Approach to feeding and eating disorders: Clinical sciences

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Introduction 0:00–0:28

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.

Unstable Patient 0:28–3:26

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.

Stable Patient 3:26–4:37

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.

Binge-eating Disorder 4:37–5:53

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.
Okay, let’s move on to bulimia nervosa. History typically reveals both binge episodes and inappropriate compensatory behaviors, primarily self-induced vomiting.

Bulimia Nervosa 5:53–7:27

Physical exam usually reveals evidence of compensatory behaviors, like calluses on the knuckles, known as Russell sign, palatal scratches, dental erosion, or parotid gland enlargement.
Sometimes, the physical exam is unremarkable, especially in the absence of self-induced vomiting, or if the compensatory behaviors are laxative abuse or overexercise.
Keep in mind, BMI is highly variable in patients with bulimia nervosa, so it’s not reliable. However, with these clinical findings, consider bulimia nervosa.
Next assess the DSM 5 Criteria. These criteria include the following symptoms present for 3 months or more: binge-purge cycles that occur at least once a week, and patient’s reported self-esteem highly related to their body image.
If both criteria are present, diagnose bulimia nervosa. In terms of treatment, cognitive behavioral therapy is the preferred psychotherapy.
Sometimes, antidepressants, specifically selective serotonin reuptake inhibitors such as fluoxetine, are used as well. Here’s a high-yield fact!
The antidepressant bupropion should always be avoided in patients with bulimia nervosa, since both bulimia and bupropion can increase the risk of seizures.
Time to move on to anorexia nervosa. The patient might report restricted food intake causing significantly low weight and fear of gaining weight.

Anorexia Nervosa 7:27–10:53

On exam, you might find signs of malnutrition, like a BMI of 18.5 or less, temporal wasting, and lanugo, which is the presence of soft, downy hair on the trunk and forearms.
Lanugo develops as an adaptive response to low body fat as a way to regulate body temperature. In this case, consider anorexia nervosa.
To confirm, assess for the DSM-5 criteria. First, the patient must have restricted food intake to the point that it has caused significant weight loss.
Second, the patient must either report an intense fear of weight gain or act in a way that suggests they are intensely afraid of gaining weight.
Finally, a patient must have one of the following: lack of concern about low weight, very poor self-esteem related to their body image, or body image distortion, which is when a patient describes their own body as very different than it objectively appears.
For instance, a patient may describe their stomach as protruding when it is clearly very flat. If all criteria are met, that’s anorexia nervosa.
Here’s a high-yield fact! If a patient has met the three major criteria of anorexia but does not have an underweight BMI, they would be diagnosed with “atypical anorexia.” For instance, this would be the diagnosis for a patient who lost a large amount of weight due to severely restricting food intake, but started at an obese weight, so BMI on exam is in the normal range.
Once you’ve made the diagnosis of anorexia nervosa, the next step is to identify the type. If your patient meets the criteria for anorexia, but there are no binge or purge episodes, diagnose anorexia nervosa, restrictive type.
On the other hand, if they report binge or purge episodes, diagnose anorexia nervosa, binge-purge type. The treatment for stable anorexia nervosa is psychotherapy.
Individual, group, and family-based therapies are frequently utilized. There are no FDA-approved medications for anorexia nervosa.
Here’s a clinical pearl! Although there are some similarities between anorexia nervosa, binge-purge type, and bulimia nervosa, there are 2 key differences between the two.
First, anorexic patients always have some restricting behaviors in addition to compensatory behaviors, and second, the BMI in anorexia patients must be less than 18.5.
Let’s follow it up with a quick clinical pearl on feeding disorders! Feeding disorders include pica, which is when a person consistently eats non-food items such as soil or crayons; and avoidant restrictive food intake disorder, which is a sensory-based food avoidance also known as ARFID.
In both cases, abnormal behaviors must be significant enough to cause impairment in functioning to diagnose the condition.
Feeding disorders can be more common in patients with intellectual disabilities or neurodevelopmental disorders. Undiagnosed feeding disorders can lead to medical complications, such as intestinal blockage or poisoning with pica, or malnutrition and failure to thrive in ARFID.
Alright, as a quick recap… Feeding and eating disorders are conditions that affect food consumption or absorption. If the patient is unstable, consider severe malnutrition.

Review 10:53–11:36

When it comes to stable patients, if history reveals binge episodes and no compensatory behaviors, that’s binge-eating disorder.
However, if you find binge episodes, compensatory behaviors, and a negative body image, think bulimia nervosa. Restrictive food intake to the point of significant weight loss, accompanied by an intense fear of gaining weight, distorted body image, and underweight BMI is characteristic of anorexia nervosa.
Lastly, feeding disorders are less common and include