Psychophysiological responses to idiosyncratic stress in bulimia nervosa and binge eating disorder

This study examined psychophysiological stress responses to idiosyncratically relevant stress in bulimia nervosa (BN) and binge eating disorder (BED), in relation to autonomic cardiac control and nutritional status. A total of 81 women with BN, BED and healthy controls (HC) took part in an in sensu exposure to idiosyncratic stress. Psychological and peripheral physiological parameters were measured, and tonic heart rate variability, nutritional status, and types of stress were determined. In response to stress exposure, both eating disordered groups showed a stronger reactivity of sadness, and the BED group showed a stronger reactivity of insecurity than the HC group. Desire to binge was increased in the context of interpersonal stress. Stress exposure led to increased cardiovascular activity and reduced electrodermal activity that did not differ by group. The BN-specific symptomatology moderated the association between autonomic cardiac control and psychophysiological stress responses. The results suggest common and specific psychophysiological processes in symptom maintenance through life stress in BN and BED.     

Participation and outcome in manualized self-help for bulimia nervosa and binge eating disorder — A systematic review and metaregression analysis

There is a growing body of research on manualized self-help interventions for bulimia nervosa (BN) and binge eating disorder (BED). Study and treatment dropout and adherence represent particular challenges in these studies. However, systematic investigations of the relationship between study, intervention and patient characteristics, participation, and intervention outcomes are lacking. We conducted a systematic literature review using electronic databases and hand searches of relevant journals. In metaregression analyses, we analyzed study dropout as well as more specific measures of treatment participation in manualized self-help interventions, their association with intervention characteristics (e.g. duration, guidance, intervention type [bibliotherapy, CD-ROM or Internet based intervention]) and their association with treatment outcomes. Seventy-three publications reporting on 50 different trials of manualized self-help interventions for binge eating and bulimia nervosa published through July 9th 2012 were identified. Across studies, dropout rates ranged from 1% to 88%. Study dropout rates were highest in CD-ROM interventions and lowest in Internet-based interventions. They were higher in samples of BN patients, samples of patients with higher degrees of dietary restraint at baseline, lower age, and lower body mass index. Between 6% and 88% of patients completed the intervention to which they had been assigned. None of the patient, study and intervention characteristics predicted intervention completion rates. Intervention outcomes were moderated by the provision of personal guidance by a health professional, the number of guidance sessions as well as participants' age, BMI, and eating disorder related attitudes (Restraint, Eating, Weight and Shape Concerns) at baseline (after adjusting for study dropout and intervention completion rates). Guidance particularly improved adherence and outcomes in samples of patients with bulimia nervosa; specialist guidance led to higher intervention completion rates and larger intervention effects on some outcomes than non-specialist guidance. Self-help interventions have a place in the treatment of BN and BED, especially if the features of their delivery and indications are considered carefully. To better determine who benefits most from what kind and “dosage” of self-help interventions, we recommend the use of consistent terminology as well as uniform standards for reporting adherence and participation in future self-help trials.     

Serum amylase in bulimia nervosa and purging disorder: differentiating the association with binge eating versus purging behavior

Objective

Elevated serum amylase levels in bulimia nervosa (BN), associated with increased salivary gland size and self-induced vomiting in some patients, provide a possible marker of symptom severity. The goal of this study was to assess whether serum hyperamylasemia in BN is more closely associated with binge eating episodes involving consumption of large amounts of food or with purging behavior.

Method

Participants included women with BN (n = 26); women with “purging disorder” (PD), a subtype of EDNOS characterized by recurrent purging in the absence of objectively large binge eating episodes (n = 14); and healthy non-eating disorder female controls (n = 32). There were no significant differences in age or body mass index (BMI) across groups. The clinical groups reported similar frequency of self-induced vomiting behavior and were free of psychotropic medications. Serum samples were obtained after overnight fast and were assayed for alpha-amylase by enzymatic method.

Results

Serum amylase levels were significantly elevated in BN (60.7 ± 25.4 international units [IU]/liter, mean ± sd) in comparison to PD (44.7 ± 17.1 IU/L, p < .02) and to Controls (49.3 ± 15.8, p < .05).

