Childhood anxiety associated with low BMI in women with anorexia nervosa

Three daily intraperitoneal injections of sub-anesthetic ketamine ameliorate activity-based anorexia vulnerability of adult female mice

OBJECTIVE

To identify ketamine's dosing schedule that ameliorates voluntary food restriction, hyperactivity and body weight loss of adult mice undergoing activity-based anorexia (ABA), an animal model of anorexia nervosa.

METHOD

Female and male C57BL6 mice underwent three cycles of ABA, starting from mid-adolescence. ABA vulnerability was compared within and across two groups of animals: those injected intraperitoneally with 30 mg/kg ketamine for three consecutive days (30mgKetx3) during the second ABA in late adolescence (ABA2) or with vehicle only (Vx3).

RESULTS

Vx3 females and males exhibited individual differences in wheel running and weight retention during first ABA in mid-adolescence (ABA1), ABA2, and third ABA in adulthood (ABA3). Their wheel running correlated with anxiety-like behavior. During ABA1 and ABA3, weight gain of Vx3 females (but not males) after food consumption correlated negatively with food-anticipatory activity (FAA) preceding the feeding hours, indicating that females with higher levels of running restrict feeding more and persistently. This paradoxical relationship confirms earlier findings of ABA females without ketamine treatment, capturing the maladaptive behaviors exhibited by individuals diagnosed with anorexia nervosa. By contrast, 30mgKetx3 had an effect on both sexes of reducing hyperactivity during the feeding hours acutely and reducing anxiety-like behavior's contribution to running. For females, only, 30mgKetx3 acutely improved the extent of compensatory food consumption relative to FAA and improved weight retention during ABA3, 12 days post ketamine in adulthood.

DISCUSSION

Sub-anesthetic ketamine evokes behavior-specific ameliorative effects for adult mice re-experiencing ABA, supporting the notion that multiple doses of ketamine may be helpful in reducing relapse among adults with anorexia nervosa.

PUBLIC SIGNIFICANCE STATEMENT

This study examined whether ketamine reduces anorexia-like behaviors in adult mice. Three daily sub-anesthetic ketamine injections suppress wheel running during and leading up to the hours of food availability and enable animals to compensate better for weight loss associated with excessive exercise by eating more. These findings suggest that ketamine may help adult females diagnosed with anorexia nervosa but also point to sex- and age-related differences in the action of ketamine.

Testing anxiety and reward processing in anorexia nervosa as predictors of longitudinal clinical outcomes

Anorexia nervosa (AN) is a psychiatric disorder with a tenuous longitudinal course marked by a high risk of relapse. Previous studies suggest that aberrant threat perception and reward processing operate in many with AN, and may produce obstacles to treatment engagement; therefore, these could potentially represent predictors for longitudinal clinical outcomes. In this study, anxiety and reward symptoms, behaviors, and neural circuit connectivity were measured in intensively treated AN-restrictive subtype patients (n = 33) and healthy controls (n = 31). Participants underwent an fMRI experiment using a monetary reward task in combination with either overlapping individually tailored anxiety-provoking words or neutral words. Behavioral/psychometric measures consisted of reaction times on the monetary reward task and self-ratings on anxiety symptoms at study entry. We tested multimodal, multivariate models based on neural, behavioral, and psychometric measures of reward and anxiety to predict physiological (Body Mass Index; BMI) and psychological (eating disorder symptom severity) longitudinal outcomes in AN over six months. Our results indicated that higher anxiety symptom psychometric scores significantly predicted BMI reductions at follow-up. Untreated anxiety after intensive treatment could put individuals with AN at heightened risk for weight loss. This represents a potentially modifiable risk factor that could be targeted more aggressively to help reduce the chance of future clinical worsening.

Risk factors for eating disorders: findings from a rapid review

BACKGROUND

Risk factors represent a range of complex variables associated with the onset, development, and course of eating disorders. Understanding these risk factors is vital for the refinement of aetiological models, which may inform the development of targeted, evidence-based prevention, early intervention, and treatment programs. This Rapid Review aimed to identify and summarise research studies conducted within the last 12 years, focusing on risk factors associated with eating disorders.

METHODS

The current review forms part of a series of Rapid Reviews to be published in a special issue in the Journal of Eating Disorders, funded by the Australian Government to inform the development of the National Eating Disorder Research and Translation Strategy 2021-2031. Three databases were searched for studies published between 2009 and 2021, published in English, and comprising high-level evidence studies (meta-analyses, systematic reviews, moderately sized randomised controlled studies, moderately sized controlled-cohort studies, or population studies). Data pertaining to risk factors for eating disorders were synthesised and outlined in the current paper.

RESULTS

A total of 284 studies were included. The findings were divided into nine main categories: (1) genetics, (2) gastrointestinal microbiota and autoimmune reactions, (3) childhood and early adolescent exposures, (4) personality traits and comorbid mental health conditions, (5) gender, (6) socio-economic status, (7) ethnic minority, (8) body image and social influence, and (9) elite sports. A substantial amount of research exists supporting the role of inherited genetic risk in the development of eating disorders, with biological risk factors, such as the role of gut microbiota in dysregulation of appetite, an area of emerging evidence. Abuse, trauma and childhood obesity are strongly linked to eating disorders, however less conclusive evidence exists regarding developmental factors such as role of in-utero exposure to hormones. Comorbidities between eating disorders and mental health disorders, including personality and mood disorders, have been found to increase the severity of eating disorder symptomatology. Higher education attainment, body image-related factors, and use of appearance-focused social media are also associated with increased risk of eating disorder symptoms.

CONCLUSION

Eating disorders are associated with multiple risk factors. An extensive amount of research has been conducted in the field; however, further studies are required to assess the causal nature of the risk factors identified in the current review. This will assist in understanding the sequelae of eating disorder development and in turn allow for enhancement of existing interventions and ultimately improved outcomes for individuals.

Rapid refeeding does not worsen anxiety in adolescents with anorexia nervosa: a pilot study

The study aimed to describe the progression of state anxiety in adolescents with anorexia nervosa (AN) hospitalized on a high calorie refeeding (HCR) protocol. Participants, 12-21 years, admitted for malnutrition due to AN were placed on a HCR protocol in which calories were advanced by 300 kcal/day. The State-Trait Anxiety Inventory for Children (STAIC) was given to participants within 24 hours of hospitalization and the state anxiety component of the STAIC was administered daily immediately before and after breakfast until discharge. Of 22 patients enrolled, 86% were female, mean age was 14.9 ± 2.0 years, and 95% had AN-restrictive type. The median state and trait anxiety scores at time of admission were 37.0 (28-55) and 35.5 (23-51), respectively. There was no significant difference in median pre-meal state anxiety from hospital day 1 to 6 (34.0(26-55) vs. 38.5(25-55), p-value = 0.079) or in median post-meal state anxiety from hospital day 1 to 6 (35.5(29-56) vs. 37(24-56), p-value = 0.484). Similarly, we found minimal correlation between change in caloric intake and change in pre-meal S-anxiety (Spearman correlation coefficient = -0.032) or post-meal S-anxiety (Spearman correlation = 0.032). While this was a small sample observing anxiety over one week, we found no evidence that state anxiety increased with advancing calories, providing additional support for the use of more rapid refeeding protocols.

Mediation models of anxiety and depression between temperament and drive for thinness and body dissatisfaction in anorexia nervosa

PURPOSE

Anorexia nervosa (AN) is a life-threatening condition in which temperament, anxiety, depression, and core AN body-related psychopathology (drive for thinness, DT, and body dissatisfaction, BD) are intertwined. This relationship has not been to date disentangled; therefore, we performed a multiple mediation analysis aiming to quantify the effect of each component.

