Issues for DSM-V: should obesity be included as a brain disorder?

Efficacy of eHealth interventions to reduce depression symptoms in individuals with obesity: a systematic review of randomized controlled trials

Introduction

Obesity and depression are inter-related health concerns, demanding a high level of treatment and costs in the health care system. The development of eHealth interventions that simultaneously address obesity and mental health can be supportive in this regard. However, evidence of the efficacy of eHealth interventions in the treatment of depression symptoms in individuals with obesity is lacking. The aim of this systematic literature review is to evaluate the efficacy of existing eHealth interventions for individuals with obesity that target depression symptoms.

Methods

We systematically searched electronic databases (Cochrane Library, PubMed, Scopus) to identify studies published in English between January 2016 and January 2023, that focused on eHealth interventions, targeting depression symptoms in individuals with obesity people. Exclusion criteria were study objectives that (1) focused specifically on one or more metabolic comorbidities of individuals with obesity, e.g., hypertension, hyperlipidemia, diabetes; (2) focused specifically on eating disorders comorbidities e.g., binge eating disorder, and (3) focused specifically on patients before or after bariatric surgery.

Results

The database search identified 214 records. Six articles were included in this review. Sample sizes ranged from 70 to 1267 participants of ages 18-60 years. All included studies were randomized controlled trials. Two of the six included studies were web-based interventions guided either by medical doctors or psychologists. All interventions included video, printed materials, and interactive parts of which two studies integrated elements of Cognitive Behavioural Therapy and Social Cognitive Therapy. The findings showed that eHealth treatment services, supported and guided throughout the intervention had high acceptance and efficacy in the reduction of depression symptoms among individuals with obesity.

Conclusion

EHealth interventions that address and target both mental and physical health with interactive strategies calls for better efficacy in the reduction of depression symptoms. Future eHealth interventions that target depression symptoms in individuals with obesity should integrate digital strategies that address both mental and physical health through interactive modules.

Automatic diagnosis of schizophrenia and attention deficit hyperactivity disorder in rs-fMRI modality using convolutional autoencoder model and interval type-2 fuzzy regression

Nowadays, many people worldwide suffer from brain disorders, and their health is in danger. So far, numerous methods have been proposed for the diagnosis of Schizophrenia (SZ) and attention deficit hyperactivity disorder (ADHD), among which functional magnetic resonance imaging (fMRI) modalities are known as a popular method among physicians. This paper presents an SZ and ADHD intelligent detection method of resting-state fMRI (rs-fMRI) modality using a new deep learning method. The University of California Los Angeles dataset, which contains the rs-fMRI modalities of SZ and ADHD patients, has been used for experiments. The FMRIB software library toolbox first performed preprocessing on rs-fMRI data. Then, a convolutional Autoencoder model with the proposed number of layers is used to extract features from rs-fMRI data. In the classification step, a new fuzzy method called interval type-2 fuzzy regression (IT2FR) is introduced and then optimized by genetic algorithm, particle swarm optimization, and gray wolf optimization (GWO) techniques. Also, the results of IT2FR methods are compared with multilayer perceptron, k-nearest neighbors, support vector machine, random forest, and decision tree, and adaptive neuro-fuzzy inference system methods. The experiment results show that the IT2FR method with the GWO optimization algorithm has achieved satisfactory results compared to other classifier methods. Finally, the proposed classification technique was able to provide 72.71% accuracy.

Obesity-mediated Lipoinflammation Modulates Food Reward Responses

Accumulation of white adipose tissue (WAT) during obesity is associated with the development of chronic low-grade inflammation, a biological process known as lipoinflammation. Systemic and central lipoinflammation accumulates pro-inflammatory cytokines including IL-6, IL-1β and TNF-α in plasma and also in brain, disrupting neurometabolism and cognitive behavior. Obesity-mediated lipoinflammation has been reported in brain regions of the mesocorticolimbic reward circuit leading to alterations in the perception and consumption of ultra-processed foods. While still under investigation, lipoinflammation targets two major outcomes of the mesocorticolimbic circuit during food reward: perception and motivation ("Wanting") and the pleasurable feeling of feeding ("Liking"). This review will provide experimental and clinical evidence supporting the contribution of obesity- or overnutrition-related lipoinflammation affecting the mesocorticolimbic reward circuit and enhancing food reward responses. We will also address neuroanatomical targets of inflammatory profiles that modulate food reward responses during obesity and describe potential cellular and molecular mechanisms of overnutrition linked to addiction-like behavior favored by brain lipoinflammation.

Addiction-like behaviour towards high-fat high-sugar food predicts relapse propensity in both obesity prone and obesity resistant C57BL/6 J mice

Compulsive overeating of palatable food is thought to underlie some forms of obesity. Similarities are often observed in the behavioural symptomology and the neuropathophysiology underlying substance use disorder and compulsive overeating. As such, preclinical animal models which assess addiction-like behaviour towards food may assist the understanding of the neurobiology underlying overeating behaviour. Further, the relationship between these behaviours and the propensity for diet-induced obesity warrants examination. In this study we investigated the relationship between the propensity for diet-induced obesity (DIO) and addiction-like behaviour towards highly palatable food in C57BL/6 J mice as measured by a 3-criteria model. We also examined the extent to which performance on this 3-criteria model predicted two key hallmark features of addiction - resistance to extinction and relapse propensity (as measured by reinstatement of lever pressing). C57BL/6 J mice were allowed free access to a palatable diet for 8 weeks then separated by weight gain into DIO-prone and DIO-resistant subgroups. Access to palatable food was then restricted to daily operant self-administration sessions whereby addiction-like behaviour towards a high-fat high-sugar food reward was assessed using a 3-criteria model similar to that used to assess addiction-like behaviour towards drugs of abuse. In contrast to findings in rats, no difference in addiction-like behaviour towards food was observed between obesity prone (OP) and obesity resistant (OR) mice. Similarly, principal components analysis found no distinct patterns in the relationship between addiction-like behaviours across treatment groups. This suggests that the strain and species of rodent may be critical for studying the mechanisms underlying pathological overconsumption. Further analysis revealed that the extent of performance on the 3-criteria model correlated with the propensity for C57BL/6 J mice to both extinguish food seeking behaviour and "relapse" after a period of withdrawal. This finding was evident across all groups, regardless of DIO. Collectively, these data validate the 3-criteria model as a robust model to comprehensively assess food addiction-like behaviour in mice, regardless of prior food intake history.

Food Addiction: A Comprehensive Review

Food addiction is associated with dysfunctions in the reward circuit, such as hyperresponsiveness during the exposure to high-calorie flavors in overweight and obese individuals. Similar to drug addiction, there is also impaired self-regulatory control supported by deregulation of the frontostriatal circuit. The inclusion of validated measures of food addiction in clinical research, such as the Yale Food Addiction Scale, has increased the understanding of the clinical utility of this concept. Furthermore, food addiction, eating disorders, and obesity are interrelated. Thus, it is important to recognize food addiction among individuals affected by obesity and candidates for bariatric surgery (ie, preoperative and postoperative assessment). In this context, it has been reported that food addiction may impede weight loss and increase the likelihood of regaining weight when associated with personality traits such as neuroticism and impulsiveness, which are also related to mood disorders, anxiety, and addictive behaviors.