Conclusion

These findings provide evidence to suggest that it is recurrent binge eating involving large amounts of food, rather than self-induced vomiting, which contributes to elevated serum amylase values in BN.     

Feeding and reward: perspectives from three rat models of binge eating

Research has focused on understanding how overeating can affect brain reward mechanisms and subsequent behaviors, both preclinically and in clinical research settings. This work is partly driven by the need to uncover the etiology and possible treatments for the ongoing obesity epidemic. However, overeating, or non-homeostatic feeding behavior, can occur independent of obesity. Isolating the variable of overeating from the consequence of increased body weight is of great utility, as it is well known that increased body weight or obesity can impart its own deleterious effects on physiology, neural processes, and behavior. In this review, we present data from three selected animal models of normal-weight non-homeostatic feeding behavior that have been significantly influenced by Bart Hoebel's 40+-yr career studying motivation, feeding, reinforcement, and the neural mechanisms that participate in the regulation of these processes. First, a model of sugar bingeing is described (Avena/Hoebel), in which animals with repeated, intermittent access to a sugar solution develop behaviors and brain changes that are similar to the effects of some drugs of abuse, serving as the first animal model of food addiction. Second, another model is described (Boggiano) in which a history of dieting and stress can perpetuate further binge eating of palatable and non-palatable food. In addition, a model (Boggiano) is described that allows animals to be classified as having a binge-prone vs. binge-resistant behavioral profile. Lastly, a limited access model is described (Corwin) in which non-food deprived rats with sporadic limited access to a high-fat food develop binge-type behaviors. These models are considered within the context of their effects on brain reward systems, including dopamine, the opioids, cholinergic systems, serotonin, and GABA. Collectively, the data derived from the use of these models clearly show that behavioral and neuronal consequences of bingeing on a palatable food, even when at a normal body weight, are different from those that result from simply consuming the palatable food in a non-binge manner. These findings may be important in understanding how overeating can influence behavior and brain chemistry.     

No association of the Arg51Gln and Leu72Met polymorphisms of the ghrelin gene with anorexia nervosa or bulimia nervosa

Genetic factors likely contribute to the biological vulnerability to anorexia nervosa (AN) and bulimia nervosa (BN). We investigated whether the Arg51Gln and/or the Leu72Met gene polymorphisms of the human ghrelin, a peptide involved in the regulation of eating behavior, were associated to AN and/or BN. Two-hundred-ninety-two Caucasian women (114 with BN, 59 with AN and 119 healthy controls) participated into the study. No significant differences were found in the frequencies of the Arg51Gln and the Leu72Met ghrelin gene variants among patients with AN or BN and healthy controls. Moreover, no significant differences emerged in eating-related phenotypic variables between patients carrying the Leu72Met genotype as compared to those with the Leu72Leu genotype. These results suggest that the Arg51Gln and the Leu72Met polymorphisms of the human ghrelin gene do not contribute to the genetic susceptibility to AN and BN.     

A possible association between the Val158Met polymorphism of the catechol-O-methyl transferase gene and the personality trait of harm avoidance in Japanese healthy subjects

Catechol-O-methyltransferase (COMT) is an enzyme that degrades various biogenic amines, which have been hypothesized to be associated with personality traits. We investigated a possible relationship between the COMT Val158Met polymorphism and personality traits assessed by the Temperament and Character Inventory (TCI) in 139 healthy subjects in a Japanese population. The number of Met alleles of the COMT Val/Met genotype tended to relate to harm avoidance (HA) scores parametrically, while no significant difference was observed between genotype groups in either novelty seeking, reward dependence, persistence, self-directedness, cooperativeness or self-transcendence. These results suggest that the Val/Met polymorphism of the COMT gene may play a role in HA in Japanese population.     