METHODS

An innovative multiple mediation statistical method has been applied to data from 184 inpatients with AN completing: Temperament Evaluation of Memphis, Pisa, Paris, and San Diego Autoquestionnaire, Eating Disorders Inventory-2, State-Trait Anxiety Inventory, and Beck Depression Inventory.

RESULTS

All affective temperaments but the hyperthymic one were involved in the relationship with DT and BD. Only the anxious temperament had a significant unmediated direct effect on DT after the strictest correction for multiple comparisons, while the depressive temperament had a significant direct effect on DT at a less strict significance level. State anxiety was the strongest mediator of the link between affective temperament and core AN body-related psychopathology. Depression showed intermediate results while trait anxiety was not a significant mediator at all.

CONCLUSION

Affective temperaments had a relevant impact on body-related core components of AN; however, a clear direct effect could be identified only for the anxious and depressive temperaments. Also, state anxiety was the strongest mediator thus entailing interesting implications in clinical practice.

LEVEL OF EVIDENCE

V, cross-sectional study.

In pursuit of biomarkers for predicting susceptibility to activity-based anorexia in adolescent female rats

OBJECTIVE

Identifying risk factors that contribute to the development of anorexia nervosa (AN) is critical for the implementation of early intervention strategies. Anxiety, obsessive-compulsive behavior, and immune dysfunction may be involved in the development of AN; however, their direct influence on susceptibility to the condition remains unclear. Here, we used the activity-based anorexia (ABA) model to examine whether activity, anxiety-like behavior, compulsive behavior, and circulating immune markers predict the subsequent development of pathological weight loss.

METHOD

Female Sprague-Dawley rats (n = 44) underwent behavioral testing before exposure to ABA conditions after which they were separated into susceptible and resistant subpopulations. Blood was sampled before behavioral testing and after recovery from ABA to screen for proinflammatory cytokines.

RESULTS

Rats that were vulnerable to pathological weight loss differed significantly from resistant rats on all key ABA parameters. While the primary measures of anxiety-like or compulsive behavior were not shown to predict vulnerability to ABA, increased locomotion and anxiety-like behavior were both associated with the extent of weight loss in susceptible but not resistant animals. Moreover, the change in expression of proinflammatory markers IL-4 and IL-6 evoked by ABA was associated with discrete vulnerability factors. Intriguingly, behavior related to risk assessment was shown to predict vulnerability to ABA.

DISCUSSION

We did not find undisputable behavioral or immune predictors of susceptibility to pathological weight loss in the ABA rat model. Future research should examine the role of cognition in the development of ABA, dysfunction of which may represent an endophenotype linking anorectic, anxiety-like and compulsive behavior.

PUBLIC SIGNIFICANCE

Anorexia nervosa (AN) has among the highest mortality rates of all psychiatric disorders and treatment options remain limited in their efficacy. Understanding what types of risk factors contribute to the development of AN is essential for implementing early intervention strategies. This study describes how some of the most common psychological features of AN could be used to predict susceptibility to pathological weight loss in a well-established animal model.

Emotional eating in women with generalized anxiety disorder

INTRODUCTION

Individuals diagnosed with generalized anxiety disorder (GAD) seek pleasurable foods to avoid their negative emotional experiences. Ineffective regulation of negative emotions may be a risk factor for emotional eating (EE), leading to suffering, dysfunctional behaviors, and weight gain.

OBJECTIVES

The aim of this study is to understand the relationship between emotional dysregulation and EE, investigating potential mediators such as the intensity of the worry, avoidance of internal experiences, mindfulness, and self-compassion in female patients with anxiety.

METHODS

In this cross-sectional study, participants from a randomized clinical trial diagnosed with GAD answered the following instruments at baseline: the Difficulties in Emotion Regulation Scale (DERS), the Three Factor Eating Questionnaire (TFEQ-R21), the Penn State Worry Questionnaire (PSWQ), the Action and Acceptance Questionnaire (AAQ), the Five Facet Mindfulness Questionnaire (FFMQ), and the Self-Compassion Scale (SCS). We estimated Pearson correlation coefficients and performed mediation analyses.

RESULTS

We evaluated 51 female individuals, 34 of whom completed all the questionnaires. Our data showed that EE was positively correlated with emotional dysregulation (r = 0.593; p < 0.001), worry trait (r = 0.402; p = 0.018), and avoidance of internal experiences (r = 0.565; p < 0.001), whereas it was negatively correlated with self-compassion (r = -0.590; p < 0.001) and mindful state (r = -0.383; p = 0.026). Moreover, we demonstrated that self-compassion mediates the relationship between emotional dysregulation and EE (ab product estimate = 0.043, 95% confidence interval [95%CI] 0.003-0.084).

CONCLUSION

Our findings contribute to the literature by identifying psychological factors that could mediate the association between emotional dysregulation and EE, enabling identification of more effective eating behavior intervention targets for patients with GAD.

Suppression of food restriction-evoked hyperactivity in activity-based anorexia animal model through glutamate transporters GLT-1 at excitatory synapses in the hippocampus

Severe voluntary food restriction is the defining symptom of anorexia nervosa (AN), but anxiety and excessive exercise are maladaptive symptoms that contribute significantly to the severity of AN and which individuals with AN have difficulty suppressing. We hypothesized that the excitability of hippocampal pyramidal neurons, known to contribute to anxiety, leads to the maladaptive behavior of excessive exercise. Conversely, since glutamate transporter GLT-1 dampens the excitability of hippocampal pyramidal neurons through the uptake of ambient glutamate and suppression of the GluN2B-subunit containing NMDA receptors (GluN2B-NMDARs), GLT-1 may contribute toward dampening excessive exercise. This hypothesis was tested using the mouse model of AN, called activity-based anorexia (ABA), whereby food restriction evokes the maladaptive behavior of excessive wheel running (food restriction-evoked running, FRER). We tested whether individual differences in ABA vulnerability of mice, quantified based on FRER, correlated with individual differences in the levels of GLT-1 at excitatory synapses of the hippocampus. Electron microscopic immunocytochemistry (EM-ICC) was used to quantify GLT-1 levels at the excitatory synapses of the hippocampus. The FRER seen in individual mice varied more than 10-fold, and Pearson correlation analyses revealed a strong negative correlation (p = .02) between FRER and GLT-1 levels at the axon terminals of excitatory synapses and at the surrounding astrocytic plasma membranes. Moreover, synaptic levels of GluN2B-NMDARs correlated strongly with GLT-1 levels at perisynaptic astrocytic plasma membranes. There is at present no accepted pharmacotherapy for AN, and little is known about the etiology of this deadly illness. Current findings suggest that drugs increasing GLT-1 expression may reduce AN severity through the reduction of GluN2B-NMDAR activity.

