Anorexia nervosa and bulimia nervosa

Introduction to anorexia nervosa and bulimia nervosa Anorexia nervosa (AN) and bulimiervosa (BN) are common syndromes characterized by a eccentric 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 indicate that the causes of the two diseases are the same, they are all fearful of obesity, so these patients use this food as their life. focus. basic knowledge The proportion of illness: 0.002% Susceptible people: no special people Mode of infection: non-infectious Complications: constipation

Anorexia nervosa and the cause of bulimia nervosa

(1) Causes of the disease

For more than 300 years, endocrine and psychiatrists have analyzed that the disease is the result of a combination of genetic, family, and sociocultural backgrounds.

1. The influence of social and cultural background In the middle of the 20th century, many scholars began to notice that the popularity of AN is mostly young women, more common in developed countries and middle and upper classes, more common in certain special industries (such as ballerinas, models), epidemics The characteristics of learning suggest that social and cultural factors may play an important role. Due to the development of society, people's aesthetics change, adolescent girls are active in thinking, pursuing slimness, and in a male-dominated society, women are easy to adopt male aesthetics. The concept of restraining oneself, so dieting began to prevail in women, the incidence of AN is also increasing year by year.

2. Mental and psychological factors Epidemiology found that more than 80% of AN patients develop symptoms within 7 years of menstrual cramps, and various changes occur in adolescent physiology (such as menstrual cramps, breast bulging, hip circumference, etc.), if 1 Adolescents can't adapt to this change. If they are over-stressed, they may have AN. These patients are mostly unsociable, introverted, self-motivated, or traumatic (such as loss of love, decreased academic performance, etc.) can cause loss of feeling, can be a predisposing factor, patients Obstacles to self-image evaluation, distortion, it is proposed that AN, BN is atypical psychosis, in the family of AN, BN, the incidence of affective diseases is high, the incidence is similar to that of the primary psychiatric family, AN, BN patients Depression is widespread. This symptom is not explained by malnutrition caused by eating disorders, so the emotional disorder is likely to be primary or even the cause.

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

(two) pathogenesis

AN was first described by Marton in 1689. AN has been an interesting topic for endocrinologists and psychiatrists for more than 300 years. However, the etiology and pathogenesis of AN are still not very clear. Most authors believe that this is hereditary. The result of a multifaceted interaction between the family and the socio-cultural background.

The feeding behavior of humans is controlled by the hypothalamic feeding center and the diet center. Although the hypothalamic dysfunction is AN, the etiology of BN is still difficult to be sure, but the clinical evidence indicates that it is related to the dysfunction of the hypothalamus.

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

2. Anti-diuretic hormone secretion is unstable.

3. Pituitary stimulation test suggests that the pituitary hormone reserve function is normal, but the response is delayed.

Anorexia nervosa and prevention of bulimia nervosa

The physiological abnormalities of AN and BN are caused by mental disorders, so proper education should be carried out during adolescence to avoid mental behavior and psychological factors.

Anorexia nervosa and complications of bulimia nervosa Complications constipation

Psychosis and mental abnormality lose self-esteem and self-weight, often accompanied by nausea, vomiting, intractable constipation, a small number of people with episodes of bulimia, normal or lean body weight, giving psychoactive psychotherapy and medication.

Anorexia nervosa and bulimia nervosa symptoms Common symptoms Overeating, picky mouth, gluttony behavior, weight loss, severe cases are "... cachexia, emotional anorexia, obsessive-compulsive concept

Anorexia nervosa

(1) Psychosis and mental abnormalities:

1AN patients often deny that they are sick and refuse treatment. This performance is puzzling.

2 Self-physical image judgment obstacles, so that serious mistakes are judged. Although the body shape is very thin, I still feel that my body shape continues to gain weight.

3 Characters are lonely, depressed, do not trust others, are difficult to interact with people, have low mood, and often have suicidal tendencies.

4 energy is not commensurate with the degree of weight loss, although still extremely thin can still adhere to daily work.

