Anorexia Nervosa

Overview

Definition

Anorexia nervosa is an eating disorder characterized by self-imposed starvation and inappropriate dietary habits due to an intense fear of weight gain and disturbed perception Perception The process by which the nature and meaning of sensory stimuli are recognized and interpreted. Psychiatric Assessment of body shape and weight.

Epidemiology

• Common in young women aged 15–25 years 
• Prevalence Prevalence The total number of cases of a given disease in a specified population at a designated time. It is differentiated from incidence, which refers to the number of new cases in the population at a given time. Measures of Disease Frequency: approximately 1%
• Women:men ratio: 3:1
• Patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship in professions that stress thinness, such as ballet dancers, athletes, and models, are frequently affected.
• Highest death rate of any mental illness (5%–20%)

Pathophysiology

Complex interaction between biological, psychological, and social factors:

• Sociocultural factors:
  • Media influence on excessive need to be thin
  • Cultural norms, excessively emphasizing thinness
• Genetic factors: anorexia nervosa more likely in monozygotic than dizygotic twins Dizygotic twins Result from 2 separate eggs fertilized by 2 separate sperm; share approximately 50% of the genetic material Multiple Pregnancy
• Environmental factors: Interpersonal relationships may affect eating habits.
• Psychological factors:
  • Low self-esteem
  • Perfectionism Perfectionism A personality trait characterized by a person’s striving for flawlessness and setting excessively high performance standards, accompanied by overly critical self-evaluations and concerns regarding others’ evaluations. Cluster C Personality Disorders
  • Impulsivity Impulsivity Attention Deficit Hyperactivity Disorder
  • OCD OCD Obsessive-compulsive disorder (OCD) is a condition characterized by obsessions (recurring and intrusive thoughts, urges, or images) and/or compulsions (repetitive actions the person is compelled to perform) that are time-consuming and associated with functional impairment. Obsessive-compulsive Disorder (OCD)
• Neurobiological factors:
  • Abnormalities in brain Brain The part of central nervous system that is contained within the skull (cranium). Arising from the neural tube, the embryonic brain is comprised of three major parts including prosencephalon (the forebrain); mesencephalon (the midbrain); and rhombencephalon (the hindbrain). The developed brain consists of cerebrum; cerebellum; and other structures in the brain stem. Nervous System: Anatomy, Structure, and Classification areas involved in appetite and habitual behavior:
    • Corticolimbic circuits Corticolimbic circuits Bulimia Nervosa
    • Dorsal striatum Striatum Striped gray matter and white matter consisting of the neostriatum and paleostriatum (globus pallidus). It is located in front of and lateral to the thalamus in each cerebral hemisphere. The gray substance is made up of the caudate nucleus and the lentiform nucleus (the latter consisting of the globus pallidus and putamen). The white matter is the internal capsule. Basal Ganglia: Anatomy
  • Abnormalities in neurotransmitters:
    • Dopamine Dopamine One of the catecholamine neurotransmitters in the brain. It is derived from tyrosine and is the precursor to norepinephrine and epinephrine. Dopamine is a major transmitter in the extrapyramidal system of the brain, and important in regulating movement. Receptors and Neurotransmitters of the CNS
    • Serotonin Serotonin A biochemical messenger and regulator, synthesized from the essential amino acid l-tryptophan. In humans it is found primarily in the central nervous system, gastrointestinal tract, and blood platelets. Serotonin mediates several important physiological functions including neurotransmission, gastrointestinal motility, hemostasis, and cardiovascular integrity. Receptors and Neurotransmitters of the CNS

Clinical Presentation

Anorexia nervosa affects almost all body systems and can present with a variety of symptoms and signs.