Effects of adolescent experience of food restriction and exercise on spatial learning and open field exploration of female rats

The hippocampus carries out multiple functions: spatial cognition dorsally (DH) and regulation of emotionality-driven behavior ventrally (VH). Previously, we showed that dendrites of DH and VH pyramidal neurons of female rats are still developing robustly during adolescence and are altered by the experience of food restriction and voluntary exercise on a wheel. We tested whether such anatomical changes during adolescence impact anxiety-like behavior and spatial cognition. Four groups of female rats were evaluated for these behaviors: those with wheel access in its cage from postnatal day (P) 36-44 (EX); those with food access restricted to 1 hr per day, from P40 to 44 (FR); those with EX from P36 to 44, combined with FR from P40 to 44, which we will refer to as EX + FR; and controls, CON (no EX, no FR). Open field test for anxiety-like behavior and active place avoidance test for spatial cognition were conducted at P47-49, the age when food restricted animals have restored body weight, or at P54-56, to identify more enduring effects. Anxiety-like behavior was elevated for the EX and FR groups at P47-49 but not for the EX + FR group. By P54-56, the EX + FR and EX groups exhibited less anxiety-like behavior, indicating a beneficial delayed main effect of exercise. There was a beneficial main effect of food restriction upon cognition, as the FR group showed cognition superior to CONs' at P44-46 and P54-56, while the EX + FR animals also showed enhanced spatial learning at P54-56. EX + FR animals with best adaptation to the feeding schedule showed the best spatial learning performance but with a delay. The EX group exhibited only a transient improvement. These findings indicate that FR, EX, and EX + FR in mid-adolescence are all beneficial in reducing anxiety-like behavior and improving spatial cognition but with subtle differences in the timing of their manifestation, possibly reflecting the protracted maturation of the hippocampus.

Affective temperaments and eating psychopathology in anorexia nervosa: Which role for anxious and depressive traits?

BACKGROUND

Anorexia nervosa (AN) is a severe mental illness. Personality traits and comorbidity with affective and anxiety disorders are key-aspects of its pathogenesis but little attention has been paid so far to affective temperaments in AN. Also, childhood anxiety is proposed to impact on AN clinical severity. Therefore, we aimed to investigate if affective temperaments could be related to AN eating psychopathology also clarifying if those with low versus high scores on depressive and anxious temperaments could differ in AN clinical current and lifetime severity.

METHODS

One-hundred and forty-seven inpatients with AN were consecutively recruited. All participants completed: Temperament Evaluation of Memphis, Pisa, Paris and San Diego-Autoquestionnaire, Eating Disorder Examination Questionnaire, State Trait Anxiety Inventory, Beck Depression Inventory. Clinical data were collected upon admission.

RESULTS

Regression models showed that all affective temperaments were associated with eating psychopathology (eating restraint and eating, shape, and weight concerns); however, when controlling for confounders, only the anxious temperament remained significant. Also, those patients with higher scores on depressive and anxious temperaments reported higher current and lowest lifetime body mass index (BMI).

LIMITATIONS

Only inpatients were recruited; self-report assessments were used and follow-up data are lacking.

CONCLUSIONS

Results from this study support the association between affective (anxious in particular) temperament traits and the presence of altered eating psychopathology in AN. Also, higher traits of depressive and anxious temperaments reported higher current and lowest lifetime BMI. Should these findings be confirmed, the assessment of the anxious temperament could fruitfully inform prevention and treatment interventions for AN.

Impulsivity influences food intake in women with generalized anxiety disorder

Objective:

Eating behavior is affected by psychological and neurocognitive factors. However, little is known about this relationship in anxious patients. Our aim was to investigate the associations between impulsivity, inhibitory control, energy-dense food consumption, and body mass index (BMI) in women with generalized anxiety disorder (GAD).

Methods:

In this cross-sectional study, 51 adult females with GAD answered the Barratt Impulsiveness Scale (BIS-11) and participated in a go/no-go task using food images. Anthropometric measurements were evaluated. A food frequency questionnaire and a snack test were used to study eating behavior. Pearson correlation and multiple linear regression were performed to analyze the variables of interest, adjusted by age.

Results:

Impulsivity predicted intake of sugar (p = 0.016, 95%CI 0.67-6.05), total fat (p = 0.007, 95%CI 0.62-3.71), and saturated fat (p = 0.004, 95%CI 0.30-1.48). The snack test showed a positive correlation between presence of impulsivity and intake of biscuits (R = 0.296; p = 0.051). Response inhibition to food images in the go/no-go task paradigm did not predict BMI or food intake.

Conclusion:

Impulsivity was predictive of higher sugar and saturated fat intake in women diagnosed with GAD. Our findings add to the literature regarding the association between neuropsychological factors and food consumption in this specific population.

Distorted weight perception correlates with disordered eating attitudes in Kuwaiti college women

OBJECTIVE

We investigated the presence of disordered eating attitudes and weight perception among young women at body mass index (BMI) values that correspond to underweight, normal weight, overweight, and obese weight status.

METHOD

Data were collected from 1,147 female undergraduate students (89% Kuwaiti nationals) recruited from Kuwait University through employment of the eating attitude test (EAT-26) together with an anonymous, self-administered questionnaire to determine the prevalence of symptomatology indicative of anorexia nervosa and bulimia nervosa.

RESULTS

The mean EAT-26 scores differed significantly between the weight categories. More students with overweight and obesity scored above the established EAT-26 cut off value indicating at risk of disordered eating compared to students who were at a normal weight or underweight (52.1% vs. 38.8%, respectively, X² (1) =16.1, p < .001). Logistic regression analyses showed significantly higher odds ratios (ORs) for the groups with overweight and obesity for dieting and bulimic behaviors, while women at normal and underweight had higher ORs for restrictive oral control behaviors associated with anorexia nervosa. Distorted weight perception was found in all weight categories.

DISCUSSION

The high proportion of disordered eating attitudes among Kuwaiti college women could not be attributed to obesity alone as the type of disordered eating behavior varied more by weight perception than by weight status. The high levels of eating disorder related symptoms could be due to a combination of the social influences, diet, and lifestyle of college students. Such factors need to be considered by healthcare professionals as early as possible with more focused programs towards promotion of healthy weight for college students.

Global/local processing style: Explaining the relationship between trait anxiety and binge eating

OBJECTIVE

Anxiety is a risk factor for disordered eating, but the mechanisms by which anxiety promotes disordered eating are poorly understood. One possibility is local versus global cognitive processing style, defined as a relative tendency to attend to details at the expense of the "big picture." Anxiety may narrow attention, in turn, enhancing local and/or compromising global processing. We examined relationships between global/local processing style, anxiety, and disordered eating behaviors in a transdiagnostic outpatient clinical sample. We hypothesized that local (vs. global) processing bias would mediate the relationship between anxiety and disordered eating behaviors.

METHOD

Ninety-three participants completed the eating disorder examination-questionnaire (EDE-Q), State-Trait Anxiety Inventory (STAI)-trait subscale, and the Navon task (a test of processing style in which large letters are composed of smaller letters both congruent and incongruent with the large letter). The sample was predominantly female (95%) with a mean age of 27.4 years (SD = 12.1 years).

RESULTS

Binge eating, but not fasting, purging, or excessive exercise, was correlated with lower levels of global processing style. There was a significant indirect effect between anxiety and binge eating via reduced global level global/local processing.

DISCUSSION

In individuals with disordered eating, being more generally anxious may encourage a detailed-oriented bias, preventing individuals from maintaining the bigger picture and making them more likely to engage in maladaptive behaviors (e.g., binge eating).