Hypomania across the binge eating spectrum. A study on hypomanic symptoms in full criteria and sub-threshold binge eating subjects

Backgrounds

Obese subjects affected by binge eating can be distinguished between those showing full criteria Binge Eating Disorder (BED) and those who show binge eating of insufficient frequency to satisfy DSM criteria, or sub-threshold BED (s-BED). The present paper aims to investigate whether subjects with BED full criteria show more hypomanic symptoms than those with s-BED, after controlling for personality variables as potential confounders.

Methods

The Hypomania Checklist (HCL-32), the Beck Depression Inventory (BDI) and the Temperament and Character Inventory (TCI) were administered to 103 obese patients with binge eating.

Results

Full criteria BED subjects were more likely to be female and showed higher HCL-32 scores and lower scores in character dimensions (Self-directedness and Cooperativeness) compared to s-BED subjects. A logistic regression with Eating Disorder Diagnosis as outcome measure (BED or s-BED) revealed that lower Cooperativeness, higher Hypomania scores and female sex predicted having BED full criteria.

Limitations

Further research is necessary to replicate these findings in a larger sample.

Conclusions

Patients with more severe binge eating might be more likely to have a comorbid bipolar spectrum disorder. Hypomanic symptoms should be assessed and mood stabilizing treatment should be considered in these patients.     

Association between the estrogen receptor TA polymorphism and Harm avoidance

In the last decade a large number of studies focused on the recognition of gene variants modulating temperamental traits. The gene coding for the estrogen receptor alpha (ESR1) appears to be an interesting candidate and it has been found to be linked to Harm avoidance (HA). The aim of the present study was to investigate whether the ESR1 TA dinucleotide repeat polymorphism is associated with HA temperamental trait in a sample of Caucasian University students. One hundred ninety healthy subjects were genotyped for ESR1 TA dinucleotide repeat polymorphism and were administered the Temperament and Character Inventory (TCI). ESR1 TA repeat lengths were dichotomized into short and long categories. ANOVA was used to examine the influence of ESR1 variants (short/long) on the means of the TCI HA scores. HA was significantly associated with age and gender in our sample, being higher in older and female subjects. In the global sample as well as in men and women separately, individuals carrying the S/S variant showed significantly higher HA scores. Further analysis on the HA subscales revealed that specific differences could exist between men and women. Our results further suggest a possible role of ESR1 variants on HA. Further research is needed to replicate our findings as well as to better explore the neuro-biological mechanisms of the modulation of ESR1 on HA.     

A review of the definitions of outcome used in the treatment of bulimia nervosa

There are many terms used to describe treatment outcome for bulimia nervosa. However, the way such terms are conceptualised across various studies differs dramatically, making comparison of outcomes difficult. A consensus working definition of pivotal terms such as remission and recovery is important if treatments are to be adequately evaluated and clinical meaning derived for individuals with bulimia nervosa (BN). The central aim of the current review was to identify different definitions of remission and recovery and their utility in terms of client outcome after treatment for BN. Seventy one unique published treatment studies were identified that used 82 different outcome measures, of which 63 (77%) used behavioural outcomes only, with the most commonly used outcome (n=7 studies) being an abstinence of bingeing and vomiting for a 4 week period. The problems with the definitions of outcomes used to date are explored, and the implications of research in anorexia nervosa for forming consensus definitions of remission and recovery for BN will be examined. In addition, the review highlights the importance of considering the relationship between quality of life and outcome in assessing the "goodness of fit" of a definition of outcome.     

Investigation of 3111T/C polymorphism of the CLOCK gene in obese individuals with or without binge eating disorder: Association with higher body mass index

Loss of circadian patterning of metabolism-related functions seems to play a role in the pathogenesis of obesity; therefore, it is reasonable to hypothesize that the functional 3111T/C single nucleotide polymorphism (SNP) of the (Circadian locomotor output cycles kaput) CLOCK gene may have a part in the genetic susceptibility to obesity. The aim of this study was to assess the frequencies of 3111T/C CLOCK gene SNP in overweight/obese subjects with or without binge eating disorder (BED) as compared to normal weight healthy controls. A total of 284 Caucasian subjects, including 92 normal weight healthy subjects and 192 overweight/obese patients (107 with BED) participated into the study. Genotype and allele frequencies did not significantly differ between normal weight controls and overweight/obese patients with and/or without BED. However, overweight/obese patients carrying the CC genotype had significantly higher values of body mass index (BMI) as compared to those carrying the CT and/or TT genotypes. Moreover, obese class III individuals had a significantly higher frequency of both the CC genotype and the C allele as compared to individuals with BMI < 40 kg/m². Present findings show for the first time that the 3111T/C SNP of the CLOCK gene is not associated to human obesity and/or BED, but it seems to predispose obese individuals to a higher BMI.     

IFN-γ基因多态性与小儿哮喘的相关性

目的探讨IFN-γ基因多态性、等位基因在儿童哮喘发病机理中的意义。方法采用PCR-SSP方法对30例小儿哮喘病儿及26例非哮喘呼吸道疾病患儿作IFN-γ基因多态性分析。结果30例哮喘组IFN-γ基因型中,T/T1例,T/A7例,A/A22例,26例非哮喘组IFN-γ基因型中,T/T7例,T/A11例,A/A8例。χ2=11.696,P<0.005,两组IFN-γ基因型有明显差异。哮喘组IFN-γ等位基因T和A的频率为15%和85%,非哮喘组IFN-γ等位基因T和A的频率为51.9%和48.1%,哮喘组IFN-γ等位基因A的频率比非哮喘组IFN-γ等位基因A高,相对危险度0.191,95%可信度区间0.078-0.466,χ2=14.416,P<0.005,两组IFN-γ等位基因频率有明显差异。结论本研究证实小儿哮喘易感性与IFN-γ基因启动子多态性相关联。     

The 196G/A (val66met) polymorphism of the BDNF gene is significantly associated with binge eating behavior in women with bulimia nervosa or binge eating disorder

The brain-derived neurotrophic factor (BDNF) is involved not only in promoting neuronal outgrowth and differentiation, synaptic connectivity and neuronal repair, but also in modulating eating behavior. Since genetic factors likely contribute to the biological vulnerability to bulimia nervosa (BN) and binge eating disorder (BED), we investigated whether the functional 196G/A single nucleotide polymorphism (SNP) of the BDNF gene was associated to BN and/or BED or to some phenotypic aspects of the disordered eating. Two hundred and ten Caucasian women (126 with BN, 84 with BED and 121 healthy controls) participated into the study. No significant differences were found in the frequencies of the 196G/A variants of the BDNF gene among patients with BN or BED and healthy controls. In both BN and BED groups, subjects carrying the 196A/A genotype exhibited a weekly frequency of bingeing and a severity of binge eating (as assessed by the Bulimia Investigation Test Edinburgh) significantly higher than those with the 196A/G and 196G/G genotypes. These results suggest that the 196G/A SNP of the human BDNF gene does not contribute to the genetic susceptibility to BN and BED, but may predispose those patients to a more severe binge eating behavior.     

A double-blind,placebo-controlled trial of fluvoxamine in binge eating disorder: a high placebo response

Summary Twenty subjects with binge eating disorder were randomly assigned to flexible-dose fluvoxamine or placebo for 12 weeks. A significant reduction in binge frequency, Beck Depression Inventory scores and the eating concern, shape concern and weight concern subscales of the Eating Disorder Examination were noted for both fluvoxamine (n = 9) and placebo (n = 11) groups. There were no significant differences between fluvoxamine and placebo for any treatment outcome variables. The findings from this small trial contribute to the inconsistent results of antidepressant studies in binge eating disorder. Received August 7, 2002; accepted January 26, 2003 Published online April 23, 2003 RID="*" ID="*"  This study was presented as a poster at the 9^th International Conference on Eating Disorders, May, 2000, New York, NY. Supported in part by a grant from Solvay Pharmaceuticals. Correspondence: Teri Pearlstein, M.D., Assistant Professor, Department of Psychiatry and Human Behavior, Brown Medical School, Director, Women's Behavioral Health Program, Women and Infants Hospital, 101 Dudley Street, Providence, RI 02905, U.S.A.; e-mail: Teri_Pearlstein@brown.edu     