Symptoms

• Difficulty concentrating and making decisions
• Depressed mood and anxiety Anxiety Feelings or emotions of dread, apprehension, and impending disaster but not disabling as with anxiety disorders. Generalized Anxiety Disorder 
• Headaches
• Fainting or dizzy spells
• Lethargy Lethargy A general state of sluggishness, listless, or uninterested, with being tired, and having difficulty concentrating and doing simple tasks. It may be related to depression or drug addiction. Hyponatremia
• Cold intolerance (decreased thyroid Thyroid The thyroid gland is one of the largest endocrine glands in the human body. The thyroid gland is a highly vascular, brownish-red gland located in the visceral compartment of the anterior region of the neck. Thyroid Gland: Anatomy hormones Hormones Hormones are messenger molecules that are synthesized in one part of the body and move through the bloodstream to exert specific regulatory effects on another part of the body. Hormones play critical roles in coordinating cellular activities throughout the body in response to the constant changes in both the internal and external environments. Hormones: Overview and Types)
• Epigastric pain Epigastric pain Mallory-Weiss Syndrome (Mallory-Weiss Tear), gastroparesis Gastroparesis Chronic delayed gastric emptying. Gastroparesis may be caused by motor dysfunction or paralysis of stomach muscles or may be associated with other systemic diseases such as diabetes mellitus. Malabsorption and Maldigestion, constipation Constipation Constipation is common and may be due to a variety of causes. Constipation is generally defined as bowel movement frequency < 3 times per week. Patients who are constipated often strain to pass hard stools. The condition is classified as primary (also known as idiopathic or functional constipation) or secondary, and as acute or chronic. Constipation

Signs

• Emaciation
• Hypotension Hypotension Hypotension is defined as low blood pressure, specifically < 90/60 mm Hg, and is most commonly a physiologic response. Hypotension may be mild, serious, or life threatening, depending on the cause. Hypotension, bradycardia Bradycardia Bradyarrhythmia is a rhythm in which the heart rate is less than 60/min. Bradyarrhythmia can be physiologic, without symptoms or hemodynamic change. Pathologic bradyarrhythmia results in reduced cardiac output and hemodynamic instability causing syncope, dizziness, or dyspnea. Bradyarrhythmias, arrhythmias
• Hypothermia Hypothermia Hypothermia can be defined as a drop in the core body temperature below 35°C (95°F) and is classified into mild, moderate, severe, and profound forms based on the degree of temperature decrease. Hypothermia
• Dry skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions, dehydration Dehydration The condition that results from excessive loss of water from a living organism. Volume Depletion and Dehydration, lanugo (body hair/thin hair)
• Breast atrophy Atrophy Decrease in the size of a cell, tissue, organ, or multiple organs, associated with a variety of pathological conditions such as abnormal cellular changes, ischemia, malnutrition, or hormonal changes. Cellular Adaptation
• Physical signs consistent with self-induced vomiting Vomiting The forcible expulsion of the contents of the stomach through the mouth. Hypokalemia:
  • Swelling Swelling Inflammation of the salivary glands Salivary glands The salivary glands are exocrine glands positioned in and around the oral cavity. These glands are responsible for secreting saliva into the mouth, which aids in digestion. There are 3 major paired salivary glands: the sublingual, submandibular, and parotid glands. Salivary Glands: Anatomy
  • Dental caries
  • Scars or calluses on the hand Hand The hand constitutes the distal part of the upper limb and provides the fine, precise movements needed in activities of daily living. It consists of 5 metacarpal bones and 14 phalanges, as well as numerous muscles innervated by the median and ulnar nerves. Hand: Anatomy from contact with the teeth Teeth Normally, an adult has 32 teeth: 16 maxillary and 16 mandibular. These teeth are divided into 4 quadrants with 8 teeth each. Each quadrant consists of 2 incisors (dentes incisivi), 1 canine (dens caninus), 2 premolars (dentes premolares), and 3 molars (dentes molares). Teeth are composed of enamel, dentin, and dental cement. Teeth: Anatomy (Russell sign)
• Edema Edema Edema is a condition in which excess serous fluid accumulates in the body cavity or interstitial space of connective tissues. Edema is a symptom observed in several medical conditions. It can be categorized into 2 types, namely, peripheral (in the extremities) and internal (in an organ or body cavity). Edema:
  • Periorbital Periorbital Orbital and Preseptal Cellulitis
  • Peripheral (extremities) 
  • Periabdominal ( ascites Ascites Ascites is the pathologic accumulation of fluid within the peritoneal cavity that occurs due to an osmotic and/or hydrostatic pressure imbalance secondary to portal hypertension (cirrhosis, heart failure) or non-portal hypertension (hypoalbuminemia, malignancy, infection). Ascites)
• Amenorrhea Amenorrhea Absence of menstruation. Congenital Malformations of the Female Reproductive System 

