What are Causes of Anorexia Nervosa?

Anorexia nervosa

Anorexia nervosa and Bulimia nervosa

Anorexia nervosa (AN) and bulimia nervosa (BN) are common syndromes characterized by a weird eating state. AN and BN are two different clinical manifestations of the same chronic eating disorder. Although the clinical manifestations and outcomes of the two syndromes are different, these characteristics point out that the etiology of the two diseases is the same, and they are both afraid of obesity. As a result, these patients take this feeding as the focus of their lives. The main characteristics of the two diseases of AN and BN are the special psychological abnormalities of some adolescents, with lean body image disorders, and the use of antifeeding, vomiting, and diarrhea to reduce body weight, causing extreme malnutrition and weight loss and amenorrhea even death. Patients with AN strictly control food intake, while patients with BN lose control of eating, so that they are compensated by refusing food and inducing vomiting.

Anorexia nervosa and Bulimia nervosa symptoms and signs

Anorexia nervosa

(1) Psychological abnormalities and mental disorders: AN patients often deny that they are ill and refuse treatment, which is puzzling. Obstacles to self-image judgment, resulting in serious errors in judgment. Although she is very thin, she still feels that she is getting fatter. Withdrawn personality, mental depression, distrust of others, difficulty in communicating with others, low mood, and often suicidal tendency. The energy is not commensurate with the degree of weight loss, and despite the extreme weight loss, I can still persist in my daily work.

(2) Anorexia: daily intake 150g, severe cases only live with a small amount of vegetables or vegetable soup, AN patients show loss of appetite, no hunger, or refuse or ignore hunger throughout the course of the disease; strictly control their food Intake to minimize calorie intake. In fact, patients with AN control their diet from time to time, which has occurred 1 year before the onset of this disease.

(3) Wasting: weight loss within a few months after onset, mostly below 15% of standard weight. AN patients also participate in overweight exercise, which is more conducive to weight loss. Some patients can develop cachexia. If combined with bulimia bulimia, the weight can also be normal or overweight.

(4) Gastrointestinal symptoms: AN patients often complain of abdominal pain, bloating, early satiety, slowing of gastrointestinal emptying, and constipation. There are also diarrhea caused by laxatives. A small number of AN patients with bulimia bulimia can also cause gastric dilation or gastric rupture, or regret and induce vomiting after eating.

(5) Malnutrition and low metabolism: dry skin, increased coats, and deeper skin wrinkles. Cold water test in patients with AN, the blood vessels are abnormally sensitive to hypothermia, showing Raynaud's phenomenon. CT examination found that the loss of subcutaneous fat was greater than the loss of deep fat. Therefore, those who suffer from AN are afraid of cold, and their body temperature can be lowered to 36 ° C. Basal metabolic rate was significantly lower than before disease. Slow breathing and low blood pressure. Left ventricular blood flow was reduced, and mitral regurgitation. Due to severe malnutrition, limb edema often occurs, and muscle weakness occurs in half of the patients. Involvement of peripheral neuropathy has also been reported.

(6) Amenorrhea and second sexual deterioration: Almost 100% of patients with AN have amenorrhea. Most amenorrhea occurs after anorexia and weight loss, but a few occur before anorexia. Sexual dysfunction, shedding of pubic hair and armpit hair, atrophy of breasts and uterus, and low or moderate estrogen in vaginal smear.

(7) May be accompanied by hypoglycemia, polyuria: markedly reduced resistance, often accompanied by infection.

Bulimia nervosa

(1) Gluttony: The term BN contains extreme hunger, greedy appetite, and has an unstoppable power on polyphasic behavior. It usually also occurs in women with AN, a horrible intake of a large amount of food in a short period of time, and after eating it induces vomiting in a variety of ways and vomits a large amount of stomach contents. BN patients continuously eat to satisfy their hunger. On average, they eat once every 1-2 hours, and they can get 4810kJ (1150kCal) each time. Food is digested in large quantities every day, and calories can be as high as 20920kJ (5000kCal). During the course of the disease, an average daily calorie of 14230kJ (3400kCal) was obtained. The main foods are ice cream, bread, potato chips, pastries, nuts and soft drinks. Usually one meal per meal. They often eat outside at night, usually overeating high-calorie foods. BN people often use toothbrushes, fingers, etc. to induce vomiting after overeating. Some people with BN take roots, which can cause myopathy and cardiovascular disease. These patients are afraid of obesity, and use evacuation as a way to control weight. They are not satisfied until they all vomit. In some BN patients, there may be stealing behavior, but AN patients do not. Other ways to control weight, such as excessive exercise, diuretics and laxatives are also common.

(2) Phobia: Fear of getting fat and having fear of obesity. Non-bulimic anorexia nervosa by fear of obesity is manifested in an amazing persistence in controlling the diet, which leads to refusal to eat. In contrast, patients with BN lose control of food intake, show gluttonous appetite and overeating; induce vomiting, vomiting, and laxatives after eating.