Disentangling binge eating disorder and food addiction: a systematic review and meta-analysis

BACKGROUND AND AIMS

The concept of "Food Addiction" has been based on criteria of Substance Use Disorder. Several studies suggested a relationship between food addiction and eating disorders, but little is known about its extent or role. We aim at exploring if food addiction is coincident with a specific eating disorder (binge eating disorder appears the closest) or it is a separate diagnostic entity that afflicts in comorbidity with eating disorders or other conditions like obesity or even in the general population.

METHODS

This systematic review and meta-analysis analyzed observational studies with a comparative estimation on rates of subjects affected by binge eating disorder and food addiction.

RESULTS

Binge eating disorder shows higher comorbidity with food addiction compared to other eating disorders (OR = 1.33, 95% CI, 0.64-2.76; c² = 4.42; p = 0.44;I² = 0%), or each eating disorder [anorexia nervosa purging type (OR = 1.93, 95% CI, 0.20-18.92; p = 0.57) and restrictive type (OR = 8.75, 95% CI, 1.08-70.70; p = 0.04)], obese patients (OR = 5.72, 95% CI, 3.25-10.09; p =  < 0.0001) and individuals from the general population (OR = 55.41, 95% CI, 8.16-376.10; c² = 18.50; p < 0.0001; I² = 0%)but has decreased prevalence when compared to bulimia nervosa (OR = 0.85, 95% CI, 0.33-2.22; c² = 0.35; p = 0.74; I² = 0%).

DISCUSSION AND CONCLUSIONS

Our data show that the prevalence of food addiction in binge eating disorder is higher than in other eating disorders except in bulimia nervosa. Moreover, it is a separate diagnostic reality and can be detected in people without mental illness and in the general population. Food addiction might have a prognostic value, since in comorbidity, and should be addressed to boost treatment efficacy and patient's recovery.

LEVEL OF EVIDENCE

I: Evidence obtained systematic reviews and meta-analyses.

Integrative Hedonic and Homeostatic Food Intake Regulation by the Central Nervous System: Insights from Neuroimaging

Food intake regulation in humans is a complex process controlled by the dynamic interaction of homeostatic and hedonic systems. Homeostatic regulation is controlled by appetitive signals from the gut, adipose tissue, and the vagus nerve, while conscious and unconscious reward processes orchestrate hedonic regulation. On the one hand, sight, smell, taste, and texture perception deliver potent food-related feedback to the central nervous system (CNS) and influence brain areas related to food reward. On the other hand, macronutrient composition stimulates the release of appetite signals from the gut, which are translated in the CNS into unconscious reward processes. This multi-level regulation process of food intake shapes and regulates human ingestive behavior. Identifying the interface between hormones, neurotransmitters, and brain areas is critical to advance our understanding of conditions like obesity and develop better therapeutical interventions. Neuroimaging studies allow us to take a glance into the central nervous system (CNS) while these processes take place. This review focuses on the available neuroimaging evidence to describe this interaction between the homeostatic and hedonic components in human food intake regulation.

Lower synaptic density is associated with psychiatric and cognitive alterations in obesity

Obesity is a serious medical condition that often co-occurs with stress-related psychiatric disorders. It is recognized that the brain plays a key role in the (patho)physiology of obesity and that there is a bidirectional relationship between obesity and psychopathology, yet molecular mechanisms altered in obesity have not been fully elucidated. Thus, we investigated relationships between obesity and synaptic density in vivo using the radioligand [11C]UCB-J (which binds to synaptic glycoprotein SV2A) and positron emission tomography in individuals with obesity, and with or without stress-related psychiatric disorders. Regions of interest were the dorsolateral prefrontal cortex, orbitofrontal cortex, ventromedial, amygdala, hippocampus, and cerebellum. Forty individuals with a body mass index (BMI) ≥ 25 kg/m2 (overweight/obese), with (n = 28) or without (n = 12) psychiatric diagnosis, were compared to 30 age- and sex-matched normal weight individuals (BMI < 25), with (n = 14) or without (n = 16) psychiatric diagnosis. Overall, significantly lower synaptic density was observed in overweight/obese relative to normal weight participants (ηp2 = 0.193, F = 2.35, p = 0.042). Importantly, in participants with stress-related psychiatric diagnoses, we found BMI to be negatively correlated with synaptic density in all regions of interest (p ≤ 0.03), but no such relationship observed for mentally healthy controls (p ≥ 0.68). In the stress-related psychiatric groups, dorsolateral prefrontal cortex synaptic density was negatively associated with measures of worry (r = -0.46, p = 0.01), tension/anxiety (r = -0.38, p = 0.04), fatigue (r = -0.44, p = 0.02), and attentional difficulties (r = -0.44, p = 0.02). In summary, the findings of this novel in vivo experiment suggest compounding effects of obesity and stress-related psychopathology on the brain and the associated symptomatology that may impact functioning. This offers a novel biological mechanism for the relationship between overweight/obesity and stress-related psychiatric disorders that may guide future intervention development efforts.

Highly processed food addiction: A concept analysis

AIM

This concept analysis aims to clarify the highly processed food addiction (HPFA) concept and discuss its implications for treating obesity.

BACKGROUND

Emerging empirical evidence suggests addictive-like eating may contribute to obesity in some individuals, increasing interest in HPFA's role in obesity. Clarifying the HPFA concept will aid in developing individualized interventions for patients with obesity and HPFA.

DESIGN

This concept analysis followed Walker and Avant's approach. The case studies are of participants in a study that included individuals with and without HPFA (Yale Food Addiction Scale 2.0-diagnosed).

DATA SOURCE

We searched PubMed, CINAHL, PsychInfo, and Ebscohost databases. Keywords were "food addiction" and "food addiction concept."

REVIEW METHODS

Criteria included recent reviews and empirical studies that measured HPFA and focused on HPFA characteristics and/or treatment implications.

RESULTS

The model case displayed all 11-substance use disorder (SUD) symptoms and clinical significance, supporting a severe HPFA diagnosis. The contrary case was negative for all YFAS 2.0 symptoms and clinical significance and did not eat compulsively or experience cravings. The borderline case met the minimum symptom criteria for severe HPFA but not clinical significance. Clinical interviews may help determine whether such individuals truly exhibit addictive-like eating behaviors.

CONCLUSIONS

Growing empirical evidence and our case studies support the HPFA concept and the utility of the YFAS/YFAS 2.0 for identifying a distinct subset of individuals with overweight/obesity who may benefit from interventions developed to treat established SUDs. Future research should examine HPFA separately and in relation to obesity and eating disorders and include longitudinal studies and gender-balanced samples.

Weight Stigma and Disease and Disability Concepts of Obesity: A Survey of the German Population

INTRODUCTION

Recent years have witnessed a medicalization of obesity, promoting a classification as a disease or disability in order to reduce or protect against weight stigma and discrimination. This study sought to investigate the public understanding of the disability and disease concepts in obesity, their acceptance, and association with weight stigma.