Lab findings

• Nutritional deficiency:
  • ↓ Iron Iron A metallic element with atomic symbol fe, atomic number 26, and atomic weight 55. 85. It is an essential constituent of hemoglobins; cytochromes; and iron-binding proteins. It plays a role in cellular redox reactions and in the transport of oxygen. Trace Elements
  • ↓ Folate Folate Folate and vitamin B12 are 2 of the most clinically important water-soluble vitamins. Deficiencies can present with megaloblastic anemia, GI symptoms, neuropsychiatric symptoms, and adverse pregnancy complications, including neural tube defects. Folate and Vitamin B12
  • ↓ Vitamin B₁₂ 
  • ↓ Vitamin D Vitamin D A vitamin that includes both cholecalciferols and ergocalciferols, which have the common effect of preventing or curing rickets in animals. It can also be viewed as a hormone since it can be formed in skin by action of ultraviolet rays upon the precursors, 7-dehydrocholesterol and ergosterol, and acts on vitamin D receptors to regulate calcium in opposition to parathyroid hormone. Fat-soluble Vitamins and their Deficiencies
• Anemia Anemia Anemia is a condition in which individuals have low Hb levels, which can arise from various causes. Anemia is accompanied by a reduced number of RBCs and may manifest with fatigue, shortness of breath, pallor, and weakness. Subtypes are classified by the size of RBCs, chronicity, and etiology. Anemia: Overview and Types secondary to nutritional deficiencies
• Cytopenias Cytopenias IPEX Syndrome
• Serum electrolyte abnormalities due to recurrent vomiting Vomiting The forcible expulsion of the contents of the stomach through the mouth. Hypokalemia:
  • ↓ Potassium Potassium An element in the alkali group of metals with an atomic symbol k, atomic number 19, and atomic weight 39. 10. It is the chief cation in the intracellular fluid of muscle and other cells. Potassium ion is a strong electrolyte that plays a significant role in the regulation of fluid volume and maintenance of the water-electrolyte balance. Hyperkalemia
  • ↓ Calcium Calcium A basic element found in nearly all tissues. It is a member of the alkaline earth family of metals with the atomic symbol ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes. Electrolytes
  • ↓ Magnesium Magnesium A metallic element that has the atomic symbol mg, atomic number 12, and atomic weight 24. 31. It is important for the activity of many enzymes, especially those involved in oxidative phosphorylation. Electrolytes
  • ↓ Phosphate Phosphate Inorganic salts of phosphoric acid. Electrolytes
• Disturbances in albumin Albumin Serum albumin from humans. It is an essential carrier of both endogenous substances, such as fatty acids and bilirubin, and of xenobiotics in the blood. Liver Function Tests (low albumin Albumin Serum albumin from humans. It is an essential carrier of both endogenous substances, such as fatty acids and bilirubin, and of xenobiotics in the blood. Liver Function Tests indicate a chronically low protein intake)
• Elevated liver Liver The liver is the largest gland in the human body. The liver is found in the superior right quadrant of the abdomen and weighs approximately 1.5 kilograms. Its main functions are detoxification, metabolism, nutrient storage (e.g., iron and vitamins), synthesis of coagulation factors, formation of bile, filtration, and storage of blood. Liver: Anatomy enzymes Enzymes Enzymes are complex protein biocatalysts that accelerate chemical reactions without being consumed by them. Due to the body’s constant metabolic needs, the absence of enzymes would make life unsustainable, as reactions would occur too slowly without these molecules. Basics of Enzymes
• Urinalysis Urinalysis Examination of urine by chemical, physical, or microscopic means. Routine urinalysis usually includes performing chemical screening tests, determining specific gravity, observing any unusual color or odor, screening for bacteriuria, and examining the sediment microscopically. Urinary Tract Infections (UTIs) in Children showing increased sedimentation rate
• Secondary amenorrhea Amenorrhea Absence of menstruation. Congenital Malformations of the Female Reproductive System:
  • ↓ Luteinizing hormone ( LH LH A major gonadotropin secreted by the adenohypophysis. Luteinizing hormone regulates steroid production by the interstitial cells of the testis and the ovary. The preovulatory luteinizing hormone surge in females induces ovulation, and subsequent luteinization of the follicle. Luteinizing hormone consists of two noncovalently linked subunits, alpha and beta. Within a species, the alpha subunit is common in the three pituitary glycoprotein hormones (TSH, LH, and FSH), but the beta subunit is unique and confers its biological specificity. Menstrual Cycle) 
  • ↓ Follicle-stimulating hormone ( FSH FSH A major gonadotropin secreted by the adenohypophysis. Follicle-stimulating hormone stimulates gametogenesis and the supporting cells such as the ovarian granulosa cells, the testicular sertoli cells, and leydig cells. Fsh consists of two noncovalently linked subunits, alpha and beta. Within a species, the alpha subunit is common in the three pituitary glycoprotein hormones (TSH, LH, and FSH), but the beta subunit is unique and confers its biological specificity. Menstrual Cycle)
• Hypercholesterolemia Hypercholesterolemia A condition with abnormally high levels of cholesterol in the blood. It is defined as a cholesterol value exceeding the 95th percentile for the population. Lipid Disorders
• Disruption of thyroid Thyroid The thyroid gland is one of the largest endocrine glands in the human body. The thyroid gland is a highly vascular, brownish-red gland located in the visceral compartment of the anterior region of the neck. Thyroid Gland: Anatomy hormone level