HLA-DQA1基因多态性和HBV感染结局的关联

目的 探讨人类白细胞抗原(HLA)DQA1基因多态性与乙型肝炎病毒(HBV)感染临床结局的关联.方法 临床收集慢性乙型肝炎(120例)、慢性HBV携带者(60例)、自限性HBV感染者(60例)三组病例,前两组诊断均经肝活检证实.聚合酶链反应序列特异性引物(PCR-SSP)法检测HLA-DQA1基因型,比较组间基因频率的差异.结果 (1)HLA-DQA1*0201在慢性乙型肝炎组的分布频率显著高于自限性HBV感染组(38.3% vs 5.8%,P<0.001,A=10.04,95% CI:4.48～22.48);HLA-DQA1*0102的分布频率显著低于自限性HBV感染组(9.6% vs 36.7%,P<0.001,A=0.183,95%CI:0.10～0.32).(2)HLA-DQA1*0201在慢性乙型肝炎组的分布频率显著高于慢性HBV携带者组(38.3% vs 7.5%,P<0.01,A=7.667,95% CI:3.7～15.87);HLA-DQA1*0102的分布频率显著低于慢性HBV携带者(20% vs 9.6%.P<0.01,A=0.424,95% CI:0.23～0.79).结论 HLA-DQAI基因多态性影响HBV感染临床结局,其中DQA1*0102呈保护作用,DQA1*0201可能促进HBV感染的慢性化和肝炎的发生.     

Conceptualizing the role of estrogens and serotonin in the development and maintenance of bulimia nervosa

Serotonergic dysregulation is thought to underlie much of the pathology in bulimia nervosa (BN). The purpose of this review is to expand the serotonergic model by incorporating specific and nonspecific contributions of estrogens to the development and maintenance of bulimic pathology in order to guide research from molecular genetics to novel therapeutics for BN. Special emphasis is given to the organizing theory of general brain arousal which allows for integration of specific and nonspecific effects of these systems on behavioral endpoints such as binge eating or purging as well as arousal states such as fear, novelty seeking, or sex. Regulation of the serotonergic system by estrogens is explored, and genetic, epigenetic, and environmental estrogen effects on bulimic pathology and risk factors are discussed. Genetic and neuroscientific research support this two-system conceptualization of BN with both contributions to the developmental and maintenance of the disorder. Implications of an estrogenic–serotonergic model of BN are discussed as well as guidelines and suggestions for future research and novel therapeutic targets.     

A new animal model of binge eating: key synergistic role of past caloric restriction and stress

Dieting and stress are important in the etiology and maintenance of eating disorders, and dieting strongly predicts stress-induced overeating in humans. We hypothesized that caloric restriction and stress interact in a unique manner to promote binge eating. To test this hypothesis, a group of young female rats were cycled through a restriction period (4 days of 66% of control food intake) followed by 6 days of free feeding prior to being stressed by acute foot shock. After three of these cycles, the food intake of rats exposed only to restriction (R), or only to stress (S), did not differ from controls. However, R+S rats that were restricted and refed, despite normal body weight and food intake after free feeding, engaged in a powerful bout of hyperphagia when stressed (Experiment 1). The R + S effect was replicated in an older group of rats (Experiment 2). The hyperphagia was characteristically binge-like, it constituted a 40% selective increase in highly palatable (HP) food (P < .001) over a discrete period of time (within 24 h post-stress), and reflected feeding for reward (higher HP:chow ratio) over metabolic need as occurred after restriction (higher chow:HP ratio). Subsequent experiments revealed that binge eating did not occur if only chow was available (Experiment 3) or if restriction-refeeding (R-R) did not proximally precede stress (Experiment 4). Experiment 5 revealed that a history of R-R cycles followed by only one stress episode was sufficient to increase intake to 53% above controls as early as 2 h after stress (P < .001). This animal model of binge eating should facilitate investigations into the neurochemical changes induced by dieting and environmental stress to produce disordered eating and provide a preclinical tool to test preventive strategies and treatments more relevant to bulimia nervosa, multiple cases of binge eating disorder (BED) and binge-purge type anorexia nervosa.     

