Nervous System Perspective: A Methodological Approach

The phenomenology of Eating Disorders (ED) relates with altered functioning of the Autonomic Nervous System (ANS). The lack of agreement in what comes to the direction and significance of such alterations is possibly due to the variability in the ED spectrum. As the stress response system is an integral part of the ANS, we propose to investigate ANS tonic variations and phasic activations in response to stressors. We hypothesize that, while using stress as a test probe, characteristic ANS dysregulations in ED may be found when considering several physiological signals measured over time, and weighted by the individual psychological profiles. In this article we describe a novel methodological approach to investigate this hypothesis with the aim of providing further clarification on the ED spectrum conceptualization. The proposed methodology has been designed to be easily integrated in clinical practice and, eventually, in daily life. The population under observation includes both patients in treatment for ED, and matched controls. The study session has the duration of 1 day, including: (1) the administration of a stress task in a controlled environment and (2) naturalistic data collection. The stress task is designed to elicit both mentally and physically driven ANS activation. The naturalistic component intends to illustrate the psychophysiology in everyday life. We use wearable devices to continuously and non-invasively measure bio-signals related to ANS functioning. This information is complemented with psychometric information from validated stress and ED scales and ecological momentary assessments. The protocol has received ethical approval and has been implemented in practice, currently accounting for 37 patients (out of 120) and 16 controls (out of 60). Ongoing work focus on the definition and implementation of a data processing pipeline to quantitatively test our hypothesis, both standard statistical methods and more exploratory machine learning approaches will be considered.

Characteristics and content of intrusive images in patients with eating disorders

The aim of this study was to examine the characteristics and content of intrusive images in patients with different subtypes of eating disorders (EDs). Data were collected from 74 ED patients, 22 dieting, and 29 nondieting controls. Participants completed a set of self-report questionnaires. Intrusive images of ED patients were significantly more repetitive, detailed, vivid, and distressing than intrusive images of dieting and/or nondieting controls. Most of the intrusive images were the same for the ED subtypes; however, patients with anorexia nervosa were more likely to report an observer vantage perspective than patients with bulimia nervosa, who were more likely to report a field vantage perspective. As expected, intrusive images' content was related to body checking (weight and shape) or negative self (evaluated by themselves or others). Finally, there were significant associations between intrusive images' vividness and weight and shape concerns. These findings indicate that intrusive images may be a core element of EDs and targeting intrusive images in therapy may be helpful.

Heart rate and high frequency heart rate variability during stress as biomarker for clinical depression. A systematic review

The interaction of physical and mental vulnerability and environmental constraints is thought to foster the development of psychiatric disorders such as major depressive disorder (MDD). A central factor in the development of psychopathology is mental stress. Despite some evidence for parasympathetic withdrawal and sympathetic overactivity in MDD, the psychophysiological response to stress in depression is not clear-cut. Given the growing interest in heart rate and heart rate variability as indicators for remote monitoring of patients, it is important to understand how patients with MDD react to stress in a laboratory-controlled environment. We conducted a systematic review of studies using electrocardiography to derive heart rate and heart rate variability during stress in patients with clinical depression. We focused on well-validated stress tasks- the mental arithmetic stress task, the Trier social stress task and public speaking task- to minimize confounding effects due to the nature of the stressor. The majority of studies found hypo-reactivity during stress as a hallmark of depression as evidenced by lower fluctuation in heart rate and heart rate variability in the high-frequency band. We address the potential underlying biological mechanisms, the influence of covariates on these measures and briefly discuss the specificity and potential for remote monitoring by using these variables.

[Sexuality in eating-disorder patients]

BACKGROUND

A link is suspected between eating disorders and dysfunctional sexuality. The grounds for this link are thought to be clinical, biological and psychological.

AIM

To find out from the literature what is known about sexuality in patients with eating disorders, to identify differences related to subtypes of the disorders and to ascertain whether sexuality can play a role in the diagnosis and treatment of various types of eating disorders.

METHOD

We studied the research literature with the help of PubMed.

