Anorexia Nervosa in Adolescent Patients
How common is anorexia nervosa in adolescent patients? Is screening possible for such patients?
@shripad Eating disorders are among the most prevalent, disabling, and potentially fatal psychiatric illnesses, and the COVID-19 pandemic has exacerbated their burden, with a 15.3% increase in incidence in 2020 compared with previous years. This increase was almost solely among adolescent girls with anorexia nervosa (AN), which is often insidious in onset and more difficult to treat as it advances.
Adolescents with AN are most likely to present to their pediatricians, so awareness and early recognition of the symptoms is critical. Pediatricians are also an integral part of the treatment team in AN and can offer monitoring for serious complications, alongside valuable guidance to parents, who are central to treatment and the reestablishment of healthy eating habits in their children. Here we will review the epidemiology, diagnosis, and treatment of anorexia, with an emphasis on what pediatricians need to know to screen and to facilitate treatment.
AN is marked by a fear of gaining weight or behaviors that interfere with weight gain and a self-evaluation unduly influenced by weight and body shape. Youth with AN often deny the seriousness of their malnutrition, although that is not required for diagnosis. AN can be of a restrictive or binge-purge subtype, and amenorrhea is no longer a requirement for diagnosis.
There is not a specific weight or body mass index cutoff for the diagnosis, but the severity of AN is determined by the BMI percentile normed to age and sex. The average age of onset is 18, and the pre-pandemic prevalence of AN was about 1% of the population. It affects about 10 times as many females as males. It is quite rare prior to puberty, affecting about 0.01% of that age group. There is a heritable component, with a fivefold relative risk in youth with a parent with AN, and twin studies suggest heritability rates as high as 75%.
Youth with rigid cognitive styles appear more vulnerable, as do those who participate in activities such as ballet, gymnastics, modeling, and wrestling because of the role of appearance and weight in performance. More than half of patients with AN will have another psychiatric illness, most commonly anxiety disorders, depression, or obsessive-compulsive disorder. AN becomes chronic in up to 15% of sufferers and the mortality rate is close to 10%, with approximately half dying from medical complications and half dying by suicide.
Parents and pediatricians are usually the first to notice that a child has started to lose weight or is falling off the growth curve. But weight changes usually emerge after feelings of preoccupation with weight, body shape, and body satisfaction. If parents report escalating pickiness around food, increased or compulsive exercise, persistent self-consciousness and self-criticism around weight and body shape, it is worth starting with screening questions.