Food scarcity, neuroadaptations, and the pathogenic potential of dieting in an unnatural ecology: binge eating and drug abuse

In the laboratory, food restriction has been shown to induce neuroadaptations in brain reward circuitry which are likely to be among those that facilitate survival during periods of food scarcity in the wild. However, the upregulation of mechanisms that promote foraging and reward-related learning may pose a hazard when food restriction is self-imposed in an ecology of abundant appetitive rewards. For example, episodes of loss of control during weight-loss dieting, use of drugs with addictive potential as diet aids, and alternating fasting with alcohol consumption in order to avoid weight gain, may induce synaptic plasticity that increases the risk of enduring maladaptive reward-directed behavior. In the present mini-review, representative basic research findings are outlined which indicate that food restriction alters the function of mesoaccumbens dopamine neurons, potentiates cellular and behavioral responses to D-1 and D-2 dopamine receptor stimulation, and increases stimulus-induced synaptic insertion of AMPA receptors in nucleus accumbens. Possible mechanistic underpinnings of increased drug reward magnitude, drug-seeking, and binge intake of sucrose in food-restricted animal subjects are discussed and possible implications for human weight-loss dieting are considered.     

相同来源HIV-1 Env、Gag基因序列变异和宿主基因多态性与疾病进展关系的分析

目的探讨HIV—1基因序列变异和宿主基因多态性与疾病进展的关系。方法PCR方法从外周血细胞中扩增HIV—1 Env、Gag区片段和测序，分析序列变异、糖基化，超突变等指标。RFLP法确定宿主基因多态性。结果未治疗组中，env基因区PCR和克隆序列平均离散率分别为0．1和0．06，差异有统计学意义，治疗组内差异没有统计学意义。V3环顶端序列在未治疗和治疗组中均以GPGQ比例最大（61．5％和39％），治疗组出现稀有多肽序列如GPGH、GQGR、GLGR、12位I／V和21位Y／H变异与疾病快速进展相关。Env区段上进展较快速组（RRP）比典型进展组（TP）的糖基化程度高（平均值分别为14．56和13．20个），差异有统计学意义。Env区段上RRP比TP组GA取代百分率和绝对数平均值都高（8．7％／6．9％和10．1／7．6），差异也有统计学意义。TP组中SDF1—3’A和CCR2V62I基因频率均高于RRP组，但差异没有统计学意义。CX3CR1 V249I／M280T与疾病快速进展没有显著相关性。结论V3区序列主要位点的氨基酸变异、Env区段糖基化程度、GA取代与疾病进展相关。SDF1—3’A、CCR2V641和CX3CR1 2491／280M与疾病进展均无显著相关性。     

A Psychoneuroendocrino-immune approach in the nursing treatment of anorexia and bulimia nervosa

Recent clinical reports have shown an increasing number of patients afflicted by eating disorders in the western world. There are numerous causes and mechanisms leading to eating disorders that affect the psychoneuroendocrinoimmune system. In this study, we define a novel psychoneuroendocrinoimmune nursing approach for anorexic and bulimic patients&rsquo; treatment. According to the specific diagnostic items deriving from the Diagnostic and Statistical Manual of Mental Disorders and the International Classification of Diseases, and clinical guidelines in eating disorders formulated by the National Institute for Clinical Excellence, we carried out a qualitative study on the nursing treatment chosen by 210 international centers considered as a sample. This study was based on a no structured interview via e-mail to better understand the nursing approach in anorexia and bulimia nervosa. Thanks to the selected centers&rsquo; answers, four different levels of nursing care were identified, that include:

1. the nursing role analyzing the spectrum of patients&rsquo; problems;

2. the nursing intervention in inpatient care;

3. the nursing intervention in outpatient care;

4. the day hospital treatment.

All four prove to be especially useful in the nursing practice.