METHODS

In a representative German population sample (n = 2,524), public views of obesity as a disease or disability were assessed via a self-report questionnaire. For the assessment of weight stigma, the Weight Control/Blame subscale from the Antifat Attitudes Test was used.

RESULTS

A significantly greater acceptance of the disease than the disability concept was found (37.1 vs. 15.4%). Both disease and disability were mainly viewed as physical conditions, although one-third also viewed obesity as a mental disease. While agreement with the disease concept - especially of physical and genetic disease - significantly predicted lower weight stigma; agreement with the disability concept - especially of mental or intellectual disability - predicted higher weight stigma.

CONCLUSIONS

These results suggest a careful use of the disease and disability terms and precise definitions. The disability concept in particular carries notions that are publicly devalued.

Clusterin levels in undernourished SH-SY5Y cells

Food-related disorders are increasingly common in developed societies, and the psychological component of these disorders has been gaining increasing attention. Both overnourishment with high-fat diets and perinatal undernourishment in mice have been linked to a higher motivation toward food, resulting in an alteration in food intake. Clusterin (CLU), a multifaced protein, is overexpressed in the nucleus accumbens (NAc) of over-fed rats, as well as in those that suffered chronic undernutrition. Moreover, an increase of this protein was observed in the plasma of obese patients with food addiction, suggesting the implication of CLU in this eating disorder. To characterize CLU’s cellular mechanisms, in vitro experiments of undernutrition were performed using dopaminergic SH-SY5Y cells. To mimic in vivo dietary conditions, cells were treated with different fetal bovine serum (FBS) concentrations, resulting in control (C group) diet (10% FBS), undernourishment (U group) diet (0.5% FBS), and undernourishment diet followed by restoration of control diet (UC group) (0.5 + 10% FBS). Undernourishment compromised cell viability and proliferation, and concomitantly increased CLU secretion as well as the cytosolic pool of the protein, while decreasing the mitochondrial level. The restoration of normal conditions tended to recover cell physiology, and the normal levels and distribution of CLU. This research study is a step forward toward the characterization of clusterin as a potential marker for food addiction and nutritional status.

A Systematic Review of Obesity and Binge Eating Associated Impairment of the Cognitive Inhibition System

Altered functioning of the inhibition system and the resulting higher impulsivity are known to play a major role in overeating. Considering the great impact of disinhibited eating behavior on obesity onset and maintenance, this systematic review of the literature aims at identifying to what extent the brain inhibitory networks are impaired in individuals with obesity. It also aims at examining whether the presence of binge eating disorder leads to similar although steeper neural deterioration. We identified 12 studies that specifically assessed impulsivity during neuroimaging. We found a significant alteration of neural circuits primarily involving the frontal and limbic regions. Functional activity results show BMI-dependent hypoactivity of frontal regions during cognitive inhibition and either increased or decreased patterns of activity in several other brain regions, according to their respective role in inhibition processes. The presence of binge eating disorder results in further aggravation of those neural alterations. Connectivity results mainly report strengthened connectivity patterns across frontal, parietal, and limbic networks. Neuroimaging studies suggest significant impairment of various neural circuits involved in inhibition processes in individuals with obesity. The elaboration of accurate therapeutic neurocognitive interventions, however, requires further investigations, for a deeper identification and understanding of obesity-related alterations of the inhibition brain system.

Sugar intake and craving during alcohol withdrawal in alcohol use disorder inpatients

To assess whether changes in sugar intake and craving occur during alcohol withdrawal in humans, we conducted a prospective, observational study in a university hospital addictions treatment center. Recruited patients had severe alcohol use disorder and were hospitalized for 7 days in the short-stay unit for alcohol withdrawal and then for 6 weeks in the rehabilitation unit. During the hospital stay, they had no access to alcohol but had full access to sweet products and beverages in a shop and vending machines located inside the hospital. Alcohol craving was assessed using a visual analogue scale on Days 1, 15, and 45. Sugar craving, sweet products stored by patients in their rooms, and weight were assessed on the same days. Thirty-five patients were included. Sugar craving increased in 14 patients during the hospital stay, whereas no change was observed in the remaining 21. Significant increases in both the amounts of sweet products stored in the patients' rooms (p < 0.02) and weight (p < 0.05) were observed only in the sugar craving group. During the same period, alcohol craving decreased significantly in all patients. Changes in tobacco smoking were not different according to the sugar craving status and therefore cannot explain the observed differences. In conclusion, increased intake and craving for sugar after alcohol withdrawal were observed in 40% of the patients included in our prospective study, and these results were similar to those of a study conducted in the alcohol post-dependent state model in rats.

Food Addiction among Female Patients Seeking Treatment for an Eating Disorder: Prevalence and Associated Factors

The concept of "food addiction" (FA) has aroused much focus because of evidence for similarities between overeating and substance use disorders (SUDs). However, few studies have explored this concept among the broad spectrum of eating disorders (ED), especially in anorexia nervosa (AN). This study aimed to assess FA prevalence in ED female patients and to determine its associated factors. We recruited a total of 195 adult women with EDs from an ED treatment center. The prevalence of FA diagnosis (Yale Food Addiction Scale) in the whole ED sample was 83.6%; AN restrictive type (AN-R), 61.5%; AN binge-eating/purging type (AN-BP), 87.9%; bulimia nervosa (BN), 97.6%; and binge-eating disorder (BED), 93.3%. The most frequently met criteria of FA were "clinically significant impairment or distress in relation to food", "craving" and "persistent desire or repeated unsuccessful attempts to cut down". An FA diagnosis was independently associated with three variables: presence of recurrent episodes of binge eating, ED severity, and lower interoceptive awareness. In showing an overlap between ED and FA, this study allows for considering EDs, and AN-R in particular, from an "addictive point of view", and thus for designing therapeutic management that draws from those proposed for addictive disorders.

Overexpression of corticotropin-releasing factor in the nucleus accumbens enhances the reinforcing effects of nicotine in intact female versus male and ovariectomized female rats

This study assessed the role of stress systems in the nucleus accumbens (NAc) in promoting sex differences in the reinforcing effects of nicotine. Intravenous self-administration (IVSA) of various doses of nicotine was compared following overexpression of corticotropin-releasing factor (CRF) in the NAc of female and male rats. Ovariectomized (OVX) females were also included to assess the role of ovarian hormones in promoting nicotine reinforcement. Rats received intra-NAc administration of an adeno-associated vector that overexpressed CRF (AAV2/5-CRF) or green fluorescent protein (AAV2/5-GFP). All rats were then given extended access (23 h/day) to an inactive and an active lever that delivered nicotine. Separate groups of rats received intra-NAc AAV2/5-CRF and saline IVSA. Rats were also allowed to nose-poke for food and water during IVSA testing. At the end of the study, the NAc was dissected and rt-qPCR methods were used to estimate CRF overexpression and changes in CRF receptors (CRFr1, CRFr2) and the CRF receptor internalizing protein, β-arrestin2 (Arrb2). Overexpression of CRF in the NAc increased nicotine IVSA to a larger extent in intact female versus male and OVX females. Food intake was increased to a larger extent in intact and OVX females as compared to males. The increase in CRF gene expression was similar across all groups; however, in females, overexpression of CRF resulted in a larger increase in CRFr1 and CRFr2 relative to males. In males, overexpression of CRF produced a larger increase in Arrb2 than females, suggesting greater CRF receptor internalization. Our results suggest that stress systems in the NAc promote the reinforcing effectiveness of nicotine in female rats in an ovarian hormone-dependent manner.