Clinical imaging

• ECG ECG An electrocardiogram (ECG) is a graphic representation of the electrical activity of the heart plotted against time. Adhesive electrodes are affixed to the skin surface allowing measurement of cardiac impulses from many angles. The ECG provides 3-dimensional information about the conduction system of the heart, the myocardium, and other cardiac structures. Electrocardiogram (ECG): shows sinus bradycardia Sinus bradycardia Bradyarrhythmias
• DEXA DEXA Osteoporosis scan: decreased bone Bone Bone is a compact type of hardened connective tissue composed of bone cells, membranes, an extracellular mineralized matrix, and central bone marrow. The 2 primary types of bone are compact and spongy. Bones: Structure and Types mineral density (due to insufficient calcium Calcium A basic element found in nearly all tissues. It is a member of the alkaline earth family of metals with the atomic symbol ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes. Electrolytes, phosphate Phosphate Inorganic salts of phosphoric acid. Electrolytes, and vitamin D Vitamin D A vitamin that includes both cholecalciferols and ergocalciferols, which have the common effect of preventing or curing rickets in animals. It can also be viewed as a hormone since it can be formed in skin by action of ultraviolet rays upon the precursors, 7-dehydrocholesterol and ergosterol, and acts on vitamin D receptors to regulate calcium in opposition to parathyroid hormone. Fat-soluble Vitamins and their Deficiencies in diet) 
• Imaging may be required to rule out malignant causes of weight loss Weight loss Decrease in existing body weight. Bariatric Surgery.

