What is Anorexia?
Anorexia nervosa (AN) is an eating disorder in which individuals attempt to lose weight through diet control and/or excessive physical activity. These individuals may appear to be extremely thin or even emaciated; however, milder forms are often undiagnosed by health care professionals. AN is defined as refusal to maintain body weight at or above 85% of expected body weight. It often starts in the teenage years although it may begin at any age. AN is becoming more prevalent in both men and women. It is also associated with certain sports and activities and may be seen, for example, in wrestlers, runners, dancers, and gymnasts. While AN is typically considered as a preoccupation with weight, it is also related to issues such as self-control. Individuals who have AN are often high-achievers. They may have problems with anxiety or depression.
The nutritional and caloric deficiencies caused by AN lead to medical complications affecting several body systems. Some of these complications may have permanent effects particularly in individuals who develop AN as teenagers since adolescence is a critical period of growth and development. AN can cause electrolyte abnormalities such as low potassium levels. Individuals with AN often have changes in cardiac muscle and function. Many patients develop dangerously low heart rates and other abnormalities associated with an increased risk of sudden death. The heart may have decreased muscle mass and ability to contract, resulting in lower cardiac output. AN is also associated with alterations in the brain resulting in decreased blood flow. AN affects the endocrine system and the secretion of several hormones. Females with AN have decreased levels of estrogen causing loss of menstrual cycles. Individuals with AN also have higher levels of cortisol, which is a stress hormone.
While many of these complications of AN may be reversible, studies show that AN may have permanent effects. Bone health, in particular, is threatened by AN. Osteopenia (bone loss) may occur in anorexia patients as early as the adolescent years and affects multiple bone sites including the spine, hip and wrist. Low bone density increases the risk for bone fractures.
Appropriate treatment for AN requires a multi-disciplinary approach including the primary care physician, psychiatrist/psychologist, nutritionist, and social worker. AN is a chronic condition that must be monitored over the course of several years as relapses are common. Treatment aims for gradual weight gain and maintenance of a healthy weight. Maintaining a healthy weight can help to reverse many of the complications and physiologic changes.
However, osteopenia and osteoporosis may persist despite weight recovery. Individuals with AN should have a bone density evaluation performed by dual energy x-ray absorptiometry (DEXA) scan to assess their risk for osteoporosis. In addition to ensuring sufficient caloric intake, supplementation should include calcium and vitamin D to maximize bone formation. Physical activity is an important part of a healthy lifestyle, but it should be carefully monitored in individuals with AN. Care should be taken to avoid high impact activities that increase the risk for fractures. Excessive exercise is also dangerous. In severely malnourished individuals, any organized exercise is most likely too much.