(3) Psychological and mental disorders: AN and BN have similar family backgrounds, and their incidence is related to family conditions. The mothers of patients with BN are mostly obese. The driving force of BN patients is irresistible. The idea of eating is persistent, and even eating is centered in dreams. If you want to satisfy the desire to eat, you keep eating, which leads to stealing behavior, mental depression, and obsessions.

(4) Other manifestations: The weight loss of BN patients is not serious, and some are obese. Some patients have full moon faces with enlarged parotid glands, scar physiques and caries. BN patients are usually not wasted. Therefore, amenorrhea is rare, and occasionally menstruation is rare. It is often accompanied by diarrhea, bloating, abdominal belching and constipation. Hypokalemia, muscle weakness and cramps are caused by frequent and severe vomiting.

Anorexia nervosa and Bulimia nervosa medication

There is no specific treatment for the treatment of AN and BN. At present, mainly rely on psycho-behavioral therapy and diet therapy, supplemented by medication.

Mental behavior therapy

(1) Treat patients with sincerity, patience, and seriousness, and fully gain patient trust.

(2) Adjust family relationships and help build good relationships with others.

(3) Do subtle psychological work to correct patients' misunderstanding and stubborn prejudice about weight and eating.

2. Diet therapy Based on good psycho-behavioral therapy, reasonable diet therapy will quickly achieve significant results. Because no medicine is more important than care and diet.

(1) AN: Children follow the normal weight growth curve, and adults use body mass index as a treatment index. The goal of treatment is to gain 225 to 1350 g of body weight per week. At the beginning of treatment, add 2134J (510cal) calories of food daily on the basis of maintaining weight. During the weight gain period, 293 to 418 J (70 to 100 cal) calories are needed per kilogram of body weight per day; during the weight maintenance period, 167 to 251 J (40 to 60 cal) calories are required. Another method is to add 10% to 20% of the calories needed to maintain a standard weight.

Nasal feeding or intravenous nutrition can be used for severe malnutrition and life threatening. Give the patient liquid food to add more heat.

(2) BN: The diet of BN patients should pay attention to changing food types. Should be based on carbohydrates, eat some vegetables and fruits intermittently to extend the eating time, and delay the gastric emptying time with a suitable fat diet. People with BN should eat in a seated position, eat hot food, do not grab food with their fingers, and make a meal record.

3. Drug therapy The drugs used to treat AN mainly target patients with food anxiety, improve the function of gastric emptying, and restore the function of the hypothalamus-pituitary-gonadal axis. Since depression can often improve after weight recovery, one stage should be observed before deciding whether antidepressant medication is needed.

(1) Anti-psychotic depression drug: chlorpromazine: An antipsychotic drug that can block the central dopamine receptor, usually 25 to 100 mg / time, 2 to 3 times / day. At present, it is believed that the psychological abnormality of AN may be the result of enhanced central nervous system dopamine activity, and reduce anxiety about diet after serving.

Imiprimine: a tricyclic antidepressant, 25-35 mg / time, 3 times / d. Depression is quite common in patients with AN. Some patients with AN still have depression after returning to the normal diet. Application of imipramine can prevent AN from remaining in a depressed state after a normal diet.

Lorazepam: a short-acting benzodiazepine, 0.5 to 1 mg / time or 15 mg of oxazepam, a similar drug. This medicine has anti-anxiety and appetite enhancement effects.

(2) Drugs for promoting gastrointestinal exercise: There are two types of commonly used drugs: dopamine receptor blockers, such as metoclopramide; cholinergic agents, such as clobeline. Promote gastric emptying after taking, relieve symptoms such as postprandial fullness and upset stomach.

(3) Zinc preparation (zinc sulfate): Zinc deficiency is similar to the clinical symptoms of AN. After treatment with zinc sulfate 45-90mg / d for 8-16 months, some patients have menstrual cramps and get better results.

(4) Gonadotropin-releasing hormone (LHRH): pump infusion, 12.5mg is injected subcutaneously automatically every 90min. After short-term treatment, appetite improves, weight gain, mental improvement, menstrual cramps.

(5) Sibutramine.

Anorexia nervosa and bulimia nervosa

You should eat celery, golden needles, leek, winter melon, black plum, persimmon, sesame, lotus seeds, sea cucumber.

Anorexia nervosa and bulimia nervosa preventive care

The physiological abnormalities of AN and BN are caused by mental and psychological disorders. Therefore, proper education should be carried out during adolescence. Avoid mental and behavioral causes of illness.

Pathological causes of anorexia nervosa and bulimia nervosa

For more than 300 years, endocrinologists and psychiatrists have determined that the disease is the result of a combination of genetic, family, and socio-cultural backgrounds.

1. The impact of social and cultural background In the middle of the 20th century, many scholars began to notice that the prevalence of AN was mostly young women, more common in developed countries and middle and upper classes, and more common in some special industries (such as ballet dancers, models). Epidemiological characteristics suggest that sociocultural factors may play an important role. Due to the development of society, people's aesthetics have changed. Adolescent girls are active in their thoughts and pursue slenderness. In addition, in a male-dominated society, women can easily restrain themselves with male aesthetics. So dieting became popular among women. The incidence of AN has also increased year by year.

