Associated descriptive features and mental disorders. When seriously underweight, many individuals with Anorexia Nervosa manifest depressive symptoms such as depressed mood, social withdrawal, irritability, insomnia, and diminished interest in sex. Such individuals may have symptomatic presentations that meet criteria for Major Depressive Disorder. Because these features are also observed in individuals without Anorexia Nervosa who are undergoing starvation, many of the depressive features may be secondary to the physiological sequelae of semistarvation. Symptoms of mood disturbance must therefore be reassessed after partial or complete weight restoration.
Obsessive-compulsive features, both related and unrelated to food, are often prominent. Most individuals with Anorexia Nervosa are preoccupied with thoughts of food. Some collect recipes or hoard food. Observations of behaviors associated with other forms of starvation suggest that obsessions and compulsions related to food may be caused or exacerbated by undernutrition. When individuals with Anorexia Nervosa exhibit obsessions and compulsions that are not related to food, body shape, or weight, an additional diagnosis of Obsessive-Compulsive Disorder may be warranted.
Other features sometimes associated with Anorexia Nervosa include concerns about eating in public, feelings of ineffectiveness, a strong need to control one’s environment, inflexible thinking, limited social spontaneity, perfectionism, and overly restrained initiative and emotional expression. A substantial portion of individuals with Anorexia Nervosa have a personality disturbance that meets criteria for at least one Personality Disorder. Compared with individuals with Anorexia Nervosa, Restricting Type, those with the Binge-Eating/Purging Type are more likely to have other impulse-control problems, to abuse alcohol or other drugs, to exhibit more mood lability, to be sexually active, to have a greater frequency of suicide attempts in their history, and to have a personality disturbance that meets criteria for Borderline Personality Disorder.
Associated laboratory findings. Although some individuals with Anorexia Nervosa exhibit no laboratory abnormalities, the semistarvation characteristic of this disorder can affect most major organ systems and produce a variety of disturbances. The induced vomiting and abuse of laxatives, diuretics, and enemas can also cause a number of disturbances leading to abnormal laboratory findings.
Hematology: Leukopenia and mild anemia are common; thrombocytopenia occurs rarely.
Chemistry: Dehydration may be reflected by an elevated blood urea nitrogen (BUN). Hypercholesterolemia is common. Liver function tests may be elevated. Hypomagnesemia, hypozincemia, hypophosphatemia, and hyperamylasemia are occasionally found. Induced vomiting may lead to metabolic alkalosis (elevated serum bicarbonate), hypochloremia, and hypokalemia, and laxative abuse may cause a metabolic acidosis. Serum thyroxine (T4) levels are usually in the low-normal range; triiodothyronine (T3) levels are decreased. Hyperadrenocorticism and abnormal responsiveness to a variety of neuroendocrine challenges are common.
In females, low serum estrogen levels are present, whereas males have low levels of serum testosterone. There is a regression of the hypothalamic-pituitary-gonadal axis in both sexes in that the 24-hour pattern of secretion of luteinizing hormone (LH) resembles that normally seen in prepubertal or pubertal individuals.
Electrocardiography: Sinus bradycardia and, rarely, arrhythmias are observed.
Electroencephalography: Diffuse abnormalities, reflecting a metabolic encephalopathy, may result from significant fluid and electrolyte disturbances.
Brain imaging: An increase in the ventricular-brain ratio secondary to starvation is often seen.
Resting energy expenditure: This is often significantly reduced.
Associated physical examination findings and general medical conditions. Many of the physical signs and symptoms of Anorexia Nervosa are attributable to starvation. In addition to amenorrhea, there may be complaints of constipation, abdominal pain, cold intolerance, lethargy, and excess energy. The most obvious finding on physical examination is emaciation. There may also be significant hypotension, hypothermia, and dryness of skin. Some individuals develop lanugo, a fine downy body hair, on their trunks. Most individuals with Anorexia Nervosa exhibit bradycardia. Some develop peripheral edema, especially during weight restoration or on cessation of laxative and diuretic abuse. Rarely, petechiae, usually on the extremities, may indicate a bleeding diathesis. Some individuals evidence a yellowing of the skin associated with hypercarotenemia. Hypertrophy of the salivary glands, particularly the parotid glands, may be present. Individuals who induce vomiting may have dental enamel erosion and some may have scars or calluses on the dorsum of the hand from contact with the teeth when using the hand to induce vomiting.
The semistarvation of Anorexia Nervosa, and the purging behaviors sometimes associated with it, can result in significant associated general medical conditions. These include the development of normochromic normocytic anemia, impaired renal function (associated with chronic dehydration and hypokalemia), cardiovascular problems (severe hypotension, arrhythmias), dental problems, and osteoporosis (resulting from low calcium intake and absorption, reduced estrogen secretion, and increased cortisol secretion).