Adolescent Anorexia Nervosa
What is anorexia nervosa?Anorexia nervosa (AN), a form of self-starvation, is an eating disorder characterized by low body weight (less than 85 percent of normal weight for height and age), a distorted body image, amenorrhea (absence of at least three consecutive menstrual cycles when otherwise expected to occur in women), and an intense fear of gaining weight. Anorexia nervosa is sometimes referred to as anorexia.
What causes anorexia nervosa?The cause of anorexia nervosa is not known but is thought to be a complex interplay of genetic, biologic, psychologic and sociocultural factors. A family history of an eating disorder does predispose an individual to an eating disorder but there is increasing interest in the possible role of neurotransmitter abnormalities in the development of anorexia nervosa.
Other mental health problems such as anxiety disorders or affective disorders are commonly found in teens with anorexia.
Who is affected by anorexia nervosa?The occurrence of anorexia nervosa has increased over the past 20 years among adolescents. It is estimated to occur in one out of every 100 females between the ages of 16 and 18 years old. Five to 10 percent of teens diagnosed with anorexia are males. Initially identified in upper- and middle-class families, anorexia is now known to be found in all socioeconomic groups and a variety of ethnic and racial groups.
What are the different types of anorexia?There are two subgroups of anorexic behavior aimed at reducing caloric intake, including the following:
- restrictor type - severely limits the intake of food, especially carbohydrates and fat containing foods.
- bulimia (also called binge-eating/purging type) - eats in binges and then induces vomiting and/or takes large amounts of laxatives or other cathartics (medications, through their chemical effects, that serve to increase the clearing of intestinal contents).
What are the symptoms of anorexia nervosa?The following are the most common symptoms of anorexia. However, each adolescent may experience signs differently.
Symptoms may include:
- low body weight (less than 85 percent of normal weight for height and age)
- intense fear of becoming obese, even as individual is losing weight
- distorted view of one's body weight, size, or shape; sees self as too fat, even when very underweight; expresses feeling fat, even when very thin
- refuses to maintain minimum normal body weight
- in females, absence of three menstrual cycles without another cause
- excessive physical activity in order to promote weight loss
- denies feelings of hunger
- preoccupation with food preparation
- bizarre eating behaviors
- dry skin that when pinched and released, stays pinched
- abdominal pain
- intolerance to cold temperatures
- development of lanugo (fine, downy body hair)
- yellowing of the skin
How is anorexia nervosa diagnosed?Parents, teachers, coaches, or instructors may be able to identify the child or adolescent with anorexia, although many persons with the disorder initially keep their illness very private and hidden. However, a child psychiatrist or a qualified mental health professional usually diagnoses anorexia in children and adolescents. A detailed history of the adolescent's behavior from parents and teachers, clinical observations of the adolescent's behavior, and, sometimes, psychological testing contribute to the diagnosis. Parents who note symptoms of anorexia in their child or teen can help by seeking an evaluation and treatment early. Early treatment can often prevent future problems.
Anorexia, and the malnutrition that results, can adversely affect nearly every organ system in the body, increasing the importance of early diagnosis and treatment. Anorexia can be fatal. Consult your adolescent's physician for more information.
Treatment for anorexia nervosa:Specific treatment for anorexia nervosa will be determined by your adolescent's physician based on:
- your adolescent's age, overall health, and medical history
- extent of your adolescent's symptoms
- your adolescent's tolerance for specific medications or therapies
- expectations for the course of the condition
- your opinion or preference
Possible complications of anorexia nervosa:Medical complications that may result from anorexia include, but are not limited to, the following:
- cardiovascular (heart)
While it is difficult to predict which anorexic patients might have life-threatening heart problems that result from their illness, the majority of hospitalized anorexic patients have been found to have low heart rates. Myocardial (heart muscle) damage that can occur as a result of malnutrition or repeated vomiting may be life threatening. Common cardiac complications that may occur include the following
- arrhythmias (a fast, slow, or irregular heartbeat)
- bradycardia (slow heartbeat)
- hypotension (low blood pressure)
- hematological (blood)
An estimated one-third of anorexic patients have mild anemia (low red blood cell count). Leukopenia (low white blood cell count) occurs in up to 50 percent of anorexic patients.
- gastrointestinal (stomach and intestines)
Normal movement in intestinal tract often slows down with very restricted eating and severe weight loss. Gaining weight helps to restore normal intestinal motility.
- renal (kidney)
Dehydration may be associated with anorexia and results in highly concentrated urine. Polyuria (increased production of urine) may also develop in anorexic patients when the kidneys' ability to concentrate urine decreases. Renal changes usually return to normal with the restoration of normal weight.
- endocrine (hormones)
In females, amenorrhea (cessation of the menstrual cycle for at least three consecutive months when otherwise expected) is one of the hallmark symptoms of anorexia. Amenorrhea often precedes severe weight loss and continues after normal weight is restored. Reduced levels of growth hormones are sometimes found on anorexic patients and may explain growth retardation sometimes seen in anorexic patients. Normal nutrition usually restores normal growth.
- skeletal (bones)
Persons with anorexia are at an increased risk for skeletal fractures (broken bones).When the onset of anorexic symptoms occurs before peak bone formation has been attained (usually mid to late teens), a greater risk of osteopenia (decreased bone tissue) or osteoporosis (bone loss) exists. Bone density is often found to be low in females with anorexia, and low calcium intake and absorption is common.
Prevention of anorexia nervosa:Preventive measures to reduce the incidence of anorexia are not known at this time. However, early detection and intervention can reduce the severity of symptoms, enhance the adolescent's normal growth and development, and improve the quality of life experienced by children or adolescents with anorexia nervosa. Encouraging healthy eating habits and realistic attitudes toward weight and diet may also be helpful.
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