To say, as adult physicians do, that lifetime mortality from anorexia nervosa is somewhere around ten percent of patients is important and true. It is also, however, an understatement of another toll taken by this illness, particularly in cases of childhood anorexia. Children, more resilient than adults, and having had less time to have developed co-occurring, complicating conditions (e.g. alcohol abuse), are not as likely to die outright, although they can. The most serious effect most children with anorexia nervosa can expect to experience is generally not shortened mortality. It is, rather, the disease’s calamitous impact on the growing brain.
Immediate effects on learning and a common misdiagnosis
Most of the brain's cells are formed before birth, but many of the connections between the cells, which are essential to normal brain functioning, are made during infancy and early childhood. Anything that adversely affects learning, such as the poor concentration (which routinely accompanies fasting and undereating), impoverishes and trims these crucial connections.
The “inability to focus and concentrate,” which is almost universally reported by our young patients and their observant parents, is a direct result of their eating disorders -- not a separate condition, such as attention deficit disorder. Mistaking the poor concentration of semi-starvation for ADD or ADHD frequently leads to the prescription of stimulant medications which, unfortunately, can cause counter-productive appetite suppression. This highlights the critical importance of accurate diagnosis, which is greatly (though imperfectly) supported by the new DSM-5, and the critical importance of prompt, even aggressive, re-feeding.
Lifelong, life-wide repercussions
The brain’s “ability to learn” is not just about the learning that takes place in school. The limbic system (a central part of the brain known to be affected by anorexia nervosa) controls emotions, attachment and memory: all core features affecting what a child will be like as they grow up. Furthermore, the years between birth and age 12 are the prime time for language development, motor development and emotional development. Anything that hinders normal development during these ages can affect a child’s later empathy, happiness, hopefulness and resiliency.
A child’s frontal lobes are the last to become connected. Major functions of the frontal lobes are judgment, insight and impulse control - behavioral attributes which are critical not only to the child themselves, but to everyone around them. The stunting of physical and cognitive growth caused by anorexia nervosa can affect all of this.
In the past, pediatricians have assumed that only starvation during infancy profoundly affected the brain. However, more recent work on famine shows that malnourishment taking place any time during childhood can affect brain development. Some studies have even challenged the concept that the effects of starvation on the growing brain are entirely reversible with later weight restoration. Early identification, interception and treatment of anorexia nervosa are, therefore, critical to ensuring that brain development stays as on-track as possible.