(2) Anorexia: The daily intake is 150g. In severe cases, only a small amount of vegetables or vegetable soup is used. The AN patient loses appetite, has no hunger, refuses, ignores hunger, and strictly controls his food during the whole course. Ingestion, in order to limit the intake of calories as much as possible, in fact, AN patients control the diet from time to time, has occurred 1 year before the onset of the disease.

(3) weight loss: within a few months after the onset of weight loss, more than 15% of the standard weight, AN patients also participate in overweight exercise, more conducive to weight loss, some patients can develop cachexia, if combined with seizures Eaters, weight can be normal or too fat.

(4) Gastrointestinal symptoms: Patients with AN often complain of abdominal pain, bloating, early satiety, slowing of gastrointestinal emptying leading to constipation, and diarrhea caused by laxatives. A small number of AN patients with paroxysmal budding can also cause gastric dilatation or The stomach ruptures, or regrets after eating and induces vomiting.

(5) Malnutrition and low metabolism: dry skin, increased mane, deep skin wrinkles, cold water test on AN patients, blood vessels are abnormally sensitive to hypothermia, showing Raynaud's phenomenon, CT detection found that subcutaneous fat loss is greater than Deep fat loss, therefore, AN is afraid of cold, body temperature can be reduced to 36 ° C, basal metabolic rate is significantly lower than before the disease, slow breathing, hypotension, left ventricular discharge, mitral regurgitation, due to serious Malnutrition, often edema of the extremities, muscle weakness in half of patients, and involvement of peripheral neuropathy have also been reported.

(6) Amenorrhea and secondary sexual deterioration: almost 100% of patients with AN develop amenorrhea, most patients with amenorrhea occur after anorexia and weight loss, but a few occur before anorexia, sexual dysfunction, pubic hair, hair loss, breast, uterus Atrophy, vaginal smear estrogen is moderate or low.

(7) may be associated with hypoglycemia, polyuria: significantly reduced resistance, often accompanied by infection.

2. Neurogenic bulimia

(1) Bulimia: The term BN contains extreme hunger, greedy appetite, and the inability to impact on polyphagous behavior. It usually occurs in women of AN and consumes a lot of food in a short time. After eating, you can vomit in a variety of ways, vomiting a syndrome of a large amount of stomach contents, BN patients should continue to eat to meet the hunger, eat 1 time an average of 1 ~ 2h, each time can get 4810kJ of heat ( 1150kCal), the food is digested in large quantities every day, and the calorie intake can reach up to 20,920kJ (5000kCal). In the course of the disease, the average daily calorie is 14230kJ (3400kCal). The main foods are ice cream, bread, potato chips, cakes, nuts and soft drinks. Usually 1 meal, 1 food, often one person to eat outside at night, usually overeating high-calorie foods, BN people often use toothbrushes, fingers and other things after gluttony, some BN use vomit, vomit can Causes myopathy and cardiovascular disease, these patients fear obesity, will induce vomiting as a way to control weight, until they are spit out to be satisfied, in some BN patients may have stolen behavior, while AN patients do not occur This behavior, other ways of controlling weight, such as excessive exercise, diuretics and laxatives are also common.

(2) phobia: fear of getting fat, fear of obesity, non-gluttony anorexia is caused by fear of fat and exerts amazing perseverance in controlling diet to resist food. On the contrary, BN patients have the ability to lose control of feeding, performance Overeating gluttony appetite; vomiting after vomiting, vomiting and laxatives.

(3) Psychological and mental abnormalities: AN has similar family background to BN, and its incidence is related to family status. Most mothers of BN patients are obese. The driving force of BN patients to eat food is irresistible. The idea of eating is Sustained, even in the dream, it is centered on eating. To satisfy the desire to eat, it is constantly eaten, so that there are stolen behaviors, mental depression, and obsessive attitudes.

