Drug abuse in women with eating disorders

Use of glucagon-like peptide-1 receptor agonists in eating disorder populations

Glucagon-like peptide-1 receptor agonists (GLP-1As) are being used as approved or off-label treatments for weight loss. As such, there has been increasing concern about the potential for GLP-1As to impact eating disorder (ED) symptomatology. This article seeks to (1) review the current state of knowledge regarding GLP-1As and ED symptomatology; (2) provide recommendations for future research; and (3) guide ED clinicians in how to discuss GLP-1As in clinical practice. Although evidence is limited, it is possible that GLP-1As could exacerbate, or contribute to the development of, ED pathology and negatively impact ED treatment. Preliminary research on the use of GLP-1As to treat binge eating has been conducted; however, studies have design limitations and additional research is needed. Therefore, at the current time there is not sufficient evidence to support the use of GLP-1s to treat ED symptoms. In summary, more research is required before negative or positive conclusions can be drawn about the impact of GLP-1As on EDs psychopathology. Herein, we provide specific recommendations for future research and a guide to help clinicians navigate discussions with their clients about GLP-1As. A client handout is also provided. PUBLIC SIGNIFICANCE: Despite glucagon-like peptide-1 receptor agonists (GLP-1As; e.g., semaglutide) increasingly being the topic of clinical and public discourse, little is known about their potential impact on ED symptoms. It is possible that GLP-1As could maintain, worsen, or improve ED symptoms. This article reviews the limited literature on GLP-1As and ED symptoms, recommends future research, and provides clinicians with a guide for discussing GLP-1As with ED clients.

Lateral hypothalamus hypocretin/orexin glucose-inhibited neurons promote food seeking after calorie restriction

OBJECTIVE

The present study tests the hypothesis that changes in the glucose sensitivity of lateral hypothalamus (LH) hypocretin/orexin glucose-inhibited (GI) neurons following weight loss leads to glutamate plasticity on ventral tegmental area (VTA) dopamine neurons and drives food seeking behavior.

METHODS

C57BL/6J mice were calorie restricted to a 15% body weight loss and maintained at that body weight for 1 week. The glucose sensitivity of LH hypocretin/orexin GI and VTA dopamine neurons was measured using whole cell patch clamp recordings in brain slices. Food seeking behavior was assessed using conditioned place preference (CPP).

RESULTS

1-week maintenance of calorie restricted 15% body weight loss reduced glucose inhibition of hypocretin/orexin GI neurons resulting in increased neuronal activation with reduced glycemia. The effect of decreased glucose on hypocretin/orexin GI neuronal activation was blocked by pertussis toxin (inhibitor of G-protein coupled receptor subunit Gαi/o) and Rp-cAMP (inhibitor of protein kinase A, PKA). This suggests that glucose sensitivity is mediated by the Gαi/o-adenylyl cyclase-cAMP-PKA signaling pathway. The excitatory effect of the hunger hormone, ghrelin, on hcrt/ox neurons was also blocked by Rp-cAMP suggesting that hormonal signals of metabolic status may converge on the glucose sensing pathway. Food restriction and weight loss increased glutamate synaptic strength (indexed by increased AMPA/NMDA receptor current ratio) on VTA dopamine neurons and the motivation to seek food (indexed by CPP). Chemogenetic inhibition of hypocretin/orexin neurons during caloric restriction and weight loss prevented these changes in glutamate plasticity and food seeking behavior.

CONCLUSIONS

We hypothesize that this change in the glucose sensitivity of hypocretin/orexin GI neurons may drive, in part, food seeking behavior following caloric restriction.

Bipolar disorders in severe anorexia nervosa: prevalence and relationships

BACKGROUND

The comorbidity between anorexia nervosa (AN) and bipolar disorders (BD) among subjects with AN is a matter of some debate, regarding its existence, its impact on the clinical manifestations of AN and the nature of the relationship between these disorders. Our aims were: (1) to evaluate the prevalence of BD among patients with severe AN; and (2) to determine whether people with a history of BD present particular clinical AN characteristics in comparison to people with a comorbid major depressive disorder or with any mood disorder comorbidity.

METHODS

177 AN subjects were surveyed to assess their nutritional state, dietary symptomatology, psychiatric comorbidities, treatments received and associated response. The diagnosis of BD relied on DSM-5 criteria, using the short-CIDI. The discriminant features of patients with AN and suspected BD were identified, comparing them to the characteristics of AN patients without any mood disorder and AN patients suffering from major depressive disorder.

RESULTS

Among AN subjects, 11.3% were suspected to have BD. In comparison with the two other groups, these patients had more severe clinical profiles in terms of duration of AN (6.7 years, p = 0.020), nutritional state (p max  =  0.031), levels of anxious, depressive and dietary symptoms, lifetime comorbidity with anxious disorders, quality-of-life (p =  0.001) and treatment (antidepressant and mood stabilizers, (p  =  0.029)).

LIMITATIONS

The participants were hospitalized in a tertiary center with severe AN. The diagnosis of BD requires evaluation using a more precise diagnostic instrument CONCLUSION: These results underline the importance of systematic early detection of BD and mood disorders among individuals with severe AN, to provide optimum treatment.

LEVEL OF EVIDENCE

III: Evidence obtained from a cross-sectional study.

The potential role of stimulants in treating eating disorders

BACKGROUND

Many individuals with eating disorders remain symptomatic after a course of psychotherapy and pharmacotherapy; therefore, the development of innovative treatments is essential.

METHOD

To learn more about the current evidence for treating eating disorders with stimulants, we searched for original articles and reviews published up to April 29, 2021 in PubMed and MEDLINE using the following search terms: eating disorders, anorexia, bulimia, binge eating, stimulants, amphetamine, lisdexamfetamine, methylphenidate, and phentermine.