Complications

• Myocardial atrophy Atrophy Decrease in the size of a cell, tissue, organ, or multiple organs, associated with a variety of pathological conditions such as abnormal cellular changes, ischemia, malnutrition, or hormonal changes. Cellular Adaptation
• Mitral valve Mitral valve The valve between the left atrium and left ventricle of the heart. Heart: Anatomy prolapse
• Pericardial effusion Pericardial effusion Fluid accumulation within the pericardium. Serous effusions are associated with pericardial diseases. Hemopericardium is associated with trauma. Lipid-containing effusion (chylopericardium) results from leakage of thoracic duct. Severe cases can lead to cardiac tamponade. Pericardial Effusion and Cardiac Tamponade
• Osteoporosis Osteoporosis Osteoporosis refers to a decrease in bone mass and density leading to an increased number of fractures. There are 2 forms of osteoporosis: primary, which is commonly postmenopausal or senile; and secondary, which is a manifestation of immobilization, underlying medical disorders, or long-term use of certain medications. Osteoporosis
• Gastroparesis Gastroparesis Chronic delayed gastric emptying. Gastroparesis may be caused by motor dysfunction or paralysis of stomach muscles or may be associated with other systemic diseases such as diabetes mellitus. Malabsorption and Maldigestion
• Amenorrhea Amenorrhea Absence of menstruation. Congenital Malformations of the Female Reproductive System, infertility Infertility Infertility is the inability to conceive in the context of regular intercourse. The most common causes of infertility in women are related to ovulatory dysfunction or tubal obstruction, whereas, in men, abnormal sperm is a common cause. Infertility ( functional hypothalamic amenorrhea Functional Hypothalamic Amenorrhea Secondary Amenorrhea due to low levels of LH LH A major gonadotropin secreted by the adenohypophysis. Luteinizing hormone regulates steroid production by the interstitial cells of the testis and the ovary. The preovulatory luteinizing hormone surge in females induces ovulation, and subsequent luteinization of the follicle. Luteinizing hormone consists of two noncovalently linked subunits, alpha and beta. Within a species, the alpha subunit is common in the three pituitary glycoprotein hormones (TSH, LH, and FSH), but the beta subunit is unique and confers its biological specificity. Menstrual Cycle and FSH FSH A major gonadotropin secreted by the adenohypophysis. Follicle-stimulating hormone stimulates gametogenesis and the supporting cells such as the ovarian granulosa cells, the testicular sertoli cells, and leydig cells. Fsh consists of two noncovalently linked subunits, alpha and beta. Within a species, the alpha subunit is common in the three pituitary glycoprotein hormones (TSH, LH, and FSH), but the beta subunit is unique and confers its biological specificity. Menstrual Cycle)
• Growth disturbances

Diagnosis

Criteria

Diagnosis is clinical, based on observed criteria:

• Restricted dietary habits resulting in significantly low body weight
• Intense fear of gaining weight
• Perceived disturbance in body weight and shape
• Symptoms must be present for at least 3 months.

Subtypes

• Restricting type: characterized by excessive starvation ( weight loss Weight loss Decrease in existing body weight. Bariatric Surgery is accomplished primarily through dieting, fasting, and/or excessive exercise) 
• Binge-eating/ purging Purging Bulimia Nervosa type: characterized by the use of drugs ( laxatives Laxatives Laxatives are medications used to promote defecation. Most often, laxatives are used to treat constipation or for bowel preparation for certain procedures. There are 4 main classes of laxatives: bulk-forming, stimulant, osmotic, and emollient. Laxatives, diuretics Diuretics Agents that promote the excretion of urine through their effects on kidney function. Heart Failure and Angina Medication), induced vomiting Vomiting The forcible expulsion of the contents of the stomach through the mouth. Hypokalemia, and excessive exercise as a means to reduce weight 

