Anorexia Nervosa
Disease Details
Family Health Simplified
- Description
- Anorexia nervosa is a severe mental health disorder characterized by extreme fear of gaining weight and a distorted body image, leading to restricted food intake and dangerous weight loss.
- Type
- Anorexia nervosa is a type of eating disorder. Its genetic transmission is not fully understood, but it is believed to be polygenic, meaning multiple genes may contribute to the risk of developing the condition. Genetic factors combined with environmental influences play a role in its onset.
- Signs And Symptoms
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Anorexia nervosa is an eating disorder characterized by attempts to lose weight by way of starvation. A person with anorexia nervosa may exhibit a number of signs and symptoms, the type and severity of which may vary and be present but not readily apparent. Though anorexia is typically recognized by the physical manifestations of the illness, it is a mental disorder that can be present at any weight.
Anorexia nervosa, and the associated malnutrition that results from self-imposed starvation, can cause complications in every major organ system in the body. Hypokalemia, a drop in the level of potassium in the blood, is a sign of anorexia nervosa. A significant drop in potassium can cause abnormal heart rhythms, constipation, fatigue, muscle damage, and paralysis.Signs and symptoms may be classified in various categories including: physical, cognitive, affective, behavioral and perceptual: - Prognosis
- AN has the highest mortality rate of any psychological disorder. The mortality rate is 11 to 12 times greater than in the general population, and the suicide risk is 56 times higher. Half of women with AN achieve a full recovery, while an additional 20–30% may partially recover. Not all people with anorexia recover completely: about 20% develop anorexia nervosa as a chronic disorder. If anorexia nervosa is not treated, serious complications such as heart conditions and kidney failure can arise and eventually lead to death. The average number of years from onset to remission of AN is seven for women and three for men. After ten to fifteen years, 70% of people no longer meet the diagnostic criteria, but many still continue to have eating-related problems.Alexithymia (inability to identify and describe one's own emotions) influences treatment outcome. Recovery is also viewed on a spectrum rather than black and white. According to the Morgan-Russell criteria, individuals can have a good, intermediate, or poor outcome. Even when a person is classified as having a "good" outcome, weight only has to be within 15% of average, and normal menstruation must be present in females. The good outcome also excludes psychological health. Recovery for people with anorexia nervosa is undeniably positive, but recovery does not mean a return to normal.
- Onset
- Anorexia nervosa typically has an onset during adolescence, most commonly between ages 14 and 18. However, it can also occur in adulthood.
- Prevalence
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Anorexia nervosa is a serious eating disorder characterized by an intense fear of gaining weight and a distorted body image, leading to severe restriction of food intake. The prevalence of anorexia nervosa varies by demographic factors such as age, gender, and geographic location.
In general, the lifetime prevalence of anorexia nervosa is estimated to be around 0.9% for women and 0.3% for men. It is most commonly diagnosed in adolescents and young adults, although it can occur at any age. The disorder is more frequently observed in Western countries, but it is increasingly recognized in other regions of the world as well.
Anorexia nervosa has a significant impact on physical and mental health, and early intervention and treatment are crucial for improving outcomes. - Epidemiology
- Anorexia is estimated to occur in 0.9% to 4.3% of women and 0.2% to 0.3% of men in Western countries at some point in their life. About 0.4% of young females are affected in a given year and it is estimated to occur three to ten times less commonly in males. Rates in most of the developing world are unclear. Often it begins during the teen years or young adulthood. Medical students are a high risk group, with an overall estimated prevalence of 10.4% globally.The lifetime rate of atypical anorexia nervosa, a form of ED-NOS in which the person loses a significant amount of weight and is at risk for serious medical complications despite having a higher body-mass index, is much higher, at 5–12%. Additionally, a UCSF study showed severity of illness is independent of current BMI, and "patients with large, rapid, or long-duration of weight loss were more severely ill regardless of their current weight."While anorexia became more commonly diagnosed during the 20th century it is unclear if this was due to an increase in its frequency or simply better diagnosis. Most studies show that since at least 1970 the incidence of AN in adult women is fairly constant, while there is some indication that the incidence may have been increasing for girls aged between 14 and 20.
- Intractability
- Anorexia nervosa can be challenging to treat and may sometimes appear intractable due to its complex psychological, biological, and social components. However, it is not inherently intractable; with appropriate treatment involving medical, nutritional, and psychological interventions, many individuals can recover. Long-term support and therapy are often needed to manage and overcome the condition effectively.
- Disease Severity
- Disease severity for anorexia nervosa can vary widely. It ranges from mild cases with minimal weight loss and minor social or psychological impairment to severe cases that can lead to life-threatening physical complications such as electrolyte imbalances, cardiac issues, and severe malnutrition. The impact also includes significant psychological distress and potential long-term health consequences if not treated adequately.