Identifying the relationship between biological, psychosocial and family markers associated with childhood obesity: Case-control "ANOBAS" study

The recent increase in childhood obesity prevalence rates illustrates the extreme relevance of biological, psychosocial and familial factors implicated in body weight status, which at the moment remain unclear. The study aims to compare biological, psychosocial and familial markers between preadolescents with obesity and their non-overweight peers, and explore the relationship with psychiatric diagnosis on these markers. Both groups were composed of 40% of males with a mean age of 10 years, and no differences in socio-demographic variables were found between groups. No sex differences were found on bio/psycho/family markers. While 48% (n = 24) of the preadolescents with obesity presented a DSM-IV diagnosis (OGD), only 2% (n = 1) of the non-overweight peers (NG) met diagnostic criteria. Significant differences were found for all bio/psycho/family markers among obese preadolescents with the exceptions of cortisol, peptide YY and maternal state-anxiety and depression. The preadolescents with obesity without a diagnosis (OGND) presented greater levels of leptin than NG (p = 0.01). For psychosocial markers, statistically significant differences were found between groups in the majority of the variables (p <  0.01), with the exception of trait anxiety where a tendency towards significance was revealed (p = 0.06). For family markers, we found statistically significant differences in emotional over-involvement (p = 0.01), with NG mothers presenting lower scores than OGD and OGND. Include psychosocial and family factors in obesity intervention programs is necessary. Also, health professionals working with children with obesity must take care to assess the presence of a psychiatric diagnosis amongst this population.

Links between traumatic experiences in childhood or early adulthood and lifetime binge eating disorder

OBJECTIVES

To evaluate the association between childhood or early adulthood traumatic experiences and adulthood binge eating disorder (BED) in 326 male and 1158 female patients. A structured clinical interview for the DSM-IV (SCID-I/P)-adapted to lifetime exploration for the diagnosis of BED and for DSM-IV Childhood Disorders was conducted by the psychiatrist.

RESULTS

Emotional neglect was the most frequent event experienced (77.8% of females vs. 63.5% of males, p < 0.0001), ahead of physical abuse (23.3%), witnessed domestic violence (17.7%) and sexual abuse (11.8% of females vs. 2.8% of males (p < 0.0001)). The prevalence rate for BED in the whole population was 34.9%. The independent predictors for BED were emotional neglect in male obese patients (OR = 3.49; IC95% (1.94-6.29); p < 0.0001) and physical abuse (OR = 1.56; IC95% (1.14-2.12); p = 0.0047), emotional neglect (OR = 1.83; IC95% (1.37-2.44); p < 0.0001), and sexual abuse (OR = 1.80; IC95% (1.22-2.65); p = 0.0029) in female patients. With a cut-off value of 17, the sensitivity of the Binge Eating Scale for BED during lifetime was 50.8% with 74.7% specificity.

CONCLUSIONS

This study shows that early psychological events are independent predictors of BED in obese female and male adults. The BES questionnaire is a poor predictor of BED during lifetime and a structured clinical interview should be recommended.

Affective startle modulation and psychopathology: Implications for appetitive and defensive brain systems

Startle reflex potentiation versus startle attenuation to unpleasant versus pleasant stimuli likely reflect priming of the defensive versus appetitive motivational systems, respectively. This review summarizes and systemizes the literature on affective startle modulation related to psychopathologies with the aim to reveal underlying mechanisms across psychopathologies. We found evidence for psychopathologies characterized by increased startle potentiation to unpleasant stimuli (anxiety disorders), decreased startle potentiation to unpleasant stimuli (psychopathy), decreased startle attenuation to pleasant stimuli (ADHD), as well as a general hyporeactivity to affective stimuli (depression). Increased versus decreased startle responses to disorder-specific stimuli characterize specific phobia and drug dependence. No psychopathology is characterized by increased startle attenuation to standard pleasant stimuli or a general hyperreactivity to affective stimuli. This review indicates that the defensive and the appetitive systems operate independently mostly in accordance with the motivational priming hypothesis and that affective startle modulation is a highly valuable paradigm to unraveling dysfunctions of the defensive and appetitive systems in psychopathologies as requested by the Research Domain Criteria initiative.

Shared Behavioral and Neurocircuitry Disruptions in Drug Addiction, Obesity, and Binge Eating Disorder: Focus on Group I mGluRs in the Mesolimbic Dopamine Pathway

Accumulated data from clinical and preclinical studies suggest that, in drug addiction and states of overeating, such as obesity and binge eating disorder (BED), there is an imbalance in circuits that are critical for motivation, reward saliency, executive function, and self-control. Central to these pathologies and the extensive topic of this Review are the aberrations in dopamine (DA) and glutamate (Glu) within the mesolimbic pathway. Group I metabotropic glutamate receptors (mGlus) are highly expressed in the mesolimbic pathway and are poised in key positions to modulate disruptions in synaptic plasticity and neurotransmitter release observed in drug addiction, obesity, and BED. The use of allosteric modulators of group I mGlus has been studied in drug addiction, as they offer several advantages over traditional orthosteric agents. However, they have yet to be studied in obesity or BED. With the substantial overlap between the neurocircuitry involved in drug addiction and eating disorders, group I mGlus may also provide novel targets for obesity and BED.

Impulse control disorders in Parkinson's disease: A systematic review on risk factors and pathophysiology

AIM

Purpose of this review is to evaluate the potential risk factors that may predispose to the development of Impulse control disorders (ICDs) in Parkinson's Disease (PD) patients, including the effects of dopaminergic therapy.

METHODS

This descriptive review was conducted to identificate risk factors that could cause impulsive control disorders in PD. Studies were found on PubMed (2010-2018), Web Of Science (January 2010-July 2018) and Cochrane (2010-2018) databases.

RESULTS

The data suggest that intrinsic and extrinsic factors may be involved in the development of behavioral complications. To date, the link between PD and the development of ICDs is not very clear, but studies highlight the existence of a predisposition to ICDs in the presence of risk factors.

CONCLUSIONS

A better assessment of the behavioral disorders of PD may be useful in the rehabilitative intervention for increasing the quality of life.

