Eating Disorders in the Pediatric Patient

Obesity is a nutritional problem that involves an increase in body weight and accumulation of excess fat, relative to lean body mass. On the other hand, eating disorders are mental health disorders characterized by abnormal eating patterns that can negatively impact physical and mental health. The two most common types are anorexia nervosa, which is a condition characterized by behaviors to prevent weight gain, like restricting the intake of food; and bulimia nervosa, which involves periods of binge eating followed by weight loss techniques like taking laxatives, diuretics, self-induced vomiting, or over-exercising.

Now, the causes of obesity and eating disorders are likely multifactorial, involving genetic, neurochemical, and sociocultural factors. So, a family history of obesity or eating disorders increases the risk of developing these problems.

As far as neurochemical factors go, obesity is associated with alterations in hypothalamic function and regulation of feelings of hunger and satiety, or the feeling of being full after eating. Likewise, eating disorders are thought to be related to changes in brain function that regulate motivation, self-control, and reward, which can impact food intake.

Regarding sociocultural factors, pressure to lose weight, to have a socially defined body type, and partaking in activities that emphasize leanness, like modeling, ballet, gymnastics, and running, can increase the risk for eating disorders. Obesity risk is increased in those who are sedentary and have limited access to healthy food options, most often due to low socioeconomic status or other environmental factors, like communities located in food deserts, or areas with limited access to fresh, quality food.

Now, obesity and eating disorders manifest as changes to the patient’s body mass index, or BMI, which is calculated based on their height and weight.

Generally, pediatric patients who are obese will have a BMI greater than or equal to the 95th percentile for their age and sex. Other findings may include stretch marks on the skin and swollen or painful joints due to pressure from increased weight.

On the other hand, patients with anorexia nervosa usually present with a low BMI due to severe weight loss. Other common findings include a lack of a menstrual period, dry skin, brittle nails, thin hair, and muscle wasting.

Unlike anorexia nervosa, the BMI of patients with bulimia nervosa can be normal or elevated. Additionally, repeated vomiting can lead to erosion of dental enamel and formation of calluses on the knuckles, known as Russell’s sign, which can form when patients use their hand to induce vomiting. Prolonged eating restriction or purging can lead to dehydration and depletion of electrolytes, like potassium, resulting in muscle weakness and even cardiac dysrhythmias.

Alright so, diagnosis of obesity and eating disorders begins with a history and physical examination, including anthropometric measurements like height, weight, and BMI. Secondary causes of weight loss, like type 1 diabetes mellitus, and weight gain, like Cushing syndrome, should also be ruled out.