RESULTS

We propose that stimulant medications represent a novel avenue for future research based on the following: (a) the relationship between eating disorders and attention deficit/hyperactivity disorder (ADHD); (b) a neurobiological rationale; and (c) the current (but limited) evidence for stimulants as treatments for some eating disorders. Despite the possible benefits of such medications, there are also risks to consider such as medication misuse, adverse cardiovascular events, and reduction of appetite and pathological weight loss. With those risks in mind, we propose several directions for future research including: (a) randomized controlled trials to study stimulant treatment in those with bulimia nervosa (with guidance on strategies to mitigate risk); (b) examining stimulant treatment in conjunction with psychotherapy; (c) investigating the impact of stimulants on "loss of control" eating in youth with ADHD; and (d) exploring relevant neurobiological mechanisms. We also propose specific directions for exploring mediators and moderators in future clinical trials.

DISCUSSION

Although this line of investigation may be viewed as controversial by some in the field, we believe that the topic warrants careful consideration for future research.

Baseline cortisol predicts drunkorexia in female but not male college students

"Drunkorexia" or compensatory eating behaviors in response to alcohol consumption, resembles a subclinical eating disorder, and is a current public health concern. Eating disorders and alcohol abuse are associated with dysfunction of the hypothalamic-pituitary-adrenal axis (HPA). One index of HPA function is cortisol. As causes of drunkorexia remain elusive, the present study examined cortisol function as it relates to drunkorexia. Participants:n = 73 (49 women) college students. Method: Participants provided daytime saliva samples for cortisol analyses prior to completing an online survey measuring alcohol consumption, drunkorexia, and alcohol problems as measured by the Rutgers Alcohol Problem Index (RAPI). Results: Multiple regressions indicated that baseline cortisol significantly positively correlated with drunkorexia behaviors in women but not men. Higher baseline cortisol and aspects of drunkorexia related to alcohol problems. Conclusion: Programs educating about stress management and health risks of drunkorexia may decrease engagement in drunkorexia behaviors among college students.

A feasibility study evaluating lisdexamfetamine dimesylate for the treatment of adults with bulimia nervosa

OBJECTIVE

This study examined the feasibility, safety, and potential efficacy of lisdexamfetamine (LDX) as a treatment for adults with bulimia nervosa (BN).

METHOD

An open-label 8-week feasibility study was conducted in participants with BN. Enrollment rate, dropout rate, safety outcomes, and eating disorder symptom change were examined.

RESULTS

Eighteen of 23 participants completed the study per protocol. There was no participant-initiated dropout due to adverse drug reactions and no severe and unexpected adverse drug reactions. An average increase in heart rate of 12.1 beats/min was observed. There was a mean weight reduction of 2.1 kg and one participant was withdrawn for clinically significant weight loss. In the intent-to-treat sample, there were reductions in objective binge episodes and compensatory behaviors from Baseline to Post/End-of-Treatment (mean difference = -29.83, 95% confidence interval: -43.38 to -16.27; and mean difference = -33.78, 95% confidence interval: -48.74 to -18.82, respectively).

DISCUSSION

Results of this study indicate that a randomized controlled trial would be feasible with close monitoring of certain safety parameters (especially over a longer time period as long-term safety is unknown). However, the results should not be used as evidence for clinicians to prescribe LDX to individuals with BN before its efficacy and safety are properly tested.

TRIAL REGISTRATION NUMBER

NCT03397446.

Multidimensional elements of impulsivity as shared and unique risk factors for food addiction and alcohol misuse

Food addiction (FA) and alcohol misuse tend to co-occur, which suggests shared factors in the etiology and persistence of these health behaviors. One shared factor that has been linked to both is impulsivity, a multidimensional construct reflecting multiple facets of self-regulatory capacity. However, co-occurrence also raises issues of possible confounding if both domains are not considered concurrently, and the intersection between FA, alcohol misuse, and impulsivity has not been well characterized empirically. Therefore, the current study examined the intersection of FA, alcohol consequences, and multiple indicators of impulsivity. Participants were emerging adults reporting regular heavy episodic drinking recruited from Hamilton, Ontario (N = 730; ages 19.5-23). Participants completed measures of FA, alcohol problems, impulsive personality traits (i.e., Barratt Impulsiveness Scales, UPPS-P Impulsive Behavior Scales), impulsive choice (i.e., delay discounting), impulsive action (i.e., Go/NoGo task). Findings revealed a significant association between FA and alcohol-related consequences and both shared similar associations with specific impulsive personality traits (Positive and Negative Urgency, Lack of Premeditation, Motor and Attentional Impulsivity). However, alcohol-related consequences were uniquely associated with other impulsive personality traits (Lack of Perseverance, Sensation Seeking, Non-planning impulsivity) and impulsive choice, and FA was uniquely associated with impulsive action. Beyond alcohol-related consequences, FA was associated with additional variance in measures of impulsive personality traits (Positive and Negative Urgency, Lack of Premeditation, Motor Impulsivity, and Attentional Impulsivity) and impulsive action, but not impulsive choice. Overall, the current study reveals several common self-regulatory processes associated with both adverse drinking consequences and FA, and that the risk of inadvertent confounding appears to be limited.

Binge-like palatable food intake in rats reduces preproglucagon in the nucleus tractus solitarius

Binge eating involves eating larger than normal quantities of food within a discrete period of time. The neurohormonal controls governing binge-like palatable food intake are not well understood. Glucagon-like peptide-1 (GLP-1), a hormone produced peripherally in the intestine and centrally in the nucleus tractus solitarius (NTS), reduces food intake. Given that the NTS plays a critical role in integrating peripheral and central signals relevant for food intake, as well as the role of GLP-1 in motivated feeding, we tested the hypothesis that expression of the GLP-1 precursor preproglucagon (PPG) would be reduced in the NTS of rats with a history of binge-like palatable food intake. Adult male rats received access to fat for 1 h shortly before lights off, either every day (Daily, D) or only 3d/week (Intermittent, INT). INT rats ate significantly more fat than did D rats in sessions where all rats had fat access. After ~8.5 weeks of diet maintenance, we measured plasma GLP-1 as well as NTS PPG and GLP-1 receptor expression. INT rats had significantly lower NTS PPG mRNA expression compared to D rats. However, plasma GLP-1 was significantly increased in the INT group versus D rats. No significant differences were observed in NTS GLP-1 receptor expression. We also measured plasma insulin levels, fasted blood glucose, and plasma corticosterone but no differences were detected between groups. These results support the hypothesis that binge-like eating reduces NTS GLP-1 expression, and furthermore, demonstrate divergent impacts of binge-like eating on peripheral (plasma) versus central GLP-1.

Expectancies about the Effects of Cannabis Use on Eating Disorder Symptoms

Background: Substance use, specifically cannabis use, is common among individuals with eating disorder (ED) symptoms; however, few studies have specifically explored the relation between EDs and cannabis use. Purpose: The present study examined expectancies about the impact of cannabis on cognitive, affective and behavioral ED symptoms. Additionally, this study explored associations between cannabis-related expectancies, cannabis use and cannabis-related problems. Methods: Cannabis users with ED symptoms (N = 137) reported on frequency of cannabis use, cannabis-related problems and expectancies about the impact of cannabis on ED symptoms, Results: Participants expected cannabis to decrease restrictive eating, compensatory behaviors, and preoccupation with body shape and weight and fear of eating and weight gain. In contrast, cannabis was expected to increase binge-eating behaviors. Expectancies about the impact of cannabis use on ED symptoms were not associated with more frequent cannabis use nor were they associated with cannabis-related problems. Conclusions: These findings suggest that individuals believe cannabis will improve some ED symptoms; however, these expected improvements are not associated with increased cannabis use and problems. Future research should examine cannabis expectancies in clinical populations and should further explore the association between cannabis expectancies, use, and ED symptoms longitudinally.

Comorbid drug use disorders and eating disorders — a review of prevalence studies

Aims

This study reviews literature on comorbidity of drug use disorders (DUD) and eating disorders (ED). The article updates knowledge on the occurrence of comorbidity of these diagnoses.

Methods

The databases Embase, Medline and PsycInfo were searched for studies published between 1990 and May 2011, with combinations of the terms ‘eating disorder’, ‘substance-related disorder’, ‘drug dependence’, ‘drug abuse’, ‘drug addiction’ and ‘substance abuse’. This generated altogether 596 studies. Studies in which diagnostic DUD and ED were not assessed in the same sample or the result was not given in percentages were excluded. Thirteen studies remained.

Results

In 11 of the 13 studies, the participants were initially diagnosed with an eating disorder. The prevalence of lifetime drug use disorders varies from 8–43 %. In two studies, DUD is the initial diagnosis, and the participants report 14 % concurrent and 27.3% lifetime ED. The most prevalent co-occurring diagnoses tend to be bulimia nervosa/bingeing-purging anorexia nervosa, and stimulants/cannabis disorders.

Conclusions

The lifetime prevalence percentages of eating disorders in people with drug use disorders (and vice versa) are higher than in the general population. The results indicate that the field of drug disorder treatment and research could benefit from paying closer attention to the risk of eating disorders.

In-transition culture of experimentation with cannabis in Latin American college students: A new role within a potential drug use sequencing pattern

INTRODUCTION AND AIMS

Given a scenario of intense discussion about the legal situation of cannabis users worldwide, this paper aims to investigate the role of cannabis within a drug use sequencing pattern.

DESIGN AND METHODS

Data came from a representative sample of college students from 27 Brazilian capitals (n = 12 711). We analysed the patterns of transition from/to the first use of cannabis to/from the first use of alcohol, tobacco and seven other illegal drugs. Survival analysis methods were used to analyse age of onset data on all potential drug pairs. Drugs that were not specified as the target drug pair tested in each survival model were included as time-varying covariates in all models.

RESULTS

We found significant transitions from alcohol [adjusted hazard ratio (aHR) = 1.41, 95% confidence interval (CI) 1.15-1.73, P < 0.001] and inhalants (aHR = 1.56, 95% CI 1.26-1.93, P < 0.001) to cannabis. Moreover, we found significant transitions from cannabis to alcohol (aHR = 2.40, 95% CI 1.47-3.91, P < 0.001), cocaine (aHR = 7.47, 95% CI = 4.26-13.09, P < 0.001), prescription opioids (aHR = 2.16, 95% CI 1.29-3.63, P < 0.01) and tranquilisers (aHR = 1.51, 95% CI 1.11-2.06, P < 0.01).

DISCUSSION AND CONCLUSIONS

Overall, our findings point to a strategic role of cannabis within drug first use sequence pattern. We had an important and unexpected finding-the bi-directional relationship between alcohol and cannabis. In addition, the first use of cannabis still precedes the first use of cocaine and non-medical use of tranquilisers and prescription opioids. [Castaldelli-Maia JM, Nicastri S, Cerdá M, Kim JH, Oliveira LG, Andrade AG, Martins, SS. In-transition culture of experimentation with cannabis in Latin American college students: A new role within a potential drug use sequencing pattern. Drug Alcohol Rev 2017;00:000-000].

Psychiatric co-morbidity in women presenting across the continuum of disordered eating

OBJECTIVE

To compare the prevalence and correlates of psychiatric co-morbidity across a large sample of college women without an eating disorder, those at high risk for an eating disorder and women diagnosed using DSM-5 criteria for an eating disorder.

PARTICIPANTS

549 college women aged 18-25.

METHODS

Data from the Eating Disorder Examination, the Structured Clinical Interview for DSM-IV Axis I disorders and self-report questionnaires were analyzed using logistic regression for categorical data and ANCOVA for continuous measures.

RESULTS

Eating disordered symptomatology was strongly associated with anxiety disorders, mood disorders and insomnia. These co-morbidities (type and severity) tend to increase with eating disorder symptom severity.

CONCLUSIONS

Prevention and treatment programs for eating disorders need to address the high levels of mood, anxiety and sleep problems in this population. The findings on insomnia are novel and suggest that sleep disturbance may play an integral role in eating-related difficulties.

Use transition between illegal drugs among Brazilian university students

PURPOSE

The aim of the present study was to test whether the first use of an illicit drug increases the chance of first use of other illicit drugs.

METHOD

The transitions from the first use of a drug to the first use of another drug were analyzed. Comparisons were made between first drug users and non-users. Survival analysis methods were used to compare the cumulative probability of second drug use after adjusting for socio-demographic covariates and the intermediate use of alcohol and/or tobacco. A total of 12,721 Brazilian university students participated in this study.

RESULTS

Inhalants and marijuana were used prior to the use of several other drugs, whereas the opposite pattern was not found. Ecstasy was used before other drugs in several instances. Other well-examined drugs, such as amphetamines, cocaine and hallucinogens, were used both before and after other illicit drugs without any marked predominance for either of the two roles.

CONCLUSIONS

This study supports the role of the use of marijuana and inhalants almost exclusively before the use of other illicit drugs, whereas the use of ecstasy has an opposite role. These roles could be linked to the prevalence of lifetime use and whether individuals were at an earlier or later age during experimentation.

The relationship between Internet addiction and bulimia in a sample of Chinese college students: depression as partial mediator between Internet addiction and bulimia

BACKGROUND

It has been reported that Internet addiction is associated with substance dependence. Eating disorders have high rates of co-morbidity with substance use disorders. The relationship between Internet addiction and eating disorders was reported in a previous study.

AIMS

To examine the hypothesis that Internet addiction is closely associated with bulimia. The hypothesis that depression mediates the relationship between Internet addiction and bulimia symptoms was also tested.

METHODS

2,036 Chinese college students were assessed on Internet addiction, eating behaviors and depression. Binge eating, compensatory behaviors, weight concern, menarche and weight change were also reported. Multiple regression analysis was used to test the mediating effect of depression.

RESULTS

Internet addicts showed significantly higher scores on most subscales on EDI-1 than the controls. They reported significantly more binge eating, weight concern and weight change than the controls. Among all of the participants, depression was found to be a partial mediator in the relationship between Internet addiction and bulimia.

CONCLUSION

This survey provides evidence of the co-morbidity of Internet addiction and bulimia.

Assessment of anorexia nervosa: an overview of universal issues and contextual challenges

AIM

Anorexia Nervosa (AN) is a complex and clinically challenging syndrome. Intended for specialist audiences, this narrative review aims to summarise the available literature related to assessment in the adult patient context, synthesising both research evidence and clinical consensus guidelines.

METHOD

We provide a review of the available literature on specialist assessment of AN focusing on common trajectories into assessment, obstacles accessing assessment, common presenting issues and barriers to the assessment process, the necessary scope of assessment, and tools and techniques. It describes the further step of synthesising assessment information in ways that can inform resultant care plans.

RESULTS

In addition to assessment of core behaviours and diagnostic skills, considerations for the expert assessor include the functions of primary care, systemic and personal barriers, knowledge of current assessment tools and research pertaining to comorbid pathology in AN, assessing severity of illness, role of family at assessment, as well as medical, nutritional and compulsory elements of assessment.

CONCLUSION

Comprehensive assessment of AN in the current healthcare context still remains largely the remit of the specialist ED clinician. Assessment should remain an on-going process, paying particular attention to available empirical evidence, thereby reducing the gap between research and practice.

Does anorexia nervosa resemble an addiction?

Anorexia nervosa is a severe psychiatric disorder characterized by unrelenting self-starvation and life-threatening weight loss. The relentlessness with which individuals with anorexia nervosa pursue starvation and in some cases exercise despite the negative physical, emotional, and social consequences parallels features of addictive disorders. From a clinical perspective, individuals with anorexia nervosa behave similarly to individuals with substance abuse by narrowing their behavioral repertoire so that weight loss, restricting food intake, and excessive exercise interfere with other activities in much the same way that substance abuse does. However, fundamental differences exist between anorexia nervosa and substance abuse that suggest anorexia nervosa is not an addiction in and of itself.

A Heuristic for Developing Transdiagnostic Models of Psychopathology

Transdiagnostic models of psychopathology are increasingly prominent because they focus on fundamental processes underlying multiple disorders, help to explain comorbidity among disorders, and may lead to more effective assessment and treatment of disorders. Current transdiagnostic models, however, have difficulty simultaneously explaining the mechanisms by which a transdiagnostic risk factor leads to multiple disorders (i.e., multifinality) and why one individual with a particular transdiagnostic risk factor develops one set of symptoms while another with the same transdiagnostic risk factor develops another set of symptoms (i.e., divergent trajectories). In this article, we propose a heuristic for developing transdiagnostic models that can guide theorists in explicating how a transdiagnostic risk factor results in both multifinality and divergent trajectories. We also (a) describe different levels of transdiagnostic factors and their relative theoretical and clinical usefulness, (b) suggest the types of mechanisms by which factors at 1 level may be related to factors at other levels, and (c) suggest the types of moderating factors that may determine whether a transdiagnostic factor leads to certain specific disorders or symptoms and not others. We illustrate this heuristic using research on rumination, a process for which there is evidence it is a transdiagnostic risk factor.

Bulimia nervosa among methamphetamine dependent adults: association with outcomes three years after treatment

Although weight loss is among the most commonly cited reasons for using methamphetamine (MA), little is known about the association between eating disorders and treatment outcomes in this population. This study examined psychiatric, substance use, and functional outcomes of MA users (N = 526) with bulimia nervosa 3 years after treatment for MA dependence. Bulimia nervosa was observed among 2.4% (N = 13) of the participants and was associated with poorer MA use outcomes, increased health service utilization, and higher levels of functional impairment. Addressing MA use among adults with eating disorders may be helpful as a means of improving treatment outcomes.

Neurobiology of aversive states

Hoebel and colleagues are often known as students of reward and how it is coded in the CNS. This article, however, attempts to focus on the significant advances by Hoebel and others in dissecting out behavioral components of distinct aversive states and in understanding the neurobiology of aversion and the link between aversive states and addictive behaviors. Reward and aversion are not necessarily dichotomous and may reflect an affective continuum contingent upon environmental conditions. Descriptive and mechanistic studies pioneered by Bart Hoebel have demonstrated that the shift in the reward-aversion spectrum may be, in part, a result of changes in central dopamine/acetylcholine ratio, particularly in the nucleus accumbens. The path to aversion appears to include a specific neurochemical signature: reduced dopamine release and increased acetylcholine release in "reward centers" of the brain. Opioid receptors may have a neuromodulatory role on both of these neurotransmitters.

Patterns of associations between eating disordered behaviors and substance use in two non-clinical samples: a university and a community based sample

This study examined shared patterns of associations between disordered eating behaviors and substance use in two different non-clinical samples of young women. Participants were recruited from a university (526 women) and varied community (517 women) settings. Participants completed the Women's Health Survey, examining engagement in a wide range of licit and illicit substances and disordered eating patterns during the past 12 months. In both samples, the cluster of bingeing, dieting and purging was significantly associated with binge drinking, drinking associated with negative consequences, and with cocaine use. The cluster of dieting and purging was associated with the use of stimulants/amphetamines. Health services, including assessment and treatment, and health promotion activities, should consider these patterns of comorbidity.

Insulin signaling and addiction

Across species, the brain evolved to respond to natural rewards such as food and sex. These physiological responses are important for survival, reproduction and evolutionary processes. It is no surprise, therefore, that many of the neural circuits and signaling pathways supporting reward processes are conserved from Caenorhabditis elegans to Drosophilae, to rats, monkeys and humans. The central role of dopamine (DA) in encoding reward and in attaching salience to external environmental cues is well recognized. Less widely recognized is the role of reporters of the "internal environment", particularly insulin, in the modulation of reward. Insulin has traditionally been considered an important signaling molecule in regulating energy homeostasis and feeding behavior rather than a major component of neural reward circuits. However, research over recent decades has revealed that DA and insulin systems do not operate in isolation from each other, but instead, work together to orchestrate both the motivation to engage in consummatory behavior and to calibrate the associated level of reward. Insulin signaling has been found to regulate DA neurotransmission and to affect the ability of drugs that target the DA system to exert their neurochemical and behavioral effects. Given that many abused drugs target the DA system, the elucidation of how dopaminergic, as well as other brain reward systems, are regulated by insulin will create opportunities to develop therapies for drug and potentially food addiction. Moreover, a more complete understanding of the relationship between DA neurotransmission and insulin may help to uncover etiological bases for "food addiction" and the growing epidemic of obesity. This review focuses on the role of insulin signaling in regulating DA homeostasis and DA signaling, and the potential impact of impaired insulin signaling in obesity and psychostimulant abuse.

Eating disorder symptomatology and substance use disorders: prevalence and shared risk in a population based twin sample

OBJECTIVE

Research shows a significant association between eating disorders (ED) and substance use disorders (SUD). The objective of this study is to examine the prevalence, chronology, and possibility of shared familial risk between SUD and ED symptomatology.

METHOD

Subjects included 1,206 monozygotic and 877 dizygotic adult female twins. ED symptomatology included anorexia (AN) and bulimia nervosa (BN) diagnosis, symptoms associated with diagnostic criteria, and BN symptom count. SUD included alcohol, illicit drug, and caffeine abuse/dependence. Generalized estimated equation modeling was used to examine phenotypic associations, and Choleksy decompositions were used to delineate the contribution of genes and environment to comorbidity.

RESULTS

There were no significant differences between SUD prevalence in women with AN and BN. Women with BN reported BN preceded SUD development while the reverse was true for AN. Twin analyses showed possible familial overlap between BN symptomatology and all SUD examined.

DISCUSSION

Results suggest an important difference in the chronology of EDs and SUDs. Women with BN may be turning to substances to dampen bulimic urges. Women with AN may be engaging in substance use initially in an effort to lose weight. Results also suggest familial factors contribute to the comorbidity between BN and SUD.

A nonsynonymous polymorphism in cannabinoid CB2 receptor gene is associated with eating disorders in humans and food intake is modified in mice by its ligands

Marijuana use activates cannabinoid receptors (CB-Rs) producing several behavioral effects related to addiction, mood, and appetite. We investigated the association between CNR2 gene, which encodes cannabinoid CB2 receptor (CB2-R) and eating disorders in 204 subjects with eating disorders and 1876 healthy volunteers in Japanese population. The effect of treatment with CB2-R ligands on mouse food consumption was also determined. The CB2-R ligands used suppressed food intake in a time- and strain-dependent manner when food was available ad libitum and during the 12-h fast except, AM 630-the CB2-R antagonist that stimulated food consumption in food-deprived mice. There is an association between the R63Q polymorphism of the CNR2 gene and eating disorders (P = 0.04; Odds ratio 1.24, 95% CI, (1.01-1.53). These results suggest that cannabinoid CB2-R is involved in the endocannabinoid signaling mechanisms associated with the regulation of food intake and in eating disorders.

Substance use disorders in women with anorexia nervosa

OBJECTIVE

We examined prevalence of substance use disorders (SUD) in women with: (1) anorexia nervosa (AN) restricting type (RAN); (2) AN with purging only (PAN); (3) AN with binge eating only (BAN); and (4) lifetime AN and bulimia nervosa (ANBN). Secondary analyses examined SUD related to lifetime purging behavior and lifetime binge eating.

METHOD

Participants (N = 731) were drawn from the International Price Foundation Genetic Studies.

RESULTS

The prevalence of SUD differed across AN subtypes, with more in the ANBN group reporting SUD than those in the RAN and PAN groups. Individuals who purged were more likely to report substance use than those who did not purge. Prevalence of SUD differed across lifetime binge eating status.

DISCUSSION

SUD are common in AN and are associated with bulimic symptomatology. Results underscore the heterogeneity in AN, highlighting the importance of screening for SUD across AN subtypes.

Patterns of co-morbidity of eating disorders and substance use in Swedish females

BACKGROUND

Little is known about the association of eating disorder subtypes across multiple categories of substance use in population-based samples. We examined the association between eating disorders and substance use in a large population-based sample.

METHOD

Female participants (n=13 297) were from the Swedish Twin Registry [Lichtenstein et al., Twin Research and Human Genetics (2006) 9, 875-882]. Substance use was examined in four defined groups - (1) anorexia nervosa (AN); (2) bulimia nervosa (BN); (3) AN and BN (ANBN); and (4) binge eating disorder (BED) as well as a referent group without eating disorder (no ED). Secondary analyses examined differences between restricting AN (RAN) and binge and/or purge AN (ANBP).

RESULTS

In general, eating disorders were associated with greater substance use relative to the referent. The AN group had significantly increased odds for all illicit drugs. Significant differences emerged across the RAN and ANBP groups for alcohol abuse/dependence, diet pills, stimulants, and polysubstance use with greater use in the ANBP group. Across eating disorder groups, (1) the BN and ANBN groups were more likely to report alcohol abuse/dependence relative to the AN group, (2) the ANBN group was more likely to report diet pill use relative to the AN, BN and BED groups, and (3) the BN group was more likely to report diet pill use relative to the no ED, AN and BED groups.

CONCLUSIONS

Eating disorders are associated with a range of substance use behaviors. Improved understanding of how they mutually influence risk could enhance understanding of etiology and prevention.

The relationship between concurrent substance use disorders and eating disorders with personality disorders

Objective:

The current pilot study investigated whether patients with concurrent substance use disorders and eating disorders (SUD and ED) who experienced a reduction in SUD and ED symptoms following treatment for SUD and ED also experienced a reduction in personality disorder (PD) symptoms.

Method:

Twenty patients with SUD and ED and PD were assessed pre and post treatment using clinical interviews, self-report questionnaires, and a therapist questionnaire on DSM-IV-TR symptoms for PD.

Results:

Symptoms for the personality disorders were reduced following treatment. This reduction was correlated with a decrease in the number of symptoms of ED at post treatment.

Discussion:

Chronic concurrent SUD and ED may make it difficult to separate PD symptoms from co-occurring disorders. Many features attributed to PDs may be reduced when problematic substance use and disordered eating are addressed, a fact that may increase clinician and patients’optimism about therapeutic change.

Are anorexia nervosa and bulimia nervosa separate disorders? Challenging the 'transdiagnostic' theory of eating disorders

BACKGROUND

Anorexia nervosa (AN) and bulimia nervosa (BN) are classified as separate and distinct clinical disorders. Recently, there has been support for a transdiagnostic theory of eating disorders, which would reclassify them as one disorder.

OBJECTIVE

To determine whether AN and BN are a single disorder with one cause or separate disorders with different causes.

METHOD

Hill's Criteria of Causation were used to test the hypothesis that AN and BN are one disorder with a single cause. Hill's Criteria of Causation demand that the minimal conditions are needed to establish a causal relationship between two items which include all of the following: strength of association, consistency, temporality, biological gradient, plausibility, coherence, experimental evidence and analogy.

RESULTS

The hypothesis that AN and BN have a single cause did not meet all of Hill's Criteria of Causation. Strength of association, plausibility, analogy and some experimental evidence were met, but not consistency, specificity, temporality, biological gradient, coherence and most experimental evidence.

CONCLUSIONS

The hypothesis that AN and BN are a single disorder with a common cause is not supported by Hill's Criteria of Causation. This argues against the notion of a transdiagnostic theory of eating disorders.

A cross-lagged evaluation of eating disorder symptomatology and substance-use problems

OBJECTIVE

The purpose of this study was to conduct a temporal examination of the associations among disordered eating behaviors, substance use, and use-related negative consequences in female college students-a population at high risk for developing eating and substance-use disorders.

METHOD

Participants completed assessments of disordered eating behaviors, alcohol and drug use, and use-related negative consequences.

RESULTS

Results support previous research suggesting that disordered eating behaviors are more strongly associated with alcohol- and substance-related problems rather than use per se. With respect to temporal precedence, results indicated that binge eating preceded alcohol-use problems, but a bidirectional relationship was found for vomiting. With regard to drug problems, laxatives use preceded drug problems, whereas drug problems preceded fasting. These associations were not better accounted for by pre-existing eating or substance-use problems or psychiatric distress (e.g., depression, anxiety).

CONCLUSIONS

This study further supports the importance of assessing consequences, in addition to use patterns, when examining substance use in individuals demonstrating threshold and subthreshold eating-disordered behaviors.

Disordered eating and weight changes after deployment: longitudinal assessment of a large US military cohort

The effect of military deployments to combat environments on disordered eating and weight changes is unknown. Using longitudinal data from Millennium Cohort Study participants who completed baseline (2001-2003) and follow-up (2004-2006) questionnaires (n=48,378), the authors investigated new-onset disordered eating and weight changes in a large military cohort. Multivariable logistic regression was used to compare these outcomes among those who deployed and reported combat exposures, those who deployed but did not report combat exposures, and those who did not deploy in support of the wars in Iraq and Afghanistan. Deployment was not significantly associated with new-onset disordered eating in women or men, after adjustment for baseline demographic, military, and behavioral characteristics. However, in subgroup comparison analyses of deployers, deployed women reporting combat exposures were 1.78 times more likely to report new-onset disordered eating (95% confidence interval: 1.02, 3.11) and 2.35 times more likely to lose 10% or more of their body weight compared with women who deployed but did not report combat exposures (95% confidence interval: 1.17, 4.70). Despite no significant overall association between deployment and disordered eating and weight changes, deployed women reporting combat exposures represent a subgroup at higher risk for developing eating problems and weight loss.

Lifetime substance abuse, family history of alcohol abuse/dependence and novelty seeking in eating disorders: comparison study of eating disorder subgroups

AIM

To assess lifetime substance abuse, family history of alcohol abuse/dependence, and novelty seeking in three different eating disorder groups (anorexia nervosa-restrictive; anorexia nervosa-binge eating/purging; anorexia nervosa to bulimia nervosa).

METHOD

A total sample of 371 eating disorder patients participated in the current study. Assessment measures included the prevalence of substance abuse and family history of alcohol abuse/dependence as well as the novelty-seeking subscale of the Temperament and Character Inventory-Revised.

RESULTS

Significant differences across groups were detected for lifetime substance abuse, with anorexia nervosa-restrictive individuals exhibiting a significant lower prevalence than the anorexia nervosa to bulimia nervosa and anorexia nervosa-binge eating/ purging patients (P < 0.01). For family history of alcohol abuse/dependence the same pattern was observed (P = 0.04). Novelty seeking was associated with substance abuse (P = 0.002), with the anorexia nervosa to bulimia nervosa group exhibiting significantly higher scores on the novelty-seeking scale than the other two groups (P < 0.001). But family history of alcohol abuse/dependence was not related to novelty seeking (P = 0.092).

CONCLUSION

Lifetime substance abuse appears to be more prevalent in anorexia nervosa patients with bulimic features. Higher novelty-seeking scores may be associated with diagnosis cross-over.

Rhabdomyolysis and drug abuse in a patient with bulimia nervosa

OBJECTIVE

Eating disorders, particularly bulimia nervosa, have long been associated with alcohol and illicit drug abuse. Impulsivity has been linked to substance abuse, but there are other explanations for this association. This comorbidity could be very harmful, even deadly, because of the medical consequences of drug abuse.

METHOD

This article reports on the case of a 23-year-old woman with bulimia nervosa, severe alcohol and illicit drug abuse, and impulsive behavior who developed rhabdomyolysis. One of the reasons for her drug addiction was the effect of these substances in appetite suppression.

RESULTS

The patient successfully recovered after medical and psychological treatment.

CONCLUSION

This article presents the case of a patient with bulimia nervosa and a serious medical complication of illicit drug abuse. It is important to be aware of the increased risk of morbidity and mortality for this patient group.

Relationship between body image and stimulant use among Canadian adolescents

This study investigated the relationship between body image, dieting, disordered eating behaviors, and stimulant use in a sample of more than 30,000 British Columbian students. For both males and females, significant associations were found between stimulant use and body satisfaction, binging and purging, and efforts to lose weight.

Disordered eating and substance use in high-school students: results from the Youth Risk Behavior Surveillance System

OBJECTIVE

To examine the association between disordered eating (fasting, diet product use, and vomiting or laxative use) and use of 10 substances (cigarettes, alcohol, marijuana, cocaine, inhalants, heroin, methamphetamines, ecstasy, steroids, and hallucinogens) in a nationally representative adolescent sample.

METHOD

Participants were 13,917 U.S. high-school students participating in the 2005 Youth Risk Behavior Surveillance System.

RESULTS

Disordered eating was significantly associated with the use of each substance. Using effect size estimates that take base rates into consideration, for female students, associations between substance use and disordered eating were weak for all but three forms of substance use: current smoking, binge drinking, and inhalants. Among male students, strong (marijuana, steroids, and inhalants) or moderate effects (all other substances) were observed.

CONCLUSION

Future research needs to focus on inhalant use and methamphetamine use in males. Increased medical attention should be directed toward adolescents who practice disordered eating behaviors because they are also at elevated risk for using cigarettes, alcohol, inhalants, methamphetamines, and steroids.

Interactions between eating disorders and drug abuse

To examine the relationship between drug abuse and eating disorders in a longitudinal sample. In a prospective study, women diagnosed with either DSM-IV anorexia nervosa (n = 136) or bulimia nervosa (n = 110) were interviewed and assessed for research diagnostic criteria drug use disorder (DUD) every 6-12 months over 8.6 years. Contrary to expectation, DUD did not influence recovery from either eating disorder. Multivariate analyses indicated that alcohol use and suicide attempts over the course of the study, as well as hospitalization for an affective disorder before the study, predicted DUD in anorexia nervosa. For bulimia nervosa, multivariate predictors included the severity of alcohol use and the severity of bulimic symptoms over the course of the study, and a hospitalization before study entry for a nonaffective disorder. Drug abuse in women with eating disorders is an area of clinical concern and should be monitored routinely.