Establishing a food addiction diagnosis using the Yale Food Addiction Scale: A closer look at the clinically significant distress/functional impairment criterion

The concept of food addiction (FA) represents a set of problematic eating behaviors related to overeating. According to the Yale Food Addiction Scale (YFAS), which was based on the DSM-IV-TR substance dependence diagnostic criteria, a FA diagnosis is assigned when at least three criteria and the criterion evaluating clinically significant distress and/or functional impairment are endorsed. Considering the decisive role of this last criterion, the present study aimed to investigate its endorsement among individuals suffering from severe obesity and awaiting bariatric surgery. A total of 146 individuals were recruited at the Quebec Heart and Lung Institute and were invited to complete various questionnaires. Differences between individuals who endorsed at least three FA criteria and reported distress/impairment (FA+D/I; N = 24) and individuals who endorsed at least three FA criteria but did not report distress/impairment (FA-D/I; N = 27) were examined. Results revealed that 16% of the total sample fulfilled a FA diagnosis when considering the clinically significant distress/functional impairment criterion; however, this prevalence rate climbed to 35% when removing the inclusion of distress/impairment. Furthermore, individuals from the FA+D/I group showed more FA symptomatology and hedonic hunger, but did not statistically differ from the FA-D/I group on expected markers of psychological distress (depressive symptoms and quality of life). Lastly, the experience of withdrawal symptoms and hedonic hunger were found to be the best predictors of the endorsement of the distress/impairment criterion. This study underlines the impact of this criterion in establishing a FA diagnosis and highlights the importance of considering alternative ways to interpret findings from the YFAS when dealing with clinical samples.

MOSH Syndrome (Male Obesity Secondary Hypogonadism): Clinical Assessment and Possible Therapeutic Approaches

Male obesity secondary hypogonadism (MOSH) impairs fertility, sexual function, bone mineralization, fat metabolism, cognitive function, deteriorates muscle mass and alters body composition. The aim of this pilot study was to evaluate the effect of dietary intervention and physical activity on the MOSH patient’s hormonal profile after a 10% weight loss compared to baseline. Fourteen male patients were enrolled. Hormonal, lipid, glycemic profiles and body composition were determined at baseline and after a 10% weight loss. Aging Male Symptoms Scale (AMS) and Yale Food Addiction Scale (YFAS) were administered to patients in order to investigate hypogonadal symptoms and food addiction. Compared to baseline, a significant increase of Total Testosterone (TT) (300.2 ± 79.5 ng/dL vs. 408.3 ± 125.9 ng/dL, p = 0.002, 95% CI 26.8; 167.7) and a reduction of 17-Beta Estradiol level (48.3 ± 14.9 pg/mL vs. 39.2 ± 15.2 pg/mL, p = 0.049, 95% CI 3.1; 0.0) were observed. Total Fat Mass (FM) percentage, android and gynoid fat mass percentage (39.2 ± 6.4% vs. 36.2 ± 5.8%, p = 0.0001, 95% CI 22.5; 62.3; 51.5 ± 6.8% vs. 47.6 ± 6.8%, p = 0.001, 95% CI 0.6; 1.8, vs. 39.2 ± 6.2% vs. 36.5 ± 6.3% p = 0.0001, 95% CI 0.9; 2.0 respectively) were significantly decreased after nutritional intervention. In addition, total Fat Free Mass (FFM) in kg was significantly reduced after 10% weight loss (62.3 ± 2.8 kg vs. 60.3 ± 7.7 kg, p = 0.002, 95% CI 45.0; 93.0). Lifestyle changes, specifically dietotherapy and physical activity, induce positive effects on hypogonadism due to obesity.

Extinction and reinstatement of an operant responding maintained by food in different models of obesity

A major problem in treating obesity is the high rate of relapse to abnormal food-taking habits after maintaining an energy balanced diet. Alterations of eating behavior such as compulsive-like behavior and lack of self-control over food intake play a critical role in relapse. In this study, we used an operant paradigm of food-seeking behavior on two different diet-induced obesity models, a free-choice chocolate-mixture diet and a high-fat diet with face validity for a rapid development of obesity or for unhealthy food regularly consumed in our societies. A reduced operant performance and motivation for the hedonic value of palatable chocolate pellets was revealed in both obesity mouse models. However, only mice exposed to high-fat diet showed an increased compulsive-like behavior in the absence of the reinforcer further characterized by impaired operant learning, enhanced impulsivity and intensified inflexibility. We used principal component analysis to globally identify the specific behaviors responsible for the differences among diet groups. Learning impairment and inflexible behaviors contributed to a first principal component, explaining the largest proportion of the variance in the high-fat diet mice phenotype. Reinforcement, impulsion and compulsion were the main contributors to the second principal component explaining the differences in the chocolate-mixture mice behavioral phenotype. These behaviors were not exclusive of chocolate group because some high-fat individuals showed similar values on this component. These data indicate that extended access to hypercaloric diets differentially modifies operant behavior learning, behavioral flexibility, impulsive-like and compulsive-like behavior, and these effects were dependent on the exposure to each specific diet.

Sugars, exercise and health

BACKGROUND

There is a direct link between a variety of addictions and mood states to which exercise could be relieving. Sugar addiction has been recently counted as another binge/compulsive/addictive eating behavior, differently induced, leading to a high-significant health problem. Regularly exercising at moderate intensity has been shown to efficiently and positively impact upon physiological imbalances caused by several morbid conditions, including affective disorders. Even in a wider set of physchiatric diseases, physical exercise has been prescribed as a complementary therapeutic strategy.

METHOD

A comprehensive literature search was carried out in the Cochrane Library and MEDLINE databases (search terms: sugar addiction, food craving, exercise therapy, training, physical fitness, physical activity, rehabilitation and aerobic).

RESULTS

Seeking high-sugar diets, also in a reward- or craving-addiction fashion, can generate drastic metabolic derangements, often interpolated with affective disorders, for which exercise may represent a valuable, universal, non-pharmachological barrier.

LIMITATIONS

More research in humans is needed to confirm potential exercise-mechanisms that may break the bond between sugar over-consumption and affective disorders.

CONCLUSIONS

The purpose of this review is to address the importance of physical exercise in reversing the gloomy scenario of unhealthy diets and sedentary lifestyles in our modern society.

Altered Dopamine Synaptic Markers in Postmortem Brain of Obese Subjects

Dopaminergic signaling in the reward pathway in the brain has been shown to play an important role in food intake and the development of obesity. Obese rats release less dopamine (DA) in the nucleus accumbens (NAc) after food intake, and amphetamine stimulated striatal DA release is reduced in vivo in obese subjects. These studies suggest that DA hypofunction associated with hedonic dysregulation is involved in the pathophysiology of obesity. To identify brain changes in obesity, quantitative measures of DA synaptic markers were compared in postmortem brain tissues of normal weight and obese subjects over a range of increasing body mass indices (BMI). DA transporter (DAT) numbers in the striatum were compared to the relative expression of DAT, tyrosine hydroxylase (TH) and D2 dopamine receptors (DRD2) in midbrain DA neurons. Radioligand binding assays of [³H]WIN35,428 demonstrated that the number of striatal DAT binding sites was inversely correlated with increasing BMI (r = −0.47; p < 0.01). DAT and TH gene expression were significantly decreased in the somatodendritic compartment of obese subjects (p < 0.001), with no significant change in DRD2 compared to normal weight subjects. The reduced density of striatal DAT with corresponding reductions in DAT and TH gene expression in substantia nigra (SN) suggests, that obesity is associated with hypodopaminergic function. A DA reward deficiency syndrome has been suggested to underlie abnormal eating behavior that leads to obesity. Neurobiological changes in presynaptic DA markers demonstrated postmortem in human brain support a link between hedonic DA dysregulation and obesity.