2. Mental and psychological factors Epidemiology found that more than 80% of patients with AN developed symptoms within 7 years of menstrual cramps. Various changes occur during adolescence physiology (such as menstrual cramps, breast bulges, and enlarged hips, etc.). If a young girl cannot adapt to this change, AN may be caused by psychological stress. Most of these patients are lonely, introverted, self-motivated, or the feeling of loss caused by trauma (such as falling in love, declining academic performance, etc.) can be a trigger. Patients have impaired and distorted self-image evaluation. Some people have suggested that AN and BN are atypical mental illnesses. In AN and BN families, the incidence of affective diseases is high. The incidence is similar to that of primary psychiatric families. Depression is common in AN and BN patients. This symptom cannot be explained by malnutrition caused by eating disorders alone. . So affective disorders are likely to be primary or even etiological.

3. Biological factors Genetic factors may have a certain effect on this disease, and it is relatively consistent that the abnormal function of hypothalamus is related to the occurrence of this disease.

Diagnosis of anorexia nervosa and bulimia nervosa

No related information.

Anorexia nervosa and bulimia nervosa

Laboratory inspection:

The blood biochemical changes were obvious in patients with severe AN, and the changes were small in patients with BN.

1. Anemia, leukopenia, and bone marrow suppression to varying degrees. Reduced fibrin levels, hypokalemia and dyslipidemia. Some AN patients have decreased IgG and IgM.

2. Angiotensin levels are elevated in plasma and cerebrospinal fluid. Plasma zinc and calcium decreased, and zinc and calcium in hair were normal. Iron binding decreased, but serum iron was normal. Serum Amylase is elevated, and BN is more common than in patients with AN.

3. Endocrine hormone level and function test In AN and BN patients, there is also a hot issue: it is necessary to confirm the function of the hypothalamic nerve-pituitary axis; in the AN and BN population with amenorrhea, the existence of each target Glandular primary dysfunction (Table 1).

Approximately half of patients with AN are accompanied by secondary amenorrhea and seizures. With the rapid decrease in body weight, the pituitary responds to exogenous LHRH abnormally, and the hypothalamus does not respond to the clomiphene test. When weight gains, these reactions often reverse to normal. Treatment with a small amount of LHRH can see the pituitary's reserve function. It is unclear why the hypothalamus manifests LHRH deficiency during AN.

Other auxiliary checks:

1. ECG examination It can be seen that the heart rate is slow, low voltage, QT time is prolonged, non-specific changes in ST segment, U wave and arrhythmia appear.

2. X-ray examination can find osteoporosis and kidney stones.

3. EEG examination Some patients with AN are associated with seizures and present abnormal EEG. EEG abnormalities can return to normal with a normal diet. It is thought that specific amino acids in the blood are reduced due to starvation, and these amino acids are necessary neurotransmitters to maintain brain function. In addition, hunger causes deficiency of trace elements such as zinc, copper, selenium, and magnesium, which affects enzyme and hormone functions in the brain. The symptoms of zinc deficiency are very similar to the symptoms of AN, but also manifested as anorexia, coarse pronunciation, and depression.

4. Imaging examination CT and MRI of the skull showed no hypothalamic or pituitary space occupying lesions. May have brain atrophy, ventricle enlargement.

Anorexia nervosa and bulimia nervosa complications

Psychological abnormalities and mental disorders lose self-esteem and self-esteem, often accompanied by nausea, vomiting, refractory constipation, and a small number of people with bulimia. Normal or thin. Give psycho-behavioral psychotherapy and medication.

Prognosis of anorexia nervosa and bulimia nervosa

If patients do not receive active treatment, the mortality rate is as high as 5% -20%. The cause of death may be suicide, malnutrition, infection, and cardiac depression. If the treatment is actively received, the prognosis is good. After a certain period of treatment, the patient may get significant nutritional improvement, weight gain, and menstrual cramps. If treatment is complete, the relapse rate is low, but some patients may experience emotional abnormalities.

Anorexia nervosa and Bulimia nervosa

AN was first described by Marton in 1689. AN has been an interesting subject for endocrinologists and psychiatrists for more than 300 years. However, the etiology and pathogenesis of AN remain unclear. Most authors believe that this is the result of a combination of genetic, family, and socio-cultural backgrounds.

Human feeding behavior is controlled by the hypothalamus feeding center and diet center. Although the hypothalamic dysfunction is the cause of AN and BN, it is still difficult to be sure, but clinical evidence shows that it is related to the primary hypothalamic dysfunction.

1. In about 20% of patients, amenorrhea is the first symptom. The occurrence of amenorrhea indicates hypothalamic-pituitary-gonadal axis dysfunction.

2. Unstable secretion of antidiuretic hormone.

3. The pituitary excitability test indicates that the pituitary hormone reserve function is normal, but the response is delayed.