Guest Author Dr. Caroline Nguyen is primary care physician, adolescent medicine specialist, and an assistant professor at UCSF in the Department of General Internal Medicine.
We return to Natalie, a 32 yo woman with anorexia nervosa-restricting type, who restricts her calories to 1000kcal per day and overexercises by running 40+ miles/week. She has lost 30lbs over the last year, with her BMI decreasing from 22 to 18kg/m2. She has not had a period in the last six months. Today, she feels fine. Her BMI is 17.5, temperature is 36.6F, and orthostatic vital signs: sitting HR 49, BP 92/48; standing HR 70, BP 85/40.
Classification of restrictive eating disorders
Restrictive eating disorders are defined by calorie restriction and resulting malnutrition. The most common restrictive eating disorder is anorexia nervosa (AN). People with AN intentionally restrict energy intake and have an intense fear of weight gain, body dysmorphia and/or a lack of recognition of the severity of malnutrition. AN can be restricting type (calorie restriction +/- overexercising (hypergymnasia) only) or binge/purge type (characterized by binges and compensatory purging through emesis, laxatives, or hypergymnasia).
Avoidant restrictive food intake disorder (ARFID) is a rarer restrictive eating disorder. ARFID is characterized by an eating disturbance (e.g. lack of interest in food, sensory aversion, or fear of an aversive consequence of eating, like choking) that causes weight loss and malnutrition. People with ARFID do not intentionally lose weight and there is no body dysmorphia component (Feltner, 2022). However, people with ARFID can develop the same medical complications of malnutrition as people with AN.
Physical exam findings and medical complications of restrictive eating disorders
Patients with restrictive eating disorders often have telltale signs of general malnutrition and/or purging on physical exam.
| Malnutrition | Purging | |
| Physical exam findings | Low body weight (BMI<18.5 kg/m2) Bradycardia (HR < 50) Hypotension (SBP <100, DBP <60) Shorter stature (if pre/pubertal at onset) Temporal wasting Lanugo (fine, soft hair growth on body) Dependent edema Diminished heart or breath sounds due to pericardial or pleural effusions | Poor dentition Parotid gland enlargement Scarring/injury to dorsal side of finger |
| Medical complications | Electrolyte derangement (e.g.hypoK, hypoNa, hypoPhos) Hypoglycemia Amenorrhea and osteoporosis Bradyarrhythmia Anemia Hyperlipidemia (due to increased fat metabolism) Micronutrient deficiency Euthyroid sick syndrome Volume overload (edema, pleural / pericardial effusion) | Electrolyte derangement (e.g. hypoNa, hypoK metabolic alkalosis if emesis, hypoK metabolic acidosis if laxative use) Dental caries Esophagitis Esophageal tear Chronic constipation from laxative use Finger trauma/skin infection |
How do you support a patient with a restrictive eating disorder in primary care?
Regular primary care appointments (ranging from weekly to every 3 months) are important for patients with restrictive eating disorders. The patient’s degree of malnutrition and rate of weight loss dictate the level of risk and influence the frequency of visits.
Ideally, a patient with a restrictive eating disorder should have a team of clinicians, including an outpatient therapist focused on the psychological drivers and impacts of restrictive eating, a dietician focused on meal planning and food intake, and a primary care provider monitoring the severity of malnutrition and managing the medical complications.
In a routine primary care visit, vital signs should be done in a dependable, predictable way to minimize distress and allow for comparison over time. Check the patient’s height and weight at every visit. Consider weighing patients with AN and malnutrition in a gown only, after they empty their bladder, with the patient stepping on the scale backward so that they don’t see the number. The urine specific gravity can be checked to look for water loading that would artificially increase the weight.
Ask the patient about eating, purging, and exercise at each visit. Asking a patient what they have eaten in the last 24 hours can be helpful.
If you’re worried about rapid weight loss or the patient is frequently purging, order basic labs with electrolytes. Female patients who have been amenorrhoeic for more than 6 months should begin annual DEXA screening for osteopenia/osteoporosis.
When does your patient need to be admitted to the hospital for inpatient management of malnutrition?
The purpose of a medical hospitalization is medical stabilization, specifically the resolution of the abnormal vital sign or lab finding that led to their hospitalization. While in the hospital, the patient gradually increases caloric intake and is monitored for refeeding syndