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Recent advances in understanding anorexia nervosa.
Anorexia nervosa is a complex psychiatric illness associated with food restriction and high mortality. Recent brain research in adolescents and adults with anorexia nervosa has used larger sample sizes compared with earlier studies and tasks that test specific brain circuits. Those studies have produced more robust results and advanced our knowledge of underlying biological mechanisms that may contribute to the development and maintenance of anorexia nervosa. It is now recognized that malnutrition and dehydration lead to dynamic changes in brain structure across the brain, which normalize with weight restoration. Some structural alterations could be trait factors but require replication. Functional brain imaging and behavioral studies have implicated learning-related brain circuits that may contribute to food restriction in anorexia nervosa. Most notably, those circuits involve striatal, insular, and frontal cortical regions that drive learning from reward and punishment, as well as habit learning. Disturbances in those circuits may lead to a vicious cycle that hampers recovery. Other studies have started to explore the neurobiology of interoception or social interaction and whether the connectivity between brain regions is altered in anorexia nervosa. All together, these studies build upon earlier research that indicated neurotransmitter abnormalities in anorexia nervosa and help us develop models of a distinct neurobiology that underlies anorexia nervosa
Could dopamine agonists aid in drug development for anorexia nervosa?
Anorexia nervosa is a severe psychiatric disorder most commonly starting during the teenage-years and associated with food refusal and low body weight. Typically there is a loss of menses, intense fear of gaining weight, and an often delusional quality of altered body perception. Anorexia nervosa is also associated with a pattern of high cognitive rigidity, which may contribute to treatment resistance and relapse. The complex interplay of state and trait biological, psychological, and social factors has complicated identifying neurobiological mechanisms that contribute to the illness. The dopamine D1 and D2 neurotransmitter receptors are involved in motivational aspects of food approach, fear extinction, and cognitive flexibility. They could therefore be important targets to improve core and associated behaviors in anorexia nervosa. Treatment with dopamine antagonists has shown little benefit, and it is possible that antagonists over time increase an already hypersensitive dopamine pathway activity in anorexia nervosa. On the contrary, application of dopamine receptor agonists could reduce circuit responsiveness, facilitate fear extinction, and improve cognitive flexibility in anorexia nervosa, as they may be particularly effective during underweight and low gonadal hormone states. This article provides evidence that the dopamine receptor system could be a key factor in the pathophysiology of anorexia nervosa and dopamine agonists could be helpful in reducing core symptoms of the disorder. This review is a theoretical approach that primarily focuses on dopamine receptor function as this system has been mechanistically better described than other neurotransmitters that are altered in anorexia nervosa. However, those proposed dopamine mechanisms in anorexia nervosa also warrant further study with respect to their interaction with other neurotransmitter systems, such as serotonin pathways
Altered structural and effective connectivity in anorexia and bulimia nervosa in circuits that regulate energy and reward homeostasis.
Anorexia and bulimia nervosa are severe eating disorders that share many behaviors. Structural and functional brain circuits could provide biological links that those disorders have in common. We recruited 77 young adult women, 26 healthy controls, 26 women with anorexia and 25 women with bulimia nervosa. Probabilistic tractography was used to map white matter connectivity strength across taste and food intake regulating brain circuits. An independent multisample greedy equivalence search algorithm tested effective connectivity between those regions during sucrose tasting. Anorexia and bulimia nervosa had greater structural connectivity in pathways between insula, orbitofrontal cortex and ventral striatum, but lower connectivity from orbitofrontal cortex and amygdala to the hypothalamus (P<0.05, corrected for comorbidity, medication and multiple comparisons). Functionally, in controls the hypothalamus drove ventral striatal activity, but in anorexia and bulimia nervosa effective connectivity was directed from anterior cingulate via ventral striatum to the hypothalamus. Across all groups, sweetness perception was predicted by connectivity strength in pathways connecting to the middle orbitofrontal cortex. This study provides evidence that white matter structural as well as effective connectivity within the energy-homeostasis and food reward-regulating circuitry is fundamentally different in anorexia and bulimia nervosa compared with that in controls. In eating disorders, anterior cingulate cognitive-emotional top down control could affect food reward and eating drive, override hypothalamic inputs to the ventral striatum and enable prolonged food restriction
A systematic review of studies probing longitudinal associations between anxiety and anorexia nervosa
The current study aimed to establish whether anxiety predicts subsequent anorexia nervosa onset and maintenance. A systematic review of longitudinal studies assessing the association between stable anxiety exposures (e.g. trait anxiety/anxiety disorder pathology) and anorexia nervosa development or maintenance was undertaken. Eight studies met inclusion criteria. Seven probed the association between anxiety and anorexia nervosa onset, and one assessed the association between anxiety and anorexia nervosa maintenance. Individuals with anorexia nervosa were more likely to report childhood anxiety compared to healthy individuals, but whether childhood anxiety explains unique variance in anorexia nervosa development is unclear. Current evidence does not support longitudinal associations between specific anxiety disorders (independently of other anxiety disorders) and subsequent anorexia nervosa onset, however anxiety disorder diagnosis in general may predict increased anorexia nervosa risk. The single study probing the association between anxiety and anorexia nervosa maintenance did not find evidence supporting a relationship. The quality of individual studies was fair to high, however the body of evidence was of low quality. Further research that minimises bias, allowing for strong conclusions concerning longitudinal associations between anxiety and subsequent anorexia nervosa outcomes, is required to inform anorexia nervosa aetiology. This in turn may promote improved prevention and treatment
Eating Disorders: Anorexia and Bulimia as Developmental Crises
Eating disorders are classified as developmental crises and typically develop during the adolescent years when youths face the identity versus role confusion psychosocial stage of development. Individuals struggling with anorexia nervosa or bulimia nervosa share characteristics similar to those found in a drug addiction. Social comparison theory may be used to explain the way individuals look to culture and media to examine whether their body images are acceptable. This body image comparison may result in an eating disorder, as can an environment where family dynamics are dysfunctional and therefore cannot cultivate healthy life stage development. Both anorexia nervosa and bulimia nervosa are best treated with an intervention process that involves the family
Complement C3 serum levels in anorexia nervosa: a potential biomarker for the severity of disease?
BackgroundAnorexia nervosa carries the highest mortality rate of any psychiatric disorder. Even the most critically ill anorexic patients may present with normal 'standard' laboratory values, underscoring the need for a new sensitive biomarker. The complement cascade, a major component of innate immunity, represents a driving force in the pathophysiology of multiple inflammatory disorders. The role of complement in anorexia nervosa remains poorly understood. The present study was designed to evaluate the role of complement C3 levels, the extent of complement activation and of complement hemolytic activity in serum, as potential new biomarkers for the severity of anorexia nervosa.Patients and methodsThis was a prospective cohort study on 14 patients with severe anorexia nervosa, as defined by a body mass index (BMI) <14 kg/m2. Serum samples were obtained in a biweekly manner until hospital discharge. A total of 17 healthy subjects with normal BMI values served as controls. The serum levels of complement C3, C3a, C5a, sC5b-9, and of the 50% hemolytic complement activity (CH50) were quantified and correlated with the BMIs of patients and control subjects.ResultsSerum C3 levels were significantly lower in patients with anorexia nervosa than in controls (median 3.7 (interquartile range (IQR) 2.5-4.9) vs 11.4 (IQR 8.9-13.7, P <0.001). In contrast, complement activation fragments and CH50 levels were not significantly different between the two groups. There was a strong correlation between index C3 levels and BMI (Spearman correlation coefficient = 0.71, P <0.001).ConclusionsComplement C3 serum levels may represent a sensitive new biomarker for monitoring the severity of disease in anorexia nervosa. The finding from this preliminary pilot study will require further investigation in future prospective large-scale multicenter trials
Anorexia nervosa: 30-year outcome
Background:
Little is known about the long-term outcome of anorexia nervosa.
Aims:
To study the 30-year outcome of adolescent-onset anorexia nervosa.
Method:
All 4291 individuals born in 1970 and attending eighth grade in 1985 in Gothenburg, Sweden were screened for anorexia nervosa. A total of 24 individuals (age cohort for anorexia nervosa) were pooled with 27 individuals with anorexia nervosa (identified through community screening) who were born in 1969 and 1971–1974. The 51 individuals with anorexia nervosa and 51 school- and gender-matched controls were followed prospectively and examined at mean ages of 16, 21, 24, 32 and 44. Psychiatric disorders, health-related quality of life and general outcome were assessed.