Severity

• Mild: BMI BMI An indicator of body density as determined by the relationship of body weight to body height. Bmi=weight (kg)/height squared (m2). Bmi correlates with body fat (adipose tissue). Their relationship varies with age and gender. For adults, bmi falls into these categories: below 18. 5 (underweight); 18. 5-24. 9 (normal); 25. 0-29. 9 (overweight); 30. 0 and above (obese). Obesity 17–18.49 kg/m²
• Moderate: BMI BMI An indicator of body density as determined by the relationship of body weight to body height. Bmi=weight (kg)/height squared (m2). Bmi correlates with body fat (adipose tissue). Their relationship varies with age and gender. For adults, bmi falls into these categories: below 18. 5 (underweight); 18. 5-24. 9 (normal); 25. 0-29. 9 (overweight); 30. 0 and above (obese). Obesity 16–16.99 kg/m²
• Severe: BMI BMI An indicator of body density as determined by the relationship of body weight to body height. Bmi=weight (kg)/height squared (m2). Bmi correlates with body fat (adipose tissue). Their relationship varies with age and gender. For adults, bmi falls into these categories: below 18. 5 (underweight); 18. 5-24. 9 (normal); 25. 0-29. 9 (overweight); 30. 0 and above (obese). Obesity 15–15.99 kg/m²
• Extreme: BMI BMI An indicator of body density as determined by the relationship of body weight to body height. Bmi=weight (kg)/height squared (m2). Bmi correlates with body fat (adipose tissue). Their relationship varies with age and gender. For adults, bmi falls into these categories: below 18. 5 (underweight); 18. 5-24. 9 (normal); 25. 0-29. 9 (overweight); 30. 0 and above (obese). Obesity < 15 kg/m²

Management and Prognosis

Management

Treatment involves a combination of psychotherapy Psychotherapy Psychotherapy is interpersonal treatment based on the understanding of psychological principles and mechanisms of mental disease. The treatment approach is often individualized, depending on the psychiatric condition(s) or circumstance. Psychotherapy and pharmacotherapy.

• Psychotherapy Psychotherapy Psychotherapy is interpersonal treatment based on the understanding of psychological principles and mechanisms of mental disease. The treatment approach is often individualized, depending on the psychiatric condition(s) or circumstance. Psychotherapy:
  • A comprehensive therapeutic approach is recommended. 
  • CBT is the mainstay of treatment.
  • Family therapy Family therapy A form of group psychotherapy. It involves treatment of more than one member of the family simultaneously in the same session. Psychotherapy is also recommended, especially for those patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship who reside with their families.
• Pharmacotherapy:
  • Limited role
  • Olanzapine Olanzapine A benzodiazepine derivative that binds serotonin receptors; muscarinic receptors; histamine h1 receptors; adrenergic alpha-1 receptors; and dopamine receptors. It is an antipsychotic agent used in the treatment of schizophrenia; bipolar disorder; and major depressive disorder; it may also reduce nausea and vomiting in patients undergoing chemotherapy. Second-Generation Antipsychotics may be indicated in some cases (helps patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship to gain weight) 
  • Antidepressants can also help patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship to gain weight (e.g., paroxetine Paroxetine A serotonin uptake inhibitor that is effective in the treatment of depression. Serotonin Reuptake Inhibitors and Similar Antidepressants or mirtazapine).

Consider hospitalizing patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship with:

• Heart rate Heart rate The number of times the heart ventricles contract per unit of time, usually per minute. Cardiac Physiology < 40/min
• Blood pressure < 80/60 mm Hg
• Cardiac dysrhythmia
• Cardiovascular, hepatic, or renal compromise requiring medical stabilization
• Severe dehydration Severe Dehydration Fluid Replacement Therapy in Children
• Serious medical complications of malnutrition Malnutrition Malnutrition is a clinical state caused by an imbalance or deficiency of calories and/or micronutrients and macronutrients. The 2 main manifestations of acute severe malnutrition are marasmus (total caloric insufficiency) and kwashiorkor (protein malnutrition with characteristic edema). Malnutrition in children in resource-limited countries (e.g., electrolyte imbalance, hypoglycemia Hypoglycemia Hypoglycemia is an emergency condition defined as a serum glucose level ≤ 70 mg/dL (≤ 3.9 mmol/L) in diabetic patients. In nondiabetic patients, there is no specific or defined limit for normal serum glucose levels, and hypoglycemia is defined mainly by its clinical features. Hypoglycemia, or syncope Syncope Syncope is a short-term loss of consciousness and loss of postural stability followed by spontaneous return of consciousness to the previous neurologic baseline without the need for resuscitation. The condition is caused by transient interruption of cerebral blood flow that may be benign or related to a underlying life-threatening condition. Syncope)
• Suicidal ideation Suicidal ideation A risk factor for suicide attempts and completions, it is the most common of all suicidal behavior, but only a minority of ideators engage in overt self-harm. Suicide with plan or attempt
• Body mass index Body mass index An indicator of body density as determined by the relationship of body weight to body height. Bmi=weight (kg)/height squared (m2). Bmi correlates with body fat (adipose tissue). Their relationship varies with age and gender. For adults, bmi falls into these categories: below 18. 5 (underweight); 18. 5-24. 9 (normal); 25. 0-29. 9 (overweight); 30. 0 and above (obese). Obesity < 15 kg/m² or ideal body weight < 70%

Refeeding syndrome Refeeding syndrome A condition of metabolic imbalance that is caused by complications of initially feeding a severely malnourished patient too aggressively. Usually occurring within the first 5 days of refeeding, this syndrome is characterized by water-electrolyte imbalance; glucose intolerance; cardiac arrhythmias; and diarrhea. Failure to Thrive:

• Constellation of metabolic disturbances that may occur due to refeeding of malnourished patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship who are persistently starved.
• Sudden increase in caloric intake causes an increase in insulin Insulin Insulin is a peptide hormone that is produced by the beta cells of the pancreas. Insulin plays a role in metabolic functions such as glucose uptake, glycolysis, glycogenesis, lipogenesis, and protein synthesis. Exogenous insulin may be needed for individuals with diabetes mellitus, in whom there is a deficiency in endogenous insulin or increased insulin resistance. Insulin production.
• Increase in insulin Insulin Insulin is a peptide hormone that is produced by the beta cells of the pancreas. Insulin plays a role in metabolic functions such as glucose uptake, glycolysis, glycogenesis, lipogenesis, and protein synthesis. Exogenous insulin may be needed for individuals with diabetes mellitus, in whom there is a deficiency in endogenous insulin or increased insulin resistance. Insulin causes a sudden shifting of fluid and electrolytes Electrolytes Electrolytes are mineral salts that dissolve in water and dissociate into charged particles called ions, which can be either be positively (cations) or negatively (anions) charged. Electrolytes are distributed in the extracellular and intracellular compartments in different concentrations. Electrolytes are essential for various basic life-sustaining functions. Electrolytes into cells.
• Marked electrolyte disturbances ( hypophosphatemia Hypophosphatemia A condition of an abnormally low level of phosphates in the blood. Bartter Syndrome), seizures Seizures A seizure is abnormal electrical activity of the neurons in the cerebral cortex that can manifest in numerous ways depending on the region of the brain affected. Seizures consist of a sudden imbalance that occurs between the excitatory and inhibitory signals in cortical neurons, creating a net excitation. The 2 major classes of seizures are focal and generalized. Seizures, delirium Delirium Delirium is a medical condition characterized by acute disturbances in attention and awareness. Symptoms may fluctuate during the course of a day and involve memory deficits and disorientation. Delirium, cardiac complications (cardiopulmonary failure), rhabdomyolysis Rhabdomyolysis Rhabdomyolysis is characterized by muscle necrosis and the release of toxic intracellular contents, especially myoglobin, into the circulation. Rhabdomyolysis
• Aggressive nutrition without good monitoring can be fatal.

Prognosis Prognosis A prediction of the probable outcome of a disease based on a individual’s condition and the usual course of the disease as seen in similar situations. Non-Hodgkin Lymphomas

• With timely treatment, most of the complications (except for osteoporosis Osteoporosis Osteoporosis refers to a decrease in bone mass and density leading to an increased number of fractures. There are 2 forms of osteoporosis: primary, which is commonly postmenopausal or senile; and secondary, which is a manifestation of immobilization, underlying medical disorders, or long-term use of certain medications. Osteoporosis) may be reversible.