Overlapping Neural Endophenotypes in Addiction and Obesity

Impulsivity refers to a tendency to act rapidly without full consideration of consequences. The trait is thought to result from the interaction between high arousal responses to potential rewards and poor self-control. Studies have suggested that impulsivity confers vulnerability to both addiction and obesity. However, results in this area are unclear, perhaps due to the high phenotypic complexity of addictions and obesity. Focusing on impulsivity, the aim of this review is to tackle the putative overlaps between addiction and obesity in four domains: (1) personality research, (2) neurocognitive tasks, (3) brain imaging, and (4) clinical evidence. We suggest that three impulsivity-related domains are particularly relevant for our understanding of similarities between addiction and obesity: lower self-control (high Disinhibition/low Conscientiousness), reward sensitivity (high Extraversion/Positive Emotionality), and negative affect (high Neuroticism/Negative Emotionality). Neurocognitive studies have shown that obesity and addiction are both associated with increased impulsive decision-making and attention bias in response to drug or food cues, respectively. Mirroring this, obesity and different forms of addiction seem to exhibit similar alterations in functional MRI brain activity in response to reward processing and during self-control tasks. Overall, our review provides an integrative approach to understand those facets of obesity that present similarities to addictive behaviors. In addition, we suggest that therapeutic interventions targeting inhibitory control may represent a promising approach for the prevention and/or treatment of obesity.

Problem Drinking, Gambling and Eating – Three Problems, One Understanding? A Qualitative Comparison between French and Finnish Social Workers

Aim

Culture Is often used as a wildcard in cross-cultural studies. This article proposes a more diverse understanding of culture, as layered from “deep structures” towards institutional arrangements. It analyses which cultural levels are involved in Finnish and French social workers' understanding of problem drinking, gambling and eating.

Design

A stimulated focus group method (Reception Analytical Group Interview) RAGI was applied to eight groups of Finnish and five groups of French social workers not specialised in addiction. The interviews were analysed with a semi-otic approach.

Results

Finnish social workers understand problem drinking, gambling and eating as rooted in society and harming the social environment. It is the individual's responsibility to solve the problem. French social workers conceptualise only problem eating similar to problem drinking as being caused by an individual defect. They identify problem gambling as a social issue.

Conclusions

The results imply that both the institutional context and structures deeper in culture influence how we conceptualise excessive behaviours. This shows the usefulness of a layered concept of culture. The article recommends caution in using “addiction” as an umbrella concept for all kinds of excessive behaviours, as the perception of each problem depends not only on culture, but on the different cultural levels. Problem gambling in particular seems to evoke multiple understandings.

Obesity: Current and potential pharmacotherapeutics and targets

Obesity is a global epidemic that contributes to a number of health complications including cardiovascular disease, type 2 diabetes, cancer and neuropsychiatric disorders. Pharmacotherapeutic strategies to treat obesity are urgently needed. Research over the past two decades has increased substantially our knowledge of central and peripheral mechanisms underlying homeostatic energy balance. Homeostatic mechanisms involve multiple components including neuronal circuits, some originating in hypothalamus and brain stem, as well as peripherally-derived satiety, hunger and adiposity signals that modulate neural activity and regulate eating behavior. Dysregulation of one or more of these homeostatic components results in obesity. Coincident with obesity, reward mechanisms that regulate hedonic aspects of food intake override the homeostatic regulation of eating. In addition to functional interactions between homeostatic and reward systems in the regulation of food intake, homeostatic signals have the ability to alter vulnerability to drug abuse. Regarding the treatment of obesity, pharmacological monotherapies primarily focus on a single protein target. FDA-approved monotherapy options include phentermine (Adipex-P®), orlistat (Xenical®), lorcaserin (Belviq®) and liraglutide (Saxenda®). However, monotherapies have limited efficacy, in part due to the recruitment of alternate and counter-regulatory pathways. Consequently, a multi-target approach may provide greater benefit. Recently, two combination products have been approved by the FDA to treat obesity, including phentermine/topiramate (Qsymia®) and naltrexone/bupropion (Contrave®). The current review provides an overview of homeostatic and reward mechanisms that regulate energy balance, potential therapeutic targets for obesity and current treatment options, including some candidate therapeutics in clinical development. Finally, challenges in anti-obesity drug development are discussed.

Obesity as a Socially Defined Disease: Philosophical Considerations and Implications for Policy and Care

Obesity has generated significant worries amongst health policy makers and has obtained increased attention in health care. Obesity is unanimously defined as a disease in the health care and health policy literature. However, there are pragmatic and not principled reasons for this. This warrants an analysis of obesity according to standard conceptions of disease in the literature of philosophy of medicine. According to theories and definitions of disease referring to (abnormal functioning of) internal processes, obesity is not a disease. Obesity undoubtedly can result in disease, making it a risk factor for disease, but not a disease per se. According to several social conceptions of disease, however, obesity clearly is a disease. Obesity can conflict with aesthetic, moral, or other social norms. Making obesity a "social disease" may very well be a wise health policy, assuring and improving population health, especially if we address the social determinants of obesity, such as the food supply and marketing system. However, applying biomedical solutions to social problems may also have severe side effects. It can result in medicalization and enhance stigmatization and discrimination of persons based on appearance or behavior. Approaching social problems with biomedical means may also serve commercial and professionals' interests more than the health and welfare of individuals; it may make quick fix medical solutions halt more sustainable structural solutions. This urges health insurers, health care professionals, and health policy makers to be cautious. Especially if we want to help and respect persons that we classify and treat as obese.

A Substance Called Food: Long-Term Psychodynamic Group Treatment for Compulsive Overeating

Obesity has proven difficult to treat. Many approaches neglect to address the deep-rooted underlying psychological issues. This paper describes a psychodynamically oriented approach to treating compulsive overeating as an addiction. Common to all addictions is a compulsion to consume a substance or engage in a behavior, a preoccupation with using behavior and rituals, and a lifestyle marked by an inability to manage the behavior and its harmful consequences. The approach represents a shift away from primarily medical models of intervention to integrated models focusing on the psychological underpinnings of obesity. Long-term psychodynamic group psychotherapy is recommended as a primary treatment.