RESULTS

Patients with eating disorders are more likely to have sexual problems; these include reduced libido, reduced sexual activity and sexual dissatisfaction. The distorted body image leads to the avoidance of sexual activity. Anorexia patients are more negative about sexuality and have a greater loss of libido than do bulimia patients, who experiment more with sex.

CONCLUSION

Patients with eating disorders experience sexual dysfunction, but there are clear differences between the various eating-disorder subtypes. It is advisable that, in the future, sexuality should be included in the outcome of research in eating disorders. This step will help researchers to evaluate the effect that treatment can have on the outcome of the eating disorder.

Reduced reward learning predicts outcome in major depressive disorder

BACKGROUND

Reduced reward learning might contribute to the onset and maintenance of major depressive disorder (MDD). In particular, the inability to utilize rewards to guide behavior is hypothesized to be associated with anhedonia, a core feature and potential trait marker of MDD. Few studies have investigated whether reduced reward learning normalizes with treatment and/or reward learning predicts clinical outcome. Our goal was to test whether MDD is characterized by reduced reward learning, especially in the presence of anhedonic symptoms, and to investigate the relationship between reward learning and MDD diagnosis after 8 weeks of treatment.

METHODS

Seventy-nine inpatients and 63 healthy control subjects performed a probabilistic reward task yielding an objective measure of participants' ability to modulate behavior as a function of reward. We compared reward responsiveness between depressed patients and control subjects, as well as high- versus low-anhedonic MDD patients. We also evaluated whether reward-learning deficits predicted persistence of MDD after 8 weeks of treatment.

RESULTS

Relative to control subjects, MDD patients showed reduced reward learning. Moreover, patients with high anhedonia showed diminished reward learning compared with patients with low anhedonia. Reduced reward learning at study entry increased the odds of a persisting diagnosis of MDD after 8 weeks of treatment (odds ratio 7.84).

CONCLUSIONS

Our findings indicate that depressed patients, especially those with anhedonic features, are characterized by an impaired ability to modulate behavior as a function of reward. Moreover, reduced reward learning increased the odds for the diagnosis of MDD to persist after 8 weeks of treatment.

Relationship between cognitive avoidant coping and changes in overgeneral autobiographical memory retrieval following an acute stressor

According to the functional avoidance hypothesis, overgeneral autobiographical memory, the tendency to retrieve personal memories in a less specific format, might serve an affect-regulating function. Reducing the specificity of memories of negative events may prevent individuals from re-experiencing the associated painful emotions. This cognitive avoidance strategy might not only be employed by depressed and traumatized patients, but also by healthy individuals. In the present study we tested the hypothesis that the increase in memory overgenerality induced by an acute stressor is positively correlated with habitual (cognitive) avoidant coping. Participants (N = 32) were exposed to a Trier Social Stress Test. Cognitive avoidant coping was measured at the start of the experiment by means of the Mainz Coping Inventory. Before, immediately after, and 40 min after the Trier Social Stress Test, autobiographical memory specificity was assessed by means of the Autobiographical Memory Test. Cognitive avoidant coping was significantly correlated with an increase in categoric memories from pre to immediately post stressor, but not with change in overgeneral memories from pre to 40 min post stressor. The results of the present experiment provide further support for functional avoidance as one of the mechanisms underlying overgeneral memory.

The influence of maternal cortisol and emotional state during pregnancy on fetal intrauterine growth

BACKGROUND

This exploratory study investigates the influence of maternal cortisol and emotional state during pregnancy on fetal intrauterine growth (IUG). We expected higher basal cortisol levels, or more depressive and anxious complaints during pregnancy, to be associated with slower IUG and lower birth weight.

METHODS

A total of 91 pregnant women were recruited from the antenatal clinic and were seen once each trimester. In addition to psychological assessments, a diurnal cortisol profile was derived from saliva samples. IUG was evaluated using ultrasound.