Results
At the 30-year follow-up 96% of participants agreed to participate. There was no mortality. Of the participants, 19% had an eating disorder diagnosis (6% anorexia nervosa, 2% binge-eating disorder, 11% other specified feeding or eating disorder); 38% had other psychiatric diagnoses; and 64% had full eating disorder symptom recovery, i.e. free of all eating disorder criteria for 6 consecutive months. During the elapsed 30 years, participants had an eating disorder for 10 years, on average, and 23% did not receive psychiatric treatment. Good outcome was predicted by later age at onset among individuals with adolescent-onset anorexia nervosa and premorbid perfectionism.
Conclusions:
This long-term follow-up study reflects the course of adolescent-onset anorexia nervosa and has shown a favourable outcome regarding mortality and full symptom recovery. However, one in five had a chronic eating disorder
The Neurobiology of Anorexia Nervosa
Anorexia nervosa is considered the most deadly psychological illness. Individuals with and recovered from anorexia nervosa experience numerous physical and mental health difficulties, and treatment outcomes remain unpromising. Anorexia nervosa is rare in the general population, but common among individuals with a first-degree relative with the disorder. In addition, the onset of anorexia nervosa is developmentally specific, which suggests a partly biological etiology. A better understanding of the biological and neurobiological etiology of anorexia nervosa is direly needed to inform new therapies and to identify individuals at risk for the disorder. This paper summarizes the research related to neurotransmitter abnormalities, aberrant brain activity, and genetic and epigenetic mechanisms that may contribute to the etiology of this deadly disorder
Applying neurobiology to the treatment of adults with anorexia nervosa
BackgroundAnorexia nervosa is a severe, biologically based brain disorder with significant medical complications. It is critical that new, effective treatments are developed to interrupt the persistent course of the illness due to the medical and psychological sequelae. Several psychosocial, behavioral and pharmacologic interventions have been investigated in adult anorexia nervosa; however, evidence shows that their impact is weak and treatment effects are generally small.MethodThis paper describes a new neurobiological anorexia nervosa model that shifts focus from solely external influences, such as social and family, to include internal influences that integrate genetic and neurobiological contributions, across the age span. The model serves as a theoretical structure for a new, five-day treatment, outlined in this paper, targeting anorexia nervosa temperament, which integrates neurobiological dimensions into evidence-based treatment interventions. The treatment is in two phases. Phase I is a five day, 40 hour treatment for anorexia nervosa adults. Phase II is the follow-up and is currently being developed.ResultsPreliminary qualitative acceptability data on 37 adults with anorexia nervosa and 60 supports (e.g., spouses, parents, aunts, friends, partners, children of anorexia nervosa adults) are promising from Phase I. Clients with anorexia nervosa and their supports report that learning neurobiological facts improved their understanding of the illness and helped equip them with better tools to manage anorexia nervosa traits and symptoms. In addition, nutritional knowledge changed significantly.ConclusionsThis is the first neurobiologically based, five-day treatment for adults with anorexia nervosa and their supports. It is a new model that outlines underlying genetic and neurobiological contributions to anorexia nervosa that serves as a foundation to treat both traits and symptoms. Preliminary qualitative findings are promising, with both clients and supports reporting that the neurobiological treatment approach helped them better understand the illness, while better conceptualizing how to respond to their traits and manage their symptoms. Data in Phase I shows promise as a neurobiologically based intervention for anorexia nervosa, and it serves as a foundation for the development of Phase II. Evidence of ongoing program efficacy will be described as data are reported on Phase II.Trial registrationNCT NCT02852538 Registered 1 August 2016
In Response: A Discussion of Bulimia as a Masturbatory Equivalent
My research and that of my colleagues in the psychodynamic cause, structure and treatment of patients with bulimic anorexia nervosa correlates with and confirms the hypotheses presented by Levin ( 1) that bulimic symptoms may represent a masturbatory equivalent.
In our recently published book, Fear of Being Fat: The Treatment of Anorexia Nervosa and Bulimia (2) we confirmed Sperling\u27s findings (3) that unresolved preoedipal fixations to the mother contribute to difficulties in psychosexual development and that anorexic girls and boys displace sexual and masturbatory conflicts from the genitals to the mouth
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