Approach to feeding and eating disorders: Clinical sciences

Feeding and eating disorders are conditions in which abnormal eating-related habits contribute to poor food consumption or absorption to such a degree that physical or mental health is impaired.

Feeding disorders include conditions such as pica and avoidant restrictive food intake disorder while eating disorders include binge-eating disorder, bulimia nervosa, and anorexia nervosa.

When a patient presents with a chief concern suggesting an eating disorder, first, perform an ABCDE assessment to determine if they are stable or unstable. If unstable, initiate acute management by stabilizing their airway, breathing, and circulation. Also, administer supplemental oxygen if needed, obtain IV access, and consider starting IV fluids. Then, continuously monitor vital signs including respiratory rate, pulse oximetry, and cardiac telemetry.

Your next step is to obtain a focused history and physical exam and order labs, including CBC, CMP, serum magnesium, phosphate, and urinalysis, as well as a 12-lead ECG.

History might reveal greater than 10 percent weight loss in the last 6 months, while the exam might show bradycardia, hypotension, or even hypothermia. Additionally, the body mass index, or BMI, might be less than 15.

On labs, CBC could reveal low hemoglobin suggesting anemia. You might also find hypoglycemia, or electrolyte imbalances such as hyponatremia, hypomagnesemia, hypophosphatemia.

In some cases there might be an acid-base disorder. For example, excessive vomiting can lead to metabolic alkalosis while laxative abuse causing excessive diarrhea can result in metabolic acidosis.

Additionally, urinalysis might reveal the presence of ketones. Finally, ECG findings can include QTc prolongation, arrhythmias, and other changes related to electrolyte disturbance.

These findings should make you think of severe malnutrition from a feeding or eating disorder, most commonly anorexia nervosa or bulimia nervosa.
When it comes to management, patients with severe malnutrition require hospitalization. Restart and increase their oral intake.

Be sure to monitor for refeeding syndrome, which refers to abnormalities in electrolyte and fluid balance when a malnourished patient increases food consumption. Hypophosphatemia is the hallmark feature of refeeding syndrome as the increased production of ATP from the food consumed depletes the body’s phosphate stores.

Other complications include arrhythmias, congestive heart failure, kidney failure, and rhabdomyolysis. The best way to prevent this is slow refeeding. Also, monitor and replace electrolytes such as potassium, calcium, magnesium, and phosphate. Daily fluid intake and output should be recorded to ensure proper rehydration.

Next, include daily examination for the development of peripheral edema, which can occur from the combination of hypoproteinemia, electrolyte imbalance, and hormonal irregularities.

A multidisciplinary team approach, including psychiatric, medical, and nutrition professionals, is needed for the comprehensive care of the patient.

Now that the unstable patients are taken care of, let’s go back and talk about stable ones. Your first step here is to obtain a focused history and physical exam and calculate the patient’s BMI. History typically reveals low or high daily food intake, recent weight loss or gain, or abnormal behaviors around eating food. They might also report excessive preoccupation with eating, weight, or body shape.

On exam, BMI can be high, normal, or low for their age group. With these findings, you should consider eating disorders.

Here is a clinical pearl! When evaluating for a suspected eating disorder, it is important to evaluate for the presence of binge episodes and compensatory behaviors.

Binge episodes are when a person eats an objectively large amount of food in a discrete period of time, while feeling a lack of control over their eating.

Compensatory behaviors, if present, typically occur after a binge episode. These behaviors are aimed at preventing food absorption and may include self-induced vomiting, excessive use of laxatives or diuretics, or engaging in exhaustive exercise.

Let’s first discuss binge-eating disorder. Patients typically have a history of binge episodes but no compensatory behaviors.

The physical exam might show a BMI greater than 30. These findings should lead you to consider binge-eating disorder.

To confirm, assess the DSM-5 diagnostic criteria. These include 3 or more of the following symptoms present at least once a week for 3 months or more: eating rapidly, eating to the point of feeling uncomfortable, eating when not hungry, eating alone due to embarrassment, or feeling depressed, guilty, or shame after binge episodes. If the criteria are met, diagnose binge-eating disorder.

Here’s another clinical pearl! Patients with binge-eating disorder are at increased risk of obesity and related conditions, such as type 2 diabetes and metabolic syndrome. However, only half of these patients have a BMI greater than 30, so a normal BMI does not rule out this condition. Treatment for binge eating disorder is typically a combination of psychotherapy, usually cognitive behavioral therapy, and medication like lisdexamfetamine.