Brain reward system's alterations in response to food and monetary stimuli in overweight and obese individuals

The brain's reward system is crucial to understand obesity in modern society, as increased neural responsivity to reward can fuel the unhealthy food choices that are driving the growing obesity epidemic. Brain's reward system responsivity to food and monetary rewards in individuals with excessive weight (overweight and obese) versus normal weight controls, along with the relationship between this responsivity and body mass index (BMI) were tested. The sample comprised 21 adults with obesity (BMI > 30), 21 with overweight (BMI between 25 and 30), and 39 with normal weight (BMI < 25). Participants underwent a functional magnetic resonance imaging (fMRI) session while performing two tasks that involve the processing of food (Willing to Pay) and monetary rewards (Monetary Incentive Delay). Neural activations within the brain reward system were compared across the three groups. Curve fit analyses were conducted to establish the association between BMI and brain reward system's response. Individuals with obesity had greater food-evoked responsivity in the dorsal and ventral striatum compared with overweight and normal weight groups. There was an inverted U-shape association between BMI and monetary-evoked responsivity in the ventral striatum, medial frontal cortex, and amygdala; that is, individuals with BMIs between 27 and 32 had greater responsivity to monetary stimuli. Obesity is associated with greater food-evoked responsivity in the ventral and dorsal striatum, and overweight is associated with greater monetary-evoked responsivity in the ventral striatum, the amygdala, and the medial frontal cortex. Findings suggest differential reactivity of the brain's reward system to food versus monetary rewards in obesity and overweight. Hum Brain Mapp 38:666-677, 2017. © 2016 Wiley Periodicals, Inc.

The novel cannabinoid antagonist SM-11 reduces hedonic aspect of food intake through a dopamine-dependent mechanism

Cannabinoids, endogenous and exogenously administered, are known to positively regulate food intake and energy balance. Since CB1 receptor antagonists reduce food intake and antagonize overweight, we developed a new CB1 receptor antagonist in an attempt to identify a compound with potential application in overeating disorders. The newly developed SM-11 compound dose-dependently decreases food intake in rats by 15-20%. Moreover, SM-11 reduces self-administration of palatable food in both food restricted and ad libitum fed rats, suggesting an action on the hedonic component of food intake. Thus, we next tested the effect of SM-11 on the stimulating properties of the CB1 receptor agonist WIN55,212-2 (WIN) on the electrophysiological activity of Nucleus Accumbens-projecting dopaminergic neurons of the ventral tegmental area (VTA). SM-11 fully and readily antagonized the WIN-induced increments in single spiking and burst firing of antidromically-identified dopamine neurons. When administered to naïve (no WIN-pretreated) rats, SM-11 did not alter basal neuronal activity, thereby suggesting a pure antagonistic profile. SM-11 thus appears as a promising candidate in the search of potential anti-obesity medications.

The Neurobiology of "Food Addiction" and Its Implications for Obesity Treatment and Policy

There is a growing view that certain foods, particularly those high in refined sugars and fats, are addictive and that some forms of obesity can usefully be treated as a food addiction. This perspective is supported by a growing body of neuroscience research demonstrating that the chronic consumption of energy-dense foods causes changes in the brain's reward pathway that are central to the development and maintenance of drug addiction. Obese and overweight individuals also display patterns of eating behavior that resemble the ways in which addicted individuals consume drugs. We critically review the evidence that some forms of obesity or overeating could be considered a food addiction and argue that the use of food addiction as a diagnostic category is premature. We also examine some of the potential positive and negative clinical, social, and public policy implications of describing obesity as a food addiction that require further investigation.

The Influence of Palatable Diets in Reward System Activation: A Mini Review

The changes in eating patterns that have occurred in recent decades are an important cause of obesity. Food intake and energy expenditure are controlled by a complex neural system involving the hypothalamic centers and peripheral satiety system (gastrointestinal and pancreatic hormones). Highly palatable and caloric food disrupts appetite regulation; however, palatable foods induce pleasure and reward. The cafeteria diet is such a palatable diet and has been shown consistently to increase body weight and induce hyperplasia in animal obesity models. Moreover, palatable high-fat foods (such as those of the cafeteria diet) can induce addiction-like deficits in brain reward function and are considered to be an important source of motivation that might drive overeating and contribute to the development of obesity. The mechanism of neural adaptation triggered by palatable foods is similar to those that have been reported for nondrug addictions and long-term drug use. Thus, this review attempts to describe the potential mechanisms that might lead to highly palatable diets, such as the cafeteria diet, triggering addiction, or compulsion through the reward system.

The Obesities: An Overview of Convergent and Divergent Paradigms

The study of obesity lends itself to difficulties not only due to our imprecise ability to measure body composition, food consumption, and physical activity but also, even more important, due to complexities involved in defining and conceptualizing obesity. For centuries, obesity has been considered a disease, although researchers and clinicians cannot agree on definitions of "disease" or, if it is one, whether obesity is a disease of metabolism, inflammation, brown fat, chronobiology, the blood-brain barrier, the right brain, or even of infectious origin. The concept of "obesity" as a disease remains controversial to some because not everyone who has excess adipose tissue has any evidence of disease. Obesity, though, has also been considered a sin, a crime against society, an aesthetic crime, a self-inflicted disability, an example of body diversity, a failure in the regulation of energy balance, an appropriate or even inappropriate adaptation to our increasingly obesogenic environment, a genetic disorder, and a psychological/behavioral disorder of overeating involving self-regulation or even addiction. Five major paradigms-medical, sociocultural, evolutionary, environmental, and psychological/behavioral, all with their own subcategorical models-have been identified. All 5 paradigms are required because we are dealing not with "obesity" but with a plurality, the "obesities."

Impact of plasma transaminase levels on the peripheral blood glutamate levels and memory functions in healthy subjects

Background & aims

Blood aspartate aminotransferase (AST) and alanine transaminase (ALT) levels are the most frequently reliable biomarkers of liver injury. Although AST and ALT play central roles in glutamate production as transaminases, peripheral blood levels of AST and ALT have been regarded only as liver injury biomarkers. Glutamate is a principal excitatory neurotransmitter, which affects memory functions in the brain. In this study, we investigated the impact of blood transaminase levels on blood glutamate concentration and memory.

Methods

Psychiatrically, medically, and neurologically healthy subjects (n = 514, female/male: 268/246) were enrolled in this study through local advertisements. Plasma amino acids (glutamate, glutamine, glycine, d-serine, and l-serine) were measured using a high performance liquid chromatography system. The five indices, verbal memory, visual memory, general memory, attention/concentration, and delayed recall of the Wechsler Memory Scale-Revised were used to measure memory functions.

Results

Both plasma AST and ALT had a significant positive correlation with plasma glutamate levels. Plasma AST and ALT levels were significantly negatively correlated with four of five memory functions, and plasma glutamate was significantly negatively correlated with three of five memory functions. Multivariate analyses demonstrated that plasma AST, ALT, and glutamate levels were significantly correlated with memory functions even after adjustment for gender and education.

Conclusions

As far as we know, this is the first report which could demonstrate the impact of blood transaminase levels on blood glutamate concentration and memory functions in human. These findings are important for the interpretation of obesity-induced metabolic syndrome with elevated transaminases and cognitive dysfunction.

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Peripheral blood levels of AST and ALT have been regarded only as liver injury biomarkers.

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In healthy human subjects, both plasma AST and ALT had significant positive correlations with plasma glutamate levels.

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Plasma AST, ALT, and glutamate levels were significantly negatively correlated with memory functions in univariate and multivariate analyses.

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As far as we know, this is the first report which could demonstrate the impact of blood transaminase levels on blood glutamate concentration and memory functions in human.