How extreme dieting becomes compulsive: A novel hypothesis for the role of anxiety in the development and maintenance of anorexia nervosa

The US National Institute of Mental Health's Research Domain Criteria (NIMH RDoC) advocates the study of features common to psychiatric conditions. This transdiagnostic approach has recently been adopted into the study of anorexia nervosa (AN), an illness that can be considered compulsive in nature. This has led to the development of an account of AN that identifies key roles for the heightened reinforcement of starvation, leading to its excessive repetition, and goal-directed system dysfunction. Considering models of illness in other compulsive disorders, we extend the existing account to explain the emergence of reinforcement and goal-directed system abnormalities in AN, proposing that anxiety is central to both processes. As such we emphasise the particular importance of the anxiolytic effects of starvation, over other reinforcing outcomes, in encouraging the continuation of starvation within a model that proposes a number of mechanisms by which anxiety operates in the development and maintenance of AN. We suggest the psychopathology of AN mediates the relationship between the anxiolytic effects of starvation and excessive repetition of starvation, and that compulsive starvation has reciprocal effects on its determinants. We thus account for the emergence of symptoms of AN other than compulsive starvation, and for the relationship between different features of the disorder. By extending and adapting an existing explanation of AN, we provide a richer aetiological model that invites new research questions and could inform novel approaches to prevention and treatment.

Affective temperaments in anorexia nervosa: The relevance of depressive and anxious traits

BACKGROUND

Affective temperaments have been so far understudied in anorexia nervosa (AN) despite the relevance of personality and both affective and anxious comorbidity with regard to vulnerability, course, and outcome of this deadly disorder.

METHODS

Ninety-eight female inpatients diagnosed with AN and 131 healthy controls (HCs) were enrolled in this study and completed the Temperament Evaluation of Memphis, Pisa, Paris and San Diego Autoquestionnaire (TEMPS-A) in addition to assessments of eating psychopathology, depression, and anxiety.

RESULTS

AN patients and HCs differed in all affective temperaments. The diagnostic subtypes of AN differed as well with binge-purging individuals being more cyclothymic and anxious than those with restricting-type AN. TEMPS-A scores correlated with body mass index and eating psychopathology but not with duration of illness. Concerning comorbidity, grater scores on the depressive and lower scores on the hyperthymic temperaments were found in depressed patients. Those who had either an anxious or irritable temperament were significantly more diagnosed with an anxious disorder than those who did not show this temperament. When logistic regression was performed, high depressive/low hyperthymic and high irritable/anxious traits resulted to be associated with depressive and anxious comorbidity, respectively, independently of confounding factors.

LIMITATIONS

Cross-sectional design, some patients on medications, few baseline clinical differences between diagnostic subtypes, no other personality assessments.

CONCLUSIONS

An affective continuum strongly associated with mood and anxious comorbidity emerged in AN. Such an evaluation could have several research and clinical implications given the need of improving treatment individualization and early interventions for such a complex disorder.

Treatment of anorexia nervosa: a multimethod investigation translating experimental neuroscience into clinical practice

Background

Anorexia nervosa (AN) is a severe psychiatric condition and evidence on how to best treat it is limited.

Objectives

This programme consists of seven integrated work packages (WPs) and aims to develop and test disseminable and cost-effective treatments to optimise management for people with AN across all stages of illness.

Methods

WP1a used surveys, focus groups and a pre–post trial to develop and evaluate a training programme for school staff on eating disorders (EDs). WP1b used a randomised controlled trial (RCT) [International Standard Randomised Controlled Trial Number (ISRCTN) 42594993] to evaluate a prevention programme for EDs in schools. WP2a evaluated an inpatient treatment for AN using case reports, interviews and a quasi-experimental trial. WP2b used a RCT (ISRCTN67720902) to evaluate two outpatient psychological therapies for AN. WP3 used a RCT (ISRCTN06149665) to evaluate an intervention for carers of inpatients with AN. WP4 used actimetry, self-report and endocrine assessment to examine physical activity (PA) in AN. WP5 conducted a RCT (ISRCTN18274621) of an e-mail-guided relapse prevention programme for inpatients with AN. WP6 analysed cohort data to examine the effects of maternal EDs on fertility and their children’s diet and growth. WP7a examined clinical case notes to explore how access to specialist ED services affects care pathways and user experiences. Finally, WP7b used data from this programme and the British Cohort Study (1970) to identify the costs of services used by people with AN and to estimate annual costs of AN for England.

Results

WP1a: a brief training programme improved knowledge, attitudes and confidence of school staff in managing EDs in school. WP1b: a teacher-delivered intervention was feasible and improved risk factors for EDs in adolescent girls. WP2a: both psychological therapies improved outcomes in outpatients with AN similarly, but patients preferred one of the treatments. WP2b: the inpatient treatment (Cognitive Remediation and Emotional Skills Training) was acceptable with perceived benefits by patients, but showed no benefits compared with treatment as usual (TAU). WP3: compared with TAU, the carer intervention improved a range of patient and carer outcomes, including carer burden and patient ED symptomatology. WP4: drive to exercise is tied to ED pathology and a desire to improve mood in AN patients. PA was not increased in these patients. WP5: compared with TAU, the e-mail-guided relapse prevention programme resulted in higher body mass index and lower distress in patients at 12 months after discharge. WP6: women with an ED had impaired fertility and their children had altered dietary and growth patterns compared with the children of women without an ED. WP7a: direct access to specialist ED services was associated with higher referral rates, lower admission rates, greater consistency of care and user satisfaction. WP7b: the annual costs of AN in England are estimated at between £45M and £230M for 2011.

Conclusions

This programme has produced evidence to inform future intervention development and has developed interventions that can be disseminated to improve outcomes for individuals with AN. Directions for future research include RCTs with longer-term outcomes and sufficient power to examine mediators and moderators of change.

Trial registration

Current Controlled Trials ISRCTN42594993, ISRCTN67720902, ISRCTN06149665 and ISRCTN18274621.

Funding

This project was funded by the National Institute for Health Research (NIHR) Programme Grants for Applied Research programme and will be published in full inProgramme Grants for Applied Research; Vol. 5, No. 16. See the NIHR Journals Library website for further project information.

A family-based association study of the HTR1B gene in eating disorders

Objective:

To explore the association of three polymorphisms of the serotonin receptor 1Dβ gene (HTR1B) in the etiology of eating disorders and their relationship with clinical characteristics.

Methods:

We analyzed the G861C, A-161T, and A1180G polymorphisms of the HTR1B gene through a family-based association test (FBAT) in 245 nuclear families. The sample was stratified into anorexia nervosa (AN) spectrum and bulimia nervosa (BN) spectrum. In addition, we performed a quantitative FBAT analysis of anxiety severity, depression severity, and Yale-Brown-Cornell Eating Disorders Scale (YBC-EDS) in the AN and BN-spectrum groups.

Results:

FBAT analysis of the A-161T polymorphism found preferential transmission of allele A-161 in the overall sample. This association was stronger when the sample was stratified by spectrums, showing transmission disequilibrium between the A-161 allele and BN spectrum (z = 2.871, p = 0.004). Quantitative trait analysis showed an association between severity of anxiety symptoms and the C861 allele in AN-spectrum participants (z = 2.871, p = 0.004). We found no associations on analysis of depression severity or preoccupation and ritual scores in AN or BN-spectrum participants.

Conclusions:

Our preliminary findings suggest a role of the HTR1B gene in susceptibility to development of BN subtypes. Furthermore, this gene might have an impact on the severity of anxiety in AN-spectrum patients.