(4) Other manifestations: BN patients are not seriously weight-reducing, and some are obese. Some patients have a full moon surface with enlarged parotid glands, scars and dental caries, and BN patients usually do not lose weight. Therefore, amenorrhea is rare. Occasionally, there are few menstrual periods, often accompanied by diarrhea, abdominal distension, abdominal sputum and constipation. Hypokalemia, muscle weakness and paralysis due to frequent and severe vomiting.

Anorexia nervosa and bulimia nervosa

Blood biochemical changes were significant in patients with severe AN, and BN patients were less variable.

1. Anemia, leukopenia and bone marrow have different degrees of inhibition, decreased fibrin levels, hypokalemia and dyslipidemia, and some patients with AN have decreased IgG and IgM.

2. Angiotensin levels increased in plasma and cerebrospinal fluid, plasma zinc and calcium decreased, zinc and calcium were normal, iron binding was decreased, serum iron was normal, serum Amylase was elevated, and BN was more common than AN patients.

3. Endocrine hormone levels and functional tests In AN and BN patients, there is also a hot spot problem: 1 need to confirm the function of the hypothalamic nerve-pituitary axis; 2 in the AN and BN population with amenorrhea need to confirm the presence or absence of each target Primary dysfunction of the gland (Table 1). About half of patients with AN have secondary amenorrhea and episodic polyps. With the rapid decline of body weight, the pituitary gland has an abnormal response to exogenous LHRH. The hypothalamus does not respond to the clomiphene test. When the body weight increases, The above reactions are often reversed to normal, and the pituitary reserve function can be seen with a small amount of LHRH treatment. It is unclear why the hypothalamic manifestation of LHRH is insufficient at AN.

4. ECG examination showed slow heart rate, low voltage, prolonged QT time, non-specific changes in ST segment, U wave and arrhythmia.

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

6. EEG examination Some patients with AN have seizures and present abnormal EEG. EEG abnormalities can return to normal after normal diet. Some people think that the specific amino acids in blood are reduced due to starvation. Necessary neurotransmitters that maintain brain function. In addition, starvation causes trace elements such as zinc, copper, selenium, and magnesium. It affects brain enzymes and hormone function. The symptoms of zinc deficiency are very similar to those of AN, and they are also anorexia. Thickening, depression and other manifestations.

7. Imaging examination of the head CT, MRI examination without hypothalamus, pituitary space-occupying lesions, brain atrophy, ventricle enlargement.

Diagnosis and differentiation of anorexia nervosa and bulimia nervosa

1. The diagnostic criteria of AN

(1) Refusal to maintain a lower limit of the weight of children and adolescents of the same age and normal height, and the weight is lower than 85% of the expected weight.

(2) Despite the low body weight, I still fear that weight gain will become fat.

(3) The self-images are evaluated as obstacles, so that serious mistakes are judged (although they are too skinny, they are still considered too fat).

(4) secondary amenorrhea, that is, three months without menstruation.

Some people in China think that women aged 25 years; anorexia, daily intake <150g and weight loss below 80% of standard weight; with severe malnutrition, without medical and psychiatric patients, should consider the possibility of AN diagnosis , AN can be divided into constrained and bulimia.

2. Diagnosis of BN

(1) Repeated episodes of eating, that is, the intake of food in a fixed period of time is far more than that of the average person in the same period of time; the type of eating and the amount of food intake cannot be controlled during the episode; nor can they control their own diet.

(2) Repeated use of improper methods to prevent weight gain (such as vomiting, laxatives, diuretics, enema, diet pills and intentional fasting or excessive exercise).

(3) At least 2 episodes of bulimia and improper removal of stomach contents per week for more than 3 months.

(4) Obstacles to self-image evaluation.

(5) In the episode of AN, there is no BN performance.

BN is divided into clear type and non-clear type. The former uses various methods to remove stomach contents; the latter uses hunger or excessive exercise to eliminate the consequences of polyphagia. If the weight falls below 85% of the expected body weight, it should belong to AN. Bulimia clearing type.

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