Genetic variants in the CPNE5 gene are associated with alcohol dependence and obesity in Caucasian populations

Alcohol addiction may increase the risk of obesity due to shared genetic components. The Copine V (CPNE5) gene is involved in Ca(2+) binding and may play an important role in the development of the central nervous system. This study tested the genetic associations of 77 single-nucleotide polymorphisms (SNPs) within the CPNE5 gene with alcohol dependence (AD) and obesity using a Caucasian sample - The Study of Addiction - Genetics and Environment (SAGE) sample (1066 AD cases and 1278 non-AD controls, 422 obese cases and 1395 non-obese controls). The Marshfield sample (1442 obese cases and 2122 non-obese controls) was used for replication of obesity. Multiple logistic regression analysis was performed using the PLINK software. In the SAGE sample, we identified 10 SNPs associated with AD and 17 SNPs associated with obesity (p < 0.05). Interestingly, 6 SNPs (rs9986517, rs9470387, rs3213534, rs10456444, rs3752482, and rs9470386) were associated with both AD (OR = 0.77, 0.77, 0.83, 0.84, 0.79 and 1.14, respectively; p = 9.72 × 10(-5), 1.1 × 10(-4), 4.09 × 10(-3), 5.26 × 10(-3), 1.59 × 10(-2), and 3.81 × 10(-2), respectively) and obesity (OR = 0.77, 0.77, 0.78, 0.77, 0.68 and 1.18, respectively; p = 2.74 × 10(-3), 2.69 × 10(-3), 2.45 × 10(-3), 1.01 × 10(-3), 5.18 × 10(-3) and 3.85 × 10(-2), respectively). In the Marshfield sample, rs3752480 was associated with obesity (p = 0.0379). In addition, four SNPs (rs9986517, rs10456444, rs7763347 and rs4714010) showed associations with obesity in the meta-analysis using both samples (p = 0.00493, 0.0274, 0.00346, and 0.0141, respectively). These findings provide the first evidence of common genetic variants in the CPNE5 gene influencing both the AD and obesity; and will serve as a resource for replication in other populations.

A Shared Molecular and Genetic Basis for Food and Drug Addiction: Overcoming Hypodopaminergic Trait/State by Incorporating Dopamine Agonistic Therapy in Psychiatry

This article focuses on the shared molecular and neurogenetics of food and drug addiction tied to the understanding of reward deficiency syndrome. Reward deficiency syndrome describes a hypodopaminergic trait/state that provides a rationale for commonality in approaches for treating long-term reduced dopamine function across the reward brain regions. The identification of the role of DNA polymorphic associations with reward circuitry has resulted in new understanding of all addictive behaviors.

The use of repetitive transcranial magnetic stimulation for modulating craving and addictive behaviours: a critical literature review of efficacy, technical and methodological considerations

OBJECTIVES

Repetitive transcranial magnetic stimulation (rTMS) is a potential therapeutic intervention for the treatment of addiction. This critical review aims to summarise the recent developments with respect to the efficacy of rTMS for all types of addiction and related disorders (including eating disorders), and concentrates on the associated methodological and technical issues.

METHODS

The bibliographic search consisted of a computerised screening of the Medline and ScienceDirect databases up to December 2013. Criteria for inclusion were the target problem was an addiction, a related disorder, or craving; the intervention was performed using rTMS; and the study was a clinical trial.

RESULTS

Of the potential 638 articles, 18 met the criteria for inclusion. Most of these (11 of the 18) supported the efficacy of rTMS, especially in the short term. In most cases, the main assessment criterion was the measurement of craving using a Visual Analogue Scale.

DISCUSSION

The results are discussed with respect to the study limitations and, in particular, the many methodological and technical discrepancies that were identified. Key recommendations are provided.

Therapeutic Potential of 5-HT2C Receptor Agonists for Addictive Disorders

The neurotransmitter 5-hydroxytryptamine (5-HT; serotonin) has long been associated with the control of a variety of motivated behaviors, including feeding. Much of the evidence linking 5-HT and feeding behavior was obtained from studies of the effects of the 5-HT releaser (dex)fenfluramine in laboratory animals and humans. Recently, the selective 5-HT2C receptor agonist lorcaserin received FDA approval for the treatment of obesity. This review examines evidence to support the use of selective 5-HT2C receptor agonists as treatments for conditions beyond obesity, including substance abuse (particularly nicotine, psychostimulant, and alcohol dependence), obsessive compulsive, and excessive gambling disorder. Following a brief survey of the early literature supporting a role for 5-HT in modulating food and drug reinforcement, we propose that intrinsic differences between SSRI and serotonin releasers may have underestimated the value of serotonin-based pharmacotherapeutics to treat clinical forms of addictive behavior beyond obesity. We then highlight the critical involvement of the 5-HT2C receptor in mediating the effect of (dex)fenfluramine on feeding and body weight gain and the evidence that 5-HT2C receptor agonists reduce measures of drug reward and impulsivity. A recent report of lorcaserin efficacy in a smoking cessation trial further strengthens the idea that 5-HT2C receptor agonists may have potential as a treatment for addiction. This review was prepared as a contribution to the proceedings of the 11th International Society for Serotonin Research Meeting held in Hermanus, South Africa, July 9-12, 2014.

Foods and dietary profiles associated with 'food addiction' in young adults

Background

It has been suggested that addictive behaviors related to consumption of specific foods could contribute to overeating and obesity. Although energy-dense, hyper-palatable foods are hypothesized to be associated with addictive-like eating behaviors, few studies have assessed this in humans.

Objective

To evaluate in young adults whether intakes of specific foods are associated with ‘food addiction’, as assessed by the Yale Food Addiction Scale (YFAS), and to describe the associated nutrient intake profiles.

Design

Australian adults aged 18–35 years were invited to complete an online cross-sectional survey including demographics, the YFAS and usual dietary intake. Participants were classified as food addicted (FAD) or non-addicted (NFA) according to the YFAS predefined scoring criteria.

Results

A total 462 participants (86% female, 73% normal weight) completed the survey, with 14.7% (n = 68) classified as FAD. The FAD group had a higher proportion of females (p = .01) and higher body mass index (p < .001) compared to NFA. Higher YFAS symptom scores were associated with higher percentage energy intake (%E) from energy-dense, nutrient-poor foods including candy, take out and baked sweet products, as well as lower %E from nutrient-dense core foods including whole-grain products and breakfast cereals. These remained statistically significant when adjusted for age, sex and BMI category (p = .001).

Conclusions

Statistically significant associations were identified between YFAS assessed food addiction and dietary intake, specifically intakes of energy-dense, nutrient-poor foods. However, the effect sizes were small limiting clinical applications. Further examination of the relationship between addictive-like eating and intake of specific foods in a nationally representative sample is warranted.

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14.7% participants met the YFAS predefined criteria for food addiction.

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Those classified as food addicted had a significantly higher body mass index.

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Higher symptom scores related to higher intakes of energy-dense nutrient-poor foods

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Lower odds of YFAS assessed food addiction with higher intakes of whole-grains.

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Higher odds of YFAS assessed food addiction with higher intakes of dietary fat.