Disorder-specific patterns of emotion coregulation in couples: Comparing obsessive compulsive disorder and anorexia nervosa

Impaired emotion regulation and maladaptive strategies to manage distress are central to psychopathology, including obsessive-compulsive disorder (OCD) and anorexia nervosa (AN). Emotion regulation can be fostered or thwarted by romantic partners, and the tendency to rely on interpersonally oriented emotion regulation may vary by disorder. This study examined coregulation as a form of interpersonal emotion regulation in OCD and AN. We hypothesized that OCD is associated with exaggerated and AN with diminished coregulation, and that OCD patients have greater overall levels of emotional arousal than AN patients. Greater symptom severity was expected to exacerbate these opposing tendencies. Vocally encoded emotional arousal was measured during couple conversations in 34 AN patients, 18 OCD patients, and their partners. Two indicators of coregulation (covariation and coupling) were analyzed using cross-lagged actor-partner interdependence and coupled linear oscillator models. As hypothesized, OCD was associated with greater overall emotional arousal than AN. Symptom severity was not associated with emotional arousal or coregulation. Covariation differed in the opposite direction of the hypothesis; there was no difference in coupling. AN patients exhibited consistent coregulation, indicating high reactivity to partners' emotional arousal which may contribute to interpersonal avoidance. OCD couples showed limited predictability of patients' arousal over time, while partners were affected by the patients' emotional arousal; thus, symptom accommodation may in part be partners' attempts at managing their own distress along with the patients'. A better understanding of interpersonal emotion regulation in OCD and AN can inform treatment by targeting interaction patterns that may maintain symptoms. (PsycINFO Database Record

Synaptic changes in the hippocampus of adolescent female rodents associated with resilience to anxiety and suppression of food restriction-evoked hyperactivity in an animal model for anorexia nervosa

Anorexia nervosa is a mental illness that emerges primarily during early adolescence, with mortality rate that is 200 times higher than that of suicide. The illness is characterized by intense fear of gaining weight, heightened anxiety, obstinate food restriction, often accompanied by excessive exercise, in spite of mounting hunger. The illness affects females nine times more often than males, suggesting an endocrine role in its etiology. Its relapse rate exceeds 25%, yet there are no accepted pharmacological treatments to prevent this. Here, we summarize studies from this laboratory that have used adolescent female rodents in activity-based anorexia (ABA), an animal model of anorexia nervosa, with the goal of identifying neurobiological underpinnings of this disease. We put forth a hypothesis that a GABAergic mechanism within the hippocampus is central to regulating an individual׳s anxiety which, in turn, strongly influences the individual׳s resilience/vulnerability to ABA. In particular, we propose that ionotropic GABAA receptors containing the subunits alpha4 and delta, are at play for exerting shunting inhibition upon hippocampal pyramidal neurons that become more excitable during ABA. Since these receptors confer insensitivity to benzodiazepines, this pharmacological profile of ABA fits with lack of report indicating efficacy of benzodiazepines in reducing the anxiety experienced by individuals with anorexia nervosa. The idea that the GABAergic system of the hippocampus regulates resilience/vulnerability to anorexia nervosa complements current opinions about the important roles of the prefrontal cortex, amygdala, striatum, gustatory pathways and feeding centers of the hypothalamus and of the neuromodulators, serotonin and dopamine, in the etiology of the disease. This article is part of a Special Issue entitled SI: Adolescent plasticity.

BDNF-Val66Met variant and adolescent stress interact to promote susceptibility to anorexic behavior in mice

There is an urgent need to identify therapeutic targets for anorexia nervosa (AN) because current medications do not impact eating behaviors that drive AN's high mortality rate. A major obstacle to developing new treatments is the lack of animal models that recapitulate the pattern of disease onset typically observed in human populations. Here we describe a translational mouse model to study interactions between genetic, psychological and biological risk factors that promote anorexic behavior. We combined several factors that are consistently associated with increased risk of AN-adolescent females, genetic predisposition to anxiety imposed by the BDNF-Val66Met gene variant, social isolation stress and caloric restriction (CR). Approximately 40% of the mice with all of these risk factors will exhibit severe self-imposed dietary restriction, sometimes to the point of death. We systematically varied the risk factors outlined above to explore how they interact to influence anorexic behavior. We found that the Val66Met genotype markedly increases the likelihood and severity of abnormal feeding behavior triggered by CR, but only when CR is imposed in the peri-pubertal period. Incidence of anorexic behavior in our model is dependent on juvenile exposure to social stress and can be extinguished by adolescent handling, but is discordant from anxiety-like behavior. Thus, this study characterized gene × environment interactions during adolescence that could be the underlying driver of abnormal eating behavior in certain AN patients, and represents a promising system to identify possible targets for therapeutic intervention.

Altered SPECT (123)I-iomazenil Binding in the Cingulate Cortex of Children with Anorexia Nervosa

Several lines of evidence suggest that anxiety plays a key role in the development and maintenance of anorexia nervosa (AN) in children. The purpose of this study was to examine cortical GABA(A)-benzodiazepine receptor binding before and after treatment in children beginning intensive AN treatment. Brain single-photon emission computed tomography (SPECT) measurements using (123)I-iomazenil, which binds to GABA(A)-benzodiazepine receptors, was performed in 26 participants with AN who were enrolled in a multimodal treatment program. Sixteen of the 26 participants underwent a repeat SPECT scan immediately before discharge at conclusion of the intensive treatment program. Eating behavior and mood disturbances were assessed using Eating Attitudes Test with 26 items (EAT-26) and the short form of the Profile of Mood States (POMS). Clinical outcome scores were evaluated after a 1-year period. We examined association between relative iomazenil-binding activity in cortical regions of interest and psychometric profiles and determined which psychometric profiles show interaction effects with brain regions. Further, we determined if binding activity could predict clinical outcome and treatment changes. Higher EAT-26 scores were significantly associated with lower iomazenil-binding activity in the anterior and posterior cingulate cortex. Higher POMS subscale scores were significantly associated with lower iomazenil-binding activity in the left frontal, parietal cortex, and posterior cingulate cortex (PCC). "Depression-Dejection" and "Confusion" POMS subscale scores, and total POMS score showed interaction effects with brain regions in iomazenil-binding activity. Decreased binding in the anterior cingulate cortex and left parietal cortex was associated with poor clinical outcomes. Relative binding increases throughout the PCC and occipital gyrus were observed after weight gain in children with AN. These findings suggest that cortical GABAergic receptor binding is altered in children with AN. This may be a state-related change, which could be used to monitor and guide the treatment of eating disorders.

Enlargement of Axo-Somatic Contacts Formed by GAD-Immunoreactive Axon Terminals onto Layer V Pyramidal Neurons in the Medial Prefrontal Cortex of Adolescent Female Mice Is Associated with Suppression of Food Restriction-Evoked Hyperactivity and Resilience to Activity-Based Anorexia

Many, but not all, adolescent female mice that are exposed to a running wheel while food restricted (FR) become excessive wheel runners, choosing to run even during the hours of food availability, to the point of death. This phenomenon is called activity-based anorexia (ABA). We used electron microscopic immunocytochemistry to ask whether individual differences in ABA resilience may correlate with the lengths of axo-somatic contacts made by GABAergic axon terminals onto layer 5 pyramidal neurons (L5P) in the prefrontal cortex. Contact lengths were, on average, 40% greater for the ABA-induced mice, relative to controls. Correspondingly, the proportion of L5P perikaryal plasma membrane contacted by GABAergic terminals was 45% greater for the ABA mice. Contact lengths in the anterior cingulate cortex correlated negatively and strongly with the overall wheel activity after FR (R = -0.87, P < 0.01), whereas those in the prelimbic cortex correlated negatively with wheel running specifically during the hours of food availability of the FR days (R = -0.84, P < 0.05). These negative correlations support the idea that increases in the glutamic acid decarboxylase (GAD) terminal contact lengths onto L5P contribute toward ABA resilience through suppression of wheel running, a behavior that is intrinsically rewarding and helpful for foraging but maladaptive within a cage.

