Anorexia Nervosa Part 2


The prognosis of anorexia nervosa is guarded. Morbidity rates range from 10-20%, with only 50% of patients making a complete recovery. Of the remaining 50%, 20% remain emaciated and 25% remain thin.

The remaining 10% become overweight or die of starvation. However, mortality from the complications of starvation is less frequent in patients with anorexia nervosa than is death from suicide. A history of previous suicide attempts, physical pain, drug use, and laxative use may correlate with a higher likelihood of suicide attempts.Metacognition plays a role in predicting adverse outcomes or suicide, as does alexithymia.

Recovery from anorexia nervosa generally is accompanied by resumption in growth, although there may be residual loss of height that is linear in nature.

Prognostic factors

Onset of anorexia nervosa before adulthood predicts a more favorable outcome, although onset at too young an age, before 11 years, is a poor prognostic factor.

The outcome of anorexia nervosa also depends on the patient’s body mass index (BMI) and his or her weight loss at presentation, as well as the duration of symptoms, duration of inpatient care, and state of family relationships. In addition, patients with the restricting subtype of anorexia nervosa tend to be more refractory to treatment and are at high risk of death.

Body weight and symptom duration

Although the degree of weight loss at the clinically noted onset of the involvement of the patient’s organic systems is not predictive of outcome, lower weight (less than 75% of mean body weight [MBW]) and longer duration (more than 19 months) of symptoms were predictors of poorer outcomes in a review of 267 adolescents from 11 different eating disorder programs.

A shorter duration of involvement of the patient’s organic systems before admission and a short inpatient treatment period have been associated with a favorable outcome in some studies.

Mental health

Using nationally representative, face-to-face interview surveys of 10,123 adolescents in the continental United States, Swanson et al found that the majority of those with an eating disorder met the criteria for at least 1 other lifetime DSM-4 disorder, as follows

  • Anorexia nervosa (55.2%)
  • Bulimia nervosa (88%)
  • Binge-eating disorder (83.5%)
  • Subthreshold anorexia nervosa (69.8%)
  • Subthreshold binge-eating disorder (70.1 %)

Psychiatric and somatic comorbidities have been found to worsen the outcome of patients with eating disorders. Psychiatric comorbidities are common with anorexia nervosa, with the following lifetime incidences:

  • Depression (15-60%)
  • Anxiety disorders (20-60%)
  • Substance abuse (12-21%)
  • Personality disorders (20-80%)

Obsessionality and impulsivity in individuals with anorexia nervosa correlate with a lower lifetime BMI, reflecting poorer long-term outcomes, and can be measured with the Yale-Brown-Cornell Eating Disorder Scale (YBC-EDS).

Family involvement

A good relationship between the parent and child tends toward a more favorable outcome. There may be a poorer prognosis among patients from single-parent families, from families in which parents have been married before, and from families in which several generations live together, possibly owing to greater expression of negative emotions in the household. Indeed, joint family therapy is not as effective as separated family therapy if there is a high level of negative emotional expressivity (eg, high levels of maternal criticism).[4]


A meta-analysis by Arcelus et al found a weighted annual mortality incidence for anorexia nervosa of 5.1 deaths per 1000 person-years; a lower mortality rate—1.74 deaths per 1000 person-years—was noted in individuals with bulimia nervosa. However, it is possible that because this study was a meta-analysis, individuals with crossover between anorexia and bulimia could not be correctly tracked, causing loss of data in this study.

Patients who misused alcohol, had a low BMI at presentation, or were of older age at first presentation were found to have a higher likelihood of poor outcomes, including death. Comorbid disorders, such as affective disorder or suicidal behavior or self-harm, or a history of mental-health hospitalization for these problems, also strongly predicted patient mortality.