Treatment dropout in drug-addicted women: are eating disorders implicated?

A high prevalence of eating disorders among drug-addicted female patients has been noted, and it could be associated to psychopathological underlying factors. Our aim was to assess eating disorder traits in women approaching a residential program for drug addiction. We hypothesized that these traits would correlate to more general psychopathological factors, and would influence treatment relapse. A sample of 204 substance dependent women attending a residential treatment was screened for psychopathological indices, and follow-up data were obtained at the end of the treatment. Clients had a high risk for eating disorders (15%), and lifetime prevalence was even higher (20%). Disordered eating was associated to psychopathological distress, in particular harm avoidance resulted significantly lower (p=0.005), evoking higher unresponsiveness to danger. Drug addiction treatment outcome is associated to completion of defined programs, and eating disorder was a key covariable in determining treatment relapse or success (p=0.03). Clinicians should be aware of this potential co-morbidity, and concurrent treatments should be attempted, in order to prevent symptomatic shifting.

Personality pathology and substance abuse in eating disorders: a longitudinal study

OBJECTIVE

Substance abuse has been shown to predict poor outcome in eating disorder (ED) samples, and prior cross-sectional data on personality subtypes of EDs suggest that substance abuse is associated with dysregulated and possibly avoidant-insecure subtypes. This study investigates longitudinal associations between personality and substance use.

METHOD

Personality pathology and substance use were assessed in 213 individuals with anorexia nervosa and bulimia nervosa at baseline; substance use was assessed at regular follow-up intervals over a 9-year period.

RESULTS

Of the five personality factors identified, the obsessional-sensitive and high-functioning types were negatively associated with substance abuse at baseline, while the behaviorally dysregulated type was positively associated with substance abuse at baseline. Longitudinal associations were observed, suggesting that obsessional-sensitive personality type was protective against the development of substance abuse. Longitudinal associations between the other personality types and substance abuse were nonsignificant after baseline substance abuse history was included as a covariate in the model.

CONCLUSION

Substance use demonstrates cross-sectional associations with personality style, but substance abuse history appears to be the most important predictor of future substance abuse in women with eating disorders.

Prognosis of adolescent partial syndromes of eating disorder

BACKGROUND

Partial syndromes of eating disorder are common in adolescents but the health significance of these syndromes remains uncertain.

AIMS

To document the health and social adjustment in young adulthood of females assessed as having a partial syndrome of eating disorder in adolescence.

METHOD

A community sample of 1943 participants was tracked over 10 years in an eight-wave cohort study. A partial syndrome was defined as the fulfilment of at least two DSM-IV criteria for either anorexia or bulimia nervosa at one assessment or more between the ages of 15 years and 17 years.

RESULTS

Partial syndromes were found in 9.4% of 15- to 17-year-old female participants and 1.4% of males. There were few instances of progression of partial syndromes to fully fledged anorexia and bulimia nervosa. However, among those with partial syndromes depressive and anxiety symptoms were two to three times higher in young adulthood, substance misuse was common, and a majority of those with a partial syndrome of anorexia nervosa were still underweight in their mid-20s.

CONCLUSIONS

Given the level of subsequent psychopathology and social role impairment, there may be justification for initiating trials of preventive and early clinical intervention strategies for adolescent partial syndromes.

Baclofen for binge eating: an open-label trial

OBJECTIVE

Baclofen is a GABA-B agonist that may be useful in the treatment of substance use disorders, and also reduces 'binge-like' eating in rodents. We hypothesized that baclofen might be effective in reducing binge eating episodes in binge eating disorder (BED) and bulimia nervosa (BN).

METHOD

Seven women with BED (n = 4) or BN (n = 3) took baclofen (60 mg/day) for 10 weeks.

RESULTS

Six out of seven patients completed the full 10-week trial. Five out of seven participants (3 BED; 2 BN) demonstrated 50% or greater reduction of frequency of binge eating from beginning to end of the study. Three out of seven participants (2 BED; 1 BN) were free of binge eating at study end. Four out of seven participants elected to continue baclofen at study end. Baclofen was well tolerated by the participants.

CONCLUSION

In this open-label trial, baclofen was associated with decreased binge eating frequency in patients with BED and BN.

Eating disorders and suicide ideation: the mediating role of depression and aggressiveness

OBJECTIVE

Symptoms of depression and aggressiveness are important antecedents and correlates of suicide ideation and completion in adolescents and adults. Among adolescents, eating disorder symptoms were also found to associate with suicidal behavior. This study was aimed at investigating the role of depression and aggressiveness as mediators in the links between eating disorder symptoms and suicide ideation among adolescents, taking into account age and sex as covariates.

METHOD

Data from the Conegliano Eating Disorders Survey were used to investigate the role of depression and aggressiveness in the links between eating disorder symptoms and suicide ideation, resorting to a bootstrapped sampling distribution model.

RESULTS

In a mixed male-female sample of 930 adolescents, eating disorder symptoms were positively related to suicide ideation, taking age and sex into account. Depression and aggressiveness acted as full mediators in the links between eating disorder symptoms and suicidality, and virtually abolished any direct influence of eating disorders on suicide ideation.

CONCLUSION

Because of the cross-sectional nature of this study and the resorting to self-report scales, no firm statement about causal association can be made. However, both suicidal behavior and eating disorder symptoms are a rather widespread occurrence among adolescents, hence the investigation on suicidal tendencies in young people might benefit from the inclusion of measures of eating disorders to prevent the worst outcomes of minor psychological distress.