Anorexia nervosa as a motivated behavior: Relevance of anxiety, stress, fear and learning

The high comorbidity between anorexia nervosa (AN) and anxiety disorders is well recognized. AN is a motivated behavioral disorder in which habit formation is likely to contribute to the persistence of abnormal eating and exercise behaviors. Secondary alterations in brain circuitry underlying the reward value of food and exercise, along with disturbances in neuroendocrine hunger and satiety signaling arising from starvation and excessive exercise, are likely contributors to the maintenance of anorectic behaviors in genetically vulnerable individuals. The potential role of fear conditioning in facilitating onset of AN, or of impaired fear extinction in contributing to the high relapse rates observed following weight restoration, is of interest. Evidence from animal models of anxiety and human laboratory studies indicate that low estrogen impairs fear extinction. Low estradiol levels in AN may therefore play a role in perpetuating fear of food and fat in recently weight restored patients. Translational models including the activity based anorexia (ABA) rodent model of AN, and neuroimaging studies of fear extinction and conditioning, could help clarify the underlying molecular mechanisms and neurocircuitry involved in food avoidance behaviors in AN. Moreover, the adaptation of novel treatment interventions with efficacy in anxiety disorders may contribute to the development of new treatments for this impairing disorder.

Does anxiety improve during weight restoration in anorexia nervosa? A systematic review

Weight restoration is considered a principal outcome for treatment of Anorexia Nervosa (AN) due to the significant physiological disturbances resultant from acute states of malnutrition. Treatment outcomes for populations with AN are relatively poor, with increasing evidence suggesting that weight restoration alone is insufficient for long-term recovery. Research aimed at understanding the psychological sequaele of AN, in particular during weight restoration, nevertheless remain scarce. This systematic review aimed to evaluate existing research regarding anxiety symptoms during treatment for AN, and the relationship of anxiety symptomology and weight restoration. Twelve articles were identified from a systematic search of three electronic databases (PsycINFO, MEDLINE, and Web of Science), and were eligible for inclusion. Study methodology, results and quality were reviewed. Results regarding change in anxiety symptomology were inconsistent, though evidence did not support a relationship between anxiety change and weight restoration. Reasons for these inconsistencies and limitations of included studies were reviewed. Further research is warranted to elucidate the role of anxiety in AN and its implications for treatment and longer-term outcome.

Physical activity and the drive to exercise in anorexia nervosa

OBJECTIVES

To investigate physical activity (PA) and drive for exercise in anorexia nervosa (AN) in relation to eating disorder (ED) pathology and anxiety.

METHOD

Female participants were recruited into four groups: AN outpatients (n = 37), AN inpatients (n = 18), an anxiety group (n = 34), and healthy controls (HCs; n = 30). PA was measured by actigraphy and self-report together with drive/reasons for exercise, ED pathology, anxiety, depression, stress, BMI, and body composition.

RESULTS

ED psychopathology, general psychopathology, and physiological measures were consistent with diagnosis. All groups showed a wide range in activity, especially on self-report. No significant group differences were observed in objective PA levels, yet AN groups reported 57-92% higher total activity than HCs. Outpatients reported more walking and moderate exercise than HCs, and inpatients reported more walking but less moderate and vigorous activity than all other groups. AN groups had significantly higher drive to exercise and valued "improving tone" as important and health and enjoyment as less important reasons to exercise.

DISCUSSION

Self-perceived activity rather than objective data may partly explain the increased activity reported in AN. Drive to exercise in AN appears to be more related to ED pathology than to anxiety.

The plasticity of development: how knowledge of epigenetics may advance understanding of eating disorders

OBJECTIVE

To depict the processes through which animals and human beings engage their environment in continuously evolving states of conflict and cooperation.

METHOD

Descriptive literature review.

RESULTS

Life history outcomes are more relative than they are absolute. Genetic variations play a crucial role, but heavily influencing behavioral outcomes, psychopathology included, are external cues that epigenetically remodel DNA along experience-dependent signaling pathways. The result is phenotypes that either optimize adjustment, or constrain it.

DISCUSSION

Knowledge of epigenetic mechanisms may help shed new light on the origin of maturational phenotypes underlying eating disorders and why adjusting treatments to these realities warrants our attention.

The role of leptin, melanocortin, and neurotrophin system genes on body weight in anorexia nervosa and bulimia nervosa

OBJECTIVE

Although low weight is a key factor contributing to the high mortality in anorexia nervosa (AN), it is unclear how AN patients sustain low weight compared with bulimia nervosa (BN) patients with similar psychopathology. Studies of genes involved in appetite and weight regulation in eating disorders have yielded variable findings, in part due to small sample size and clinical heterogeneity. This study: (1) assessed the role of leptin, melanocortin, and neurotrophin genetic variants in conferring risk for AN and BN; and (2) explored the involvement of these genes in body mass index (BMI) variations within AN and BN.

METHOD

Our sample consisted of 745 individuals with AN without a history of BN, 245 individuals with BN without a history of AN, and 321 controls. We genotyped 20 markers with known or putative function among genes selected from leptin, melanocortin, and neurotrophin systems.

RESULTS

There were no significant differences in allele frequencies among individuals with AN, BN, and controls. AGRP rs13338499 polymorphism was associated with lowest illness-related BMI in those with AN (p = 0.0013), and NTRK2 rs1042571 was associated with highest BMI in those with BN (p = 0.0018).

DISCUSSION

To our knowledge, this is the first study to address the issue of clinical heterogeneity in eating disorder genetic research and to explore the role of known or putatively functional markers in genes regulating appetite and weight in individuals with AN and BN. If replicated, our results may serve as an important first step toward gaining a better understanding of weight regulation in eating disorders.

Childhood obsessive-compulsive traits in anorexia nervosa patients, their unaffected sisters and healthy controls: a retrospective study

Although there is evidence that childhood perfectionistic traits predate the onset of eating disorders, few studies to date have examined the prevalence and clinical correlates of these traits in patients with anorexia nervosa (AN) and their unaffected sisters. The aim of this work was to study the prevalence of childhood obsessive-compulsive traits in patients with lifetime AN, their unaffected sisters and healthy women. A total of 116 AN patients, 32 healthy sisters and 119 controls were assessed by the EATATE Interview to assess traits such as perfectionism, inflexibility, rule-bound traits, drive for order and symmetry, and excessive doubt and cautiousness. Both self-report and maternal reports were collected. AN patients reported more childhood obsessive-compulsive traits than their healthy sisters and controls. In contrast, no differences between healthy controls and unaffected sisters emerged. In patients with AN, a dose-response relationship was found between the number of childhood obsessive-compulsive traits and psychopathology, including body image distortion, thus indicating that these traits are an important feature to be considered in assessing and treating eating disorders.