The presence of an eating disorder has been associated with increased levels of suicidal thinking. Using nationally representative, face-to-face interview surveys of 10,123 adolescents in the continental United States, Swanson et al found the incidence of suicidal ideation and behavior in anorexia nervosa to be as follows:

  • Suicidal ideation: Anorexia nervosa (31.4%); subacute anorexia nervosa (30%)
  • Suicide planning: Anorexia nervosa (2.3%); subacute anorexia nervosa (14.2%)
  • Suicide attempts: Anorexia nervosa (8.2%); subacute anorexia nervosa (12.4%)

According to the meta-analysis by Arcelus et al, 1 in 5 individuals with anorexia nervosa who died had committed suicide.


Most complications of anorexia nervosa are secondary effects from starvation. Malnutrition subsequent to self-starvation leads to protein deficiency and disruption of multiple organ systems, including the cardiovascular, renal, gastrointestinal, neurologic, endocrine, integumentary, hematologic, and reproductive systems. Endocrine and metabolic disturbances, for example, result in the following

  • Delayed puberty
  • Amenorrhea
  • Anovulation
  • Low estrogen states
  • Increased growth hormone
  • Decreased antidiuretic hormone
  • Hypercarotenemia
  • Hypothermia
  • Hypokalemia
  • Hyponatremia
  • Hypoglycemia
  • Euthyroid sick syndrome
  • Hypercortisolism
  • Arrested growth
  • Osteoporosis

In addition, decreased gonadotropin levels and hypogonadism may occur among males who are affected.

Cardiovascular effects of anorexia nervosa include the following:

  • Cardiomyopathy
  • Mitral valve prolapse
  • Supraventricular and ventricular dysrhythmias
  • Long QT syndrome
  • Bradycardia
  • Orthostatic hypotension
  • Shock due to congestive heart failure

Renal disturbances include the following:

  • Decreased glomerular filtration rate (GFR)
  • Elevated BUN
  • Edema
  • Acidosis with dehydration
  • Hypokalemia
  • Hypochloremic alkalosis with vomiting
  • Hyperaldosteronism
  • Renal calculi

Gastrointestinal findings in anorexia nervosa include the following:

  • Constipation
  • Decreased intestinal mobility
  • Delayed gastric emptying
  • Gastric dilation and rupture: From binge eating and purging; gastric rupture can lead to pneumothorax and pneumoperitoneum

Neurologic disturbances include the following:

  • Peripheral neuropathy
  • Ventricular enlargement

Integumentary findings include the following:

  • Dry skin and hair
  • Hair loss
  • Lanugo body hair

Hematologic findings include the following:

  • Anemia
  • Leukopenia
  • Thrombocytopenia

Reproductive disturbances include the following:

  • Infertility
  • Low ̶ birth-weight infant

Patients who induce vomiting develop dental enamel erosion, palatal trauma, enlarged parotids, esophagitis, Mallory-Weiss lesions, elevated transaminase levels, and, in extreme cases, seizures (due to electrolyte disturbances). Cases of superior mesenteric artery (SMA) syndrome from loss of intraperitoneal fat in anorexia nervosa have been reported.


In the Swanson study, 97.1% of adolescents with anorexia nervosa reporting suffering from some form of impairment (most commonly, social impairment) in the previous 12 months, with 24.2% reporting severe impairment; 11.6% reported a complete inability to carry out normal activities for at least 1 day.

Patient Education

According to Becker et al, for adequate weight gain, the patient or family requires some “education on nutrition, adjustment of caloric and nutritional intake, and limitations on exercise and other modifications of behavior,” with enteral or parenteral nutrition being used only in patients with severe undernutrition who have not responded to these other methods.

In the moderate stage of anorexia nervosa, in addition to the above recommendations, providing structure to daily activities is necessary. This includes eating 3 meals a day. Also, parents should ensure that healthy food is available, but the patient should assume all responsibility for eating.

For patient education information, see the Women’s Health Center, as well as Anorexia Nervosa, Bulimia, and Amenorrhea. Other useful sources of patient information include the following:


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