Definition and Diagnosis
Anorexia nervosa is an eating disorder characterized by persistent restriction of energy intake relative to requirements, leading to a significantly low body weight, along with an intense fear of gaining weight and a disturbance in the way one's body weight or shape is experienced.
Epidemiology
Anorexia nervosa has a lifetime prevalence of roughly 1-2% in women and a lower but clinically significant rate in men. Onset typically occurs in adolescence or early adulthood, and it carries one of the highest mortality rates of any psychiatric disorder if left untreated.
Risk Factors
Risk factors include a family history of eating disorders or other psychiatric conditions, perfectionistic or anxious personality traits, participation in appearance- or weight-focused activities, and sociocultural pressure around thinness. A history of dieting is also a common precursor.
Symptoms and Subtypes
Core features include restrictive eating leading to low body weight, intense fear of weight gain even when underweight, and a distorted perception of body shape or size. Physical signs can include fatigue, dizziness, cold intolerance, hair thinning, and in females, loss of menstrual periods.
Diagnosis
Diagnosis follows DSM-5-TR criteria, requiring restriction of intake resulting in significantly low weight, fear of weight gain or persistent behavior interfering with weight gain, and disturbance in body image. Medical evaluation typically screens for cardiovascular, electrolyte, and bone health complications given the risks of malnutrition.
Treatment
Treatment is multidisciplinary and often includes medical stabilization, nutritional rehabilitation, and specialized psychotherapy such as family-based treatment for adolescents or CBT for adults. Depending on medical severity, care may range from outpatient support to inpatient or residential programs.
Prognosis
Outcomes improve significantly with early intervention, particularly in adolescents treated with family-based approaches. Without treatment, anorexia nervosa tends to be chronic and carries substantial medical risk, making ongoing monitoring an important part of recovery.
Reference
American Psychiatric Association. (2022). Diagnostic and Statistical Manual of Mental Disorders (5th ed., text rev.).