α4βδ-GABAARs in the hippocampal CA1 as a biomarker for resilience to activity-based anorexia

Anorexia nervosa (AN) is a psychiatric illness characterized by restricted eating and an intense fear of gaining weight. Most individuals with AN are females, diagnosed first during adolescence, 40-80% of whom exhibit excessive exercise, and an equally high number with a history of anxiety disorder. We sought to determine the cellular basis for individual differences in AN vulnerability by using an animal model, activity-based anorexia (ABA), that is induced by combining food restriction (FR) with access to a running wheel that allows voluntary exercise. Previously, we showed that by the fourth day of FR, the ABA group of adolescent female rats exhibit >500% greater levels of non-synaptic α4βδ-GABAARs at the plasma membrane of hippocampal CA1 pyramidal cell spines, relative to the levels found in age-matched controls that are not FR and without wheel access. Here, we show that the ABA group exhibits individual differences in body weight loss, with some losing nearly 30%, while others lose only 15%. The individual differences in weight loss are ascribable to individual differences in wheel activity that both precedes and concurs with days of FR. Moreover, the increase in activity during FR correlates strongly and negatively with α4βδ-GABAAR levels (R=-0.9, p<0.01). This negative correlation is evident within 2days of FR, before body weight loss approaches life-threatening levels for any individual. These findings suggest that increased shunting inhibition by α4βδ-GABAARs in spines of CA1 pyramidal neurons may participate in the protection against the ABA-inducing environmental factors of severe weight loss by suppressing excitability of the CA1 pyramidal neurons which, in turn, is related indirectly to suppression of excessive exercise. The data also indicate that, although exercise has many health benefits, it can be maladaptive to individuals with low levels of α4βδ-GABAARs in the CA1, particularly when combined with FR.

Threat-related attentional bias in anorexia nervosa

OBJECTIVE

Attentional bias (AB) modification treatment targeting general or social anxiety has been recently highlighted as a potential novel approach for the treatment of anorexia nervosa (AN). The purpose of this study was to examine threat-related AB in patients with ANand healthy control participants (HC) and the relationship between AB and eating disorder and other psychopathology.

METHOD

Forty-nine female outpatients with AN or Eating Disorder Not Otherwise Specified, Anorexia Type (EDNOS-AN), and 44 female HC completed a dot-probe task with threat words and a range of self-report measures assessing eating disorder symptoms and other psychopathology.

RESULTS

There was no evidence for a differential threat-related AB in AN patients despite elevated anxiety in this group. The AB-index, a parameter of the magnitude of attention allocation when two competing stimuli are presented, did not correlate with any of the self-report measures. However, patients with AN responded significantly more slowly to the probe as compared to controls, regardless of the valence or position of the stimuli.

DISCUSSION

The results suggest that the AB in AN patients may be specific to eating disorder-relevant anxieties.

Altered brain reward circuits in eating disorders: chicken or egg?

The eating disorders anorexia nervosa (AN) and bulimia nervosa (BN) are severe psychiatric disorders with high mortality. Our knowledge about the neurobiology of eating disorders is very limited, and the question remains whether alterations in brain structure or function in eating disorders are state related, remnants of the illness or premorbid traits. The brain reward system is a relatively well-characterized brain circuitry that plays a central role in the drive to eat and individuals with current or past eating disorders showed alterations in those pathways compared to controls. Here we propose that structural and functional alterations in the insula and frontal cortex, including orbitofrontal and cingulate regions, areas that contribute to reward and anxiety processing, could predispose to developing an eating disorder and that adaptive changes in those circuits in response to malnutrition or repeated binge eating and purging could further promote illness behavior, hinder recovery and contribute to relapse.

Factors associated with recovery from anorexia nervosa

Previous studies of prognostic factors of anorexia nervosa (AN) course and recovery have followed clinical populations after treatment discharge. This retrospective study examined the association between prognostic factors--eating disorder features, personality traits, and psychiatric comorbidity--and likelihood of recovery in a large sample of women with AN participating in a multi-site genetic study. The study included 680 women with AN. Recovery was defined as the offset of AN symptoms if the participant experienced at least one year without any eating disorder symptoms of low weight, dieting, binge eating, and inappropriate compensatory behaviors. Participants completed a structured interview about eating disorders features, psychiatric comorbidity, and self-report measures of personality. Survival analysis was applied to model time to recovery from AN. Cox regression models were used to fit associations between predictors and the probability of recovery. In the final model, likelihood of recovery was significantly predicted by the following prognostic factors: vomiting, impulsivity, and trait anxiety. Self-induced vomiting and greater trait anxiety were negative prognostic factors and predicted lower likelihood of recovery. Greater impulsivity was a positive prognostic factor and predicted greater likelihood of recovery. There was a significant interaction between impulsivity and time; the association between impulsivity and likelihood of recovery decreased as duration of AN increased. The anxiolytic function of some AN behaviors may impede recovery for individuals with greater trait anxiety.

Nothing tastes as good as skinny feels: the neurobiology of anorexia nervosa

Individuals with anorexia nervosa (AN) engage in relentless restrictive eating and often become severely emaciated. Because there are no proven treatments, AN has high rates of relapse, chronicity, and death. Those with AN tend to have childhood temperament and personality traits, such as anxiety, obsessions, and perfectionism, which may reflect neurobiological risk factors for developing AN. Restricted eating may be a means of reducing negative mood caused by skewed interactions between serotonin aversive or inhibitory and dopamine reward systems. Brain imaging studies suggest that altered eating is a consequence of dysregulated reward and/or awareness of homeostatic needs, perhaps related to enhanced executive ability to inhibit incentive motivational drives. An understanding of the neurobiology of this disorder is likely to be important for developing more effective treatments.

Early life nutrient restriction impairs blood-brain metabolic profile and neurobehavior predisposing to Alzheimer's disease with aging

Prenatal nutrient restriction (NR) culminating in intra-uterine growth restriction (IUGR) with postnatal catch up growth leads to diabesity. In contrast, postnatal NR with growth restriction (PNGR) superimposed on IUGR (IPGR) protects young and aging adults from this phenotype. We hypothesized that PNGR/IPGR will compromise the blood-brain metabolic profile impairing neurobehavior and predisposing to Alzheimer's disease (AD). NR (50%) in late gestation followed by cross-fostering of rat pups to either ad lib fed (CON) or NR (50%) lactating mothers generated CON, IUGR, PNGR and IPGR male (M) and female (F) offspring that were examined through the life span. In PNGR/IPGR plasma/CSF glucose and lactate decreased while ketones increased in (M) and (F) (PN21, PN50). In addition increased brain glucose transporters, Glut1 & Glut3, greater brain derived neurotrophic factor (BDNF), reduced Glut4, with unchanged serotonin transporter concentrations were noted in (F) (PN50-60). While (F) displayed more hyperactivity, both (F) and (M) exhibited anxiety although socially and cognitively unimpaired (PN25-28&50). Aging (15-17 m) (F) not (M), expressed low plasma insulin, reduced brain IRS-2, pAkt, and pGSK-3β(Ser9), unchanged pPDK1, pTau or lipoprotein receptor related protein 1 (LRP1), higher glial fibrillary acidic protein (GFAP) and spinophilin but a 10-fold increased amyloid-β42. We conclude that therapeutically superimposing PNGR on IUGR (IPGR) should be carefully weighed in light of unintended consequences related to perturbed neurobehavior and potential predilection for AD.

Genetic association of recovery from eating disorders: the role of GABA receptor SNPs

Follow-up studies of eating disorders (EDs) suggest outcomes ranging from recovery to chronic illness or death, but predictors of outcome have not been consistently identified. We tested 5151 single-nucleotide polymorphisms (SNPs) in approximately 350 candidate genes for association with recovery from ED in 1878 women. Initial analyses focused on a strictly defined discovery cohort of women who were over age 25 years, carried a lifetime diagnosis of an ED, and for whom data were available regarding the presence (n=361 ongoing symptoms in the past year, ie, 'ill') or absence (n=115 no symptoms in the past year, ie, 'recovered') of ED symptoms. An intronic SNP (rs17536211) in GABRG1 showed the strongest statistical evidence of association (p=4.63 × 10(-6), false discovery rate (FDR)=0.021, odds ratio (OR)=0.46). We replicated these findings in a more liberally defined cohort of women age 25 years or younger (n=464 ill, n=107 recovered; p=0.0336, OR=0.68; combined sample p=4.57 × 10(-6), FDR=0.0049, OR=0.55). Enrichment analyses revealed that GABA (γ-aminobutyric acid) SNPs were over-represented among SNPs associated at p<0.05 in both the discovery (Z=3.64, p=0.0003) and combined cohorts (Z=2.07, p=0.0388). In follow-up phenomic association analyses with a third independent cohort (n=154 ED cases, n=677 controls), rs17536211 was associated with trait anxiety (p=0.049), suggesting a possible mechanism through which this variant may influence ED outcome. These findings could provide new insights into the development of more effective interventions for the most treatment-resistant patients.