RESULTS

In mid-pregnancy (trimester (T)2), basal cortisol levels significantly predicted the variance of weight (proportion of variance in growth variable explained (PVE) = 11.6%) and body mass index (BMI) at birth (PVE = 6.8%). In late pregnancy (T3) emotional state, particularly depressive symptoms (BMI at birth: PVE = 6.9%; ponderal index (PI) at birth: PVE = 8.2%; head circumference at T3: PVE = 10.3%; head circumference at birth PVE = 9.1%) and attachment (BMI at birth: PVE = 6.9%; PI at birth: PVE = 7.2%) had an influence on growth. Analysis of growth between T2 and T3 showed that attachment and cortisol in T3 had an influence on the variation in increase in estimated fetal weight (PVE = 12.5-8.6%).

CONCLUSION

These data indicate basal cortisol levels were more important in T2 whereas emotional state was more important in T3.

Measuring extrastriatal dopamine release during a reward learning task

OBJECTIVES

Reward learning is critical for survival. Animal research emphasizes the role of dopaminergic (DA) mesocorticolimbic pathways in reward learning, but few studies have evaluated extrastriatal DA functioning in humans. The purpose of this study was to examine presynaptic DA release in extrastriatal regions of the reward circuit by measuring displacement of the high affinity D(2) /D(3) radioligand [(18) F]Fallypride during a reward task.

DESIGN

Ten healthy volunteers underwent a [(18) F]Fallypride positron emission tomography protocol while performing a reward task, allowing us to assess participants' ability to modulate behavior as a function of reward. DA receptor ligand displacement was correlated with task performance and self-reported anhedonia.

OBSERVATIONS

Parametric t-maps revealed significant decrease in [(18) F]Fallypride binding in the medial orbitofrontal cortex (mOFC), ventromedial prefrontal cortex (vmPFC), and dorsal anterior cingulate cortex (dACC), indicating endogenous DA release in these regions. Increasing anhedonic symptoms correlated with DA release in the left vmPFC, left dACC, and right dACC emerged (all r's > 0.65, P's < 0.05). Similarly, reduced reward learning correlated with higher DA release in left vmPFC, right vmPFC, and left dACC (all r's < -0.64, P's < 0.05). Left dACC (r = 0.66, P = 0.04) and left vmPFC (r = 0.74, P = 0.01) DA release showed a significant positive correlation with impaired tendency to modulate behavior as a function of prior positive reinforcements.

CONCLUSIONS

These findings support the hypothesis that DA release in mOFC, vmPFC, and dACC regions plays an important role in reinforcement learning in the human brain.

Reward Sensitivity and Response to Treatment in Major Depression

Rationale:

Anhedonia, or the lack of reactivity to a pleasurable stimuli is expressed as reduced reward sensitivity in patients with major depressive disorder (MDD) (1). Reward experience might discriminate between depressed patients who respons to treatment and those who do not (2).

Objective:

The purpose of this study was to test the hypothesis that patients non-responsive to treatment show reduced reward sensitivity compared to responsive patients.

Method:

A probabilistic computer task was used to measure reward sensitivity objectively (3). Twenty-eight medicated inpatients meeting DSM-IV criteria for MDD performed the reward task within the first week after submission and again after eight weeks. The response to treatment was assessed with the Hamilton Depression rating Scale (HDRS). Patients with scores less that ten or a fifty percent reduction on the HDRS after 8 weeks were considered responders to treatment. Sixteen healthy subjects were recruited as controls.

Results:

When considering reward sensitivity at baseline, the control group was significantly more sensitive to reward than the responders group and the non-responders group, who were the least reward sensitive (F = 11.88; p < 0.01). After 8 weeks, responders showed an almost similar reward dependence to controls on the task, however non-responders still preformed significantly worse compared to both responders and controls (F= 8.71; p< 0.01).

Conclusion:

These results support the hypothesis that impairment of reward responsiveness might influence response to treatment in patients with MDD.

[De Clérambault syndrome. A case report and a review of the literature on the difference between primary and secondary erotomania]

This case report is about a female patient with an erotomanic delusion, who is convinced that a man is deeply in love with her. Because the specific course of primary erotomania and its response to treatment have been documented, the literature was studied to find out whether it distinguishes between primary and secondary erotomania. The search, however, showed that erotomania occurs so rarely and is defined in such ambiguous terms that it is impossible to divide these subtypes into two separate entities.