• One of the highest mortality Mortality All deaths reported in a given population. Measures of Health Status rates among the psychiatric disorders
• Those with restricting type are less likely to recover than those with binge-eating/ purging Purging Bulimia Nervosa type.

Differential Diagnosis

• Bulimia Bulimia Eating an excess amount of food in a short period of time, as seen in the disorder of bulimia nervosa. It is caused by an abnormal craving for food, or insatiable hunger also known as ‘ox hunger’. Bulimia Nervosa nervosa: an anxiety-driven eating disorder defined by recurrent episodic binge eating Binge eating Binge eating is defined as consuming an amount of food in a specified amount of time (e.g., 1 hour) that greatly exceeds what most people would consume in that same amount of time. Binge Eating Disorder paired with recurrent inappropriate compensatory behavior Compensatory behavior Binge Eating Disorder (inducing vomiting Vomiting The forcible expulsion of the contents of the stomach through the mouth. Hypokalemia, laxative Laxative Agents that produce a soft formed stool, and relax and loosen the bowels, typically used over a protracted period, to relieve constipation. Hypokalemia abuse, excessive exercise). Patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship with this condition may have normal or even elevated BMI BMI An indicator of body density as determined by the relationship of body weight to body height. Bmi=weight (kg)/height squared (m2). Bmi correlates with body fat (adipose tissue). Their relationship varies with age and gender. For adults, bmi falls into these categories: below 18. 5 (underweight); 18. 5-24. 9 (normal); 25. 0-29. 9 (overweight); 30. 0 and above (obese). Obesity and are more likely to seek help. Treatment involves a combination of CBT and SSRIs SSRIs Serotonin Reuptake Inhibitors and Similar Antidepressants.
• Binge-eating disorder: an eating disorder marked by recurrent episodes of binge eating Binge eating Binge eating is defined as consuming an amount of food in a specified amount of time (e.g., 1 hour) that greatly exceeds what most people would consume in that same amount of time. Binge Eating Disorder without inappropriate compensatory behavior Compensatory behavior Binge Eating Disorder, resulting in fluctuating body weight. Episodes occur at least once a week for 3 months. Treatment consists of a combination of psychotherapy Psychotherapy Psychotherapy is interpersonal treatment based on the understanding of psychological principles and mechanisms of mental disease. The treatment approach is often individualized, depending on the psychiatric condition(s) or circumstance. Psychotherapy and pharmacotherapy.
• Rumination Rumination Regurgitation and re-chewing of previously swallowed food in ruminants. Rumination Disorder disorder: repeated regurgitation Regurgitation Gastroesophageal Reflux Disease (GERD) of food, which may be re-chewed, re-swallowed, or spit out, and which is not due to a general medical condition (e.g., GERD GERD Gastroesophageal reflux disease (GERD) occurs when the stomach acid frequently flows back into the esophagus. This backwash (acid reflux) can irritate the lining of the esophagus, causing symptoms such as retrosternal burning pain (heartburn). Gastroesophageal Reflux Disease (GERD)). Treatment involves multiple CBT techniques, including biofeedback Biofeedback The therapy technique of providing the status of one’s own autonomic nervous system function (e.g., skin temperature, heartbeats, brain waves) as visual or auditory feedback in order to self-control related conditions (e.g., hypertension, migraine headaches). Psychotherapy psychotherapy Psychotherapy Psychotherapy is interpersonal treatment based on the understanding of psychological principles and mechanisms of mental disease. The treatment approach is often individualized, depending on the psychiatric condition(s) or circumstance. Psychotherapy, as well as medication, when appropriate (e.g., proton pump Pump ACES and RUSH: Resuscitation Ultrasound Protocols inhibitors).