A meta-analysis of circulating BDNF concentrations in anorexia nervosa

OBJECTIVES

Brain derived neurotrophic factor (BDNF) is involved in neuroplasticity, and in the homeostatic regulation of food intake and energy expenditure. It also has a role in stress responsivity and reward processing. On the basis of its involvement in these various processes, BDNF can be hypothesized to be an important factor in the development and maintenance of anorexia nervosa (AN). This study meta-analytically summarizes investigations of serum BDNF concentrations in people currently ill with AN, in comparison to healthy controls.

METHODS

Seven studies measuring BDNF in serum of individuals with AN (n=155) and healthy controls (n=174) were identified and included in the meta-analysis of the mean differences between case and control groups.

RESULTS

This study confirms that AN is associated with decreased serum BDNF concentrations, in comparison to healthy controls. The combined effect size (standardized mean difference, SMD) was large (SMD=-0.96; 95% CI -1.33 to -0.59; P<0.001). Significant heterogeneity of effect sizes was identified (I(2)=58.3%; P<0.001), which emerged as being primarily attributable to the first published study on the investigated association.

CONCLUSIONS

The present meta-analytical summary of studies measuring circulating BDNF concentrations in women with AN and healthy controls confirms that it is significantly reduced in this patient group. Difficulties associated with the measurement of BDNF have been identified and potential confounding factors have been discussed. Current data do not allow inferences to be made about causal links between levels of circulating BDNF and AN. However, possible explanations for the relationship between BDNF and AN have been presented.

An experimental exploration of behavioral and cognitive-emotional aspects of intolerance of uncertainty in eating disorder patients

OBJECTIVE

Intolerance of uncertainty (IU) is an important concept in eating disorders (ED). Cognitive, emotional, and behavioral features of IU amongst individuals with and without ED were investigated.

METHOD

Participants completed the intolerance of uncertainty scale (IUS) and four versions of a data-gathering task varying in difficulty/uncertainty, and rated their Beads task experience.

RESULTS

ED groups had significantly higher IUS scores than healthy controls (HC). Bulimia Nervosa (BN) participants requested more cues than HC and Anorexia Nervosa (AN) participants before making decisions. ED groups found the task more distressing than HC participants, with those with BN feeling more uncertain and less confident in their decisions, and those with AN attributing greater importance in making the correct decision.

DISCUSSION

While both ED groups reported raised IUS scores only BN participants engaged in an elevated evidence requirement data gathering style. Future research might benefit from further exploration of the role of perseverative processes in BN.

Generalized anxiety disorder and anorexia nervosa: evidence of shared genetic variation

BACKGROUND

Previous studies have indicated a high prevalence of generalized anxiety disorder (GAD) in women with anorexia nervosa (AN). However, the shared genetic and environmental components of these disorders have not been explored. This study seeks to elucidate the shared genetic and environmental components between GAD and AN.

METHOD

Using 2,083 women from the Virginia Adult Twin Study of Psychiatric and Substance Use Disorders, structural equation modeling was used to obtain maximum likelihood estimates of the environmental genetic, shared and unique environmental components in 496 women with GAD, 47 women with AN, 43 women with GAD + AN, and 1,497 women without GAD or AN.

RESULTS

Results show that the heritability of GAD was 0.32 and AN was 0.31, and the genetic correlation between the two disorders was 0.20, indicating a modest genetic contribution to their comorbidity. Unique environment estimate was 0.68 for GAD and 0.69 for AN, with a unique environmental correlation of 0.18. All common environmental parameters were estimated at zero.

CONCLUSIONS

The modest shared genetic and unique environmental liability to both disorders may help explain the high prevalence of GAD in women with AN. This knowledge could help in the treatment and prevention of comorbid disorders.

The effect of Pilates exercises on body composition: a systematic review

OBJECTIVE

The purpose of this systematic review was to determine how Pilates exercises have impacted body composition (BC) on selected populations.

METHODS

A comprehensive literature search was performed using the keywords 'Pilates, body composition, systematic review, literature review, overweight, obesity, healthy weight, underweight' and their combination.

RESULTS

Seven studies met the inclusion criteria and after further quality analyses it was determined that there is currently poor empirical quantitative evidence indicating a positive effect of Pilates exercises on BC. Several methodological flaws were observed in the studies analyzed, including few full-text published studies looking into the effects of Pilates exercises on BC, a lack of true experimental research designs, limited standardization in measurement techniques, insufficient or no control of the nutritional status, and inconsistent instructor qualifications.

CONCLUSION

Well-designed research is needed to determine how Pilates exercises impact BC on selected populations.

Anorexia nervosa and generalized anxiety disorder: further explorations of the relation between anxiety and body mass index

We explore comorbidity of anorexia nervosa (AN) and generalized anxiety disorder (GAD) and their relation with body mass index (BMI) and evaluate the presence of fasting and excessive exercise which both have anxiolytic and weight loss effects. All participants were female: 32 with AN only, 607 with GAD only, 22 with AN and GAD (AN+GAD), and 5424 with no history of AN or GAD (referent) from the Swedish Twin study of Adults: Genes and Environment (STAGE). Lowest adult BMI differed significantly (p<.001) and was lower in those with AN+GAD than those with AN only (p<.029). Those with AN+GAD were most likely to endorse fasting and excessive exercise, followed by women with AN only, women with GAD only, and the referent. Comorbid AN and GAD may be a particularly pernicious presentation influencing both BMI and proclivity to engage in behaviors such as fasting and exercise that serve both weight loss and anxiolytic goals.

Impact of broadening definitions of anorexia nervosa on sample characteristics

Practical limitations and sample size considerations often lead to broadening of diagnostic criteria for anorexia nervosa (AN) in research. The current study sought to elucidate the effects of this practice on resultant sample characteristics in terms of eating disorder behaviors, psychiatric comorbidities, temperament and personality characteristics, and heritability point estimates. Three definitions of AN were created: meeting all Diagnostic and Statistical Manual of Mental Disorders-IV (DSM-IV) criteria for AN (AN-DSM-IV), meeting all DSM-IV criteria except criterion D, amenorrhea, (AN-noD), and broadening DSM-IV AN criteria by allowing a higher body mass index value, eliminating criterion D, and allowing less stringent body weight concerns (AN-Broad). Using data from the Swedish Twin Registry, 473 women fit one of the three definitions of AN. Women with AN-DSM-IV reported significantly more eating disorder behaviors than women with AN-Broad. Women with AN-noD reported more comorbid psychiatric disorders than women with AN-DSM-IV and AN-Broad. Temperament and personality characteristics did not differ across the three groups. Heritability point estimates decreased as AN definition broadened. Broadening the diagnostic criteria for AN results in an increased number of individuals available for participation in research studies. However, broader criteria for AN yield a more heterogeneous sample with regard to eating disorder symptoms and psychiatric comorbidity than a sample defined by narrower criteria.