- Healthcare Professionals
- Disease Ontology ID - DOID:8689
- Pathophysiology
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Anorexia nervosa is a psychological and potentially life-threatening eating disorder characterized by self-imposed starvation and excessive weight loss. Pathophysiologically, it involves several interconnected systems:
1. **Neurobiological Factors:** Changes in brain structure and function, particularly in areas controlling appetite and emotion, such as the hypothalamus and the limbic system. Abnormal levels of neurotransmitters like serotonin, dopamine, and norepinephrine play a role.
2. **Hormonal Dysregulation:** Disruptions in hormone levels, including leptin, ghrelin, and cortisol, affect hunger, stress responses, and metabolism. Reduced thyroid function (hypothyroidism), amenorrhea (cessation of menstrual periods), and decreased levels of sex hormones are common.
3. **Metabolic Changes:** Prolonged malnutrition leads to reduced basal metabolic rate. Electrolyte imbalances, hypoglycemia, and deficiencies in essential vitamins and minerals occur. The body adapts by breaking down muscles and organs for energy.
4. **Cardiovascular Issues:** Bradycardia (slow heart rate), hypotension (low blood pressure), and arrhythmias (irregular heart rhythms) due to electrolyte imbalances, especially low potassium.
5. **Gastrointestinal Problems:** Gastroparesis (delayed stomach emptying), constipation, and imbalances in gut microbiota due to reduced food intake.
Anorexia nervosa is complex, involving psychological, genetic, and environmental factors creating a multifaceted pathophysiological condition. - Carrier Status
- Anorexia nervosa is not associated with a carrier status as it is a mental health disorder rather than a genetic disease transmitted by carriers. It involves severe restriction of food intake, an intense fear of gaining weight, and a distorted body image. Although genetic factors may contribute to the risk of developing anorexia nervosa, carrier status is not applicable.
- Mechanism
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Anorexia nervosa is a psychiatric disorder characterized by severe weight loss due to self-imposed starvation and an intense fear of gaining weight. The mechanisms and molecular mechanisms of anorexia nervosa involve a complex interplay of genetic, biological, and environmental factors.
### Mechanism:
1. **Psychological Factors:** Distorted body image, obsessive fear of weight gain, and low self-esteem.
2. **Environmental Factors:** Sociocultural pressures, family dynamics, and stressful life events.
3. **Genetic Factors:** Family history of eating disorders, depression, or anxiety can increase risk.
### Molecular Mechanisms:
1. **Neurotransmitter Imbalances:** Dysregulation of serotonin, dopamine, and norepinephrine, which are crucial in mood and appetite regulation.
2. **Hypothalamic-Pituitary-Adrenal (HPA) Axis Dysregulation:** Chronic stress and starvation can affect the HPA axis, altering cortisol levels and contributing to anxiety and depression.
3. **Brain-Derived Neurotrophic Factor (BDNF):** Abnormal levels of BDNF, which plays a role in neural growth and function, have been observed in patients with anorexia nervosa.
4. **Genetic Polymorphisms:** Variations in genes such as those coding for brain-derived neurotrophic factor (BDNF), the serotonin transporter, and various opioid receptors.
5. **Epigenetic Changes:** Starvation and stress may lead to epigenetic modifications that affect gene expression related to appetite and mood regulation.
These mechanisms interact in a complex manner, contributing to the development and persistence of anorexia nervosa. - Treatment
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There is no conclusive evidence that any particular treatment for anorexia nervosa works better than others.Treatment for anorexia nervosa tries to address three main areas.
Restoring the person to a healthy weight;
Treating the psychological disorders related to the illness;
Reducing or eliminating behaviors or thoughts that originally led to the disordered eating.In some clinical settings a specific body image intervention is performed to reduce body dissatisfaction and body image disturbance. Although restoring the person's weight is the primary task at hand, optimal treatment also includes and monitors behavioral change in the individual as well. There is some evidence that hospitalization might adversely affect long term outcome, but sometimes is necessary. Psychotherapy for individuals with AN is challenging as they may value being thin and may seek to maintain control and resist change. Initially, developing a desire to change is fundamental. Despite no evidence for better treatment in adults patients, research stated that family based therapy is the primary choice for adolescents with AN. - Compassionate Use Treatment
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Compassionate use treatments and off-label or experimental treatments for anorexia nervosa can be of interest when conventional treatments are ineffective. Some investigational approaches include:
1. **Deep Brain Stimulation (DBS)**: This neurosurgical procedure is being studied for its potential to modulate neural circuits involved in anorexia nervosa.
2. **Repetitive Transcranial Magnetic Stimulation (rTMS)**: An experimental non-invasive method aimed at altering brain activity, which might help in reducing symptoms.
3. **Medication Trials**: Some drugs, such as Olanzapine and other atypical antipsychotics, are used off-label to help manage symptoms due to their effects on appetite and mood.
4. **Psychotherapy Innovations**: Enhanced cognitive-behavioral therapy (CBT-E) and Maudsley Anorexia Nervosa Treatment for Adults (MANTRA) are specialized therapeutic approaches currently under exploration.
5. **Hormonal Treatments**: Research is ongoing into the use of hormonal therapies, such as oxytocin, to potentially assist in promoting social bonding and reducing anxiety.
These treatments are typically considered when patients do not respond to standard therapies and are closely monitored by healthcare professionals. - Lifestyle Recommendations
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For anorexia nervosa, lifestyle recommendations include:
1. **Balanced Nutrition**: Gradually incorporating a balanced diet with the help of a nutritionist to ensure all necessary nutrients are consumed.
2. **Regular Eating Schedule**: Establishing a consistent meal routine to stabilize eating patterns.
3. **Hydration**: Drinking plenty of water and staying adequately hydrated.
4. **Avoiding Triggers**: Steering clear of activities or environments that may trigger unhealthy eating habits or body image concerns.
5. **Physical Activity**: Engaging in moderate and enjoyable physical activities to improve mental and physical health, under professional guidance.
6. **Sleep Hygiene**: Ensuring adequate sleep to support overall health and emotional well-being.
7. **Therapeutic Support**: Participating in therapy sessions (e.g., cognitive-behavioral therapy) to address underlying psychological issues.
8. **Support Networks**: Seeking support from family, friends, or support groups to provide encouragement and understanding.
Combining these lifestyle changes with professional medical support can improve outcomes for individuals with anorexia nervosa. - Medication
- Pharmaceuticals have limited benefit for anorexia itself. There is a lack of good information from which to make recommendations concerning the effectiveness of antidepressants in treating anorexia. Administration of olanzapine has been shown to result in a modest but statistically significant increase in body weight of anorexia nervosa patients.
- Repurposable Drugs
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Currently, there are no FDA-approved drugs specifically for the treatment of anorexia nervosa. However, some repurposable drugs that have been explored in clinical settings include:
1. **Olanzapine**: An antipsychotic used primarily to treat schizophrenia and bipolar disorder, which has shown some efficacy in weight gain and reducing obsessional thinking in anorexia nervosa patients.
2. **Fluoxetine**: An SSRI commonly used for depression and OCD, which may help with underlying mood symptoms and prevent relapse in anorexia nervosa patients who have restored a healthy weight.
3. **Cyproheptadine**: An antihistamine with appetite-stimulating properties that has been used off-label to aid weight gain.
These medications are used as part of a comprehensive treatment plan, including psychotherapy and nutritional rehabilitation. Any medication use should be closely monitored by healthcare professionals due to potential side effects and the complex nature of the eating disorder. - Metabolites
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In individuals with anorexia nervosa, several metabolites can exhibit significant alterations due to severe malnutrition and the body's consequent metabolic adaptions. These may include:
1. **Ketone Bodies**: Elevated levels due to increased fat metabolism.
2. **Cortisol**: Often elevated due to stress and starvation.
3. **Amino Acids**: Altered levels, some may decrease due to muscle catabolism.
4. **Electrolytes**: Imbalances, such as hypokalemia (low potassium) and hyponatremia (low sodium).
5. **Thyroid Hormones**: Reduced levels of T3 (triiodothyronine) and T4 (thyroxine) hormones.
6. **Leptin**: Lower levels due to decreased fat mass.
These changes can be detected through various biochemical tests, providing insight into the physiological disruptions caused by anorexia nervosa. - Nutraceuticals
- For anorexia nervosa, the role of nutraceuticals is not well-established and more research is required. Treatment typically focuses on nutritional rehabilitation, psychotherapy, and medical monitoring. Nutraceuticals may sometimes be considered as part of a broader treatment plan, but they should not replace traditional treatments. Always consult a healthcare provider before using nutraceuticals.
- Peptides
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Anorexia nervosa is a serious eating disorder characterized by self-imposed starvation and excessive weight loss. Regarding peptides, research has indicated that various peptides play roles in appetite regulation and the pathophysiology of anorexia nervosa. Noteworthy peptides include:
1. **Ghrelin**: Typically increases appetite; however, in anorexia nervosa patients, there's often resistance to its appetite-stimulating effects.
2. **Leptin**: Typically decreases appetite; its levels are usually abnormally low in individuals with anorexia nervosa due to low body fat, potentially contributing to the regulation of starvation responses.
3. **Peptide YY (PYY)**: Often elevated in anorexia nervosa, which may suppress appetite and contribute to reduced food intake.
These peptides’ dysfunction or altered levels could partly explain the persistent anorexia and other metabolic abnormalities observed in anorexia nervosa. Further research could provide deeper insights into their specific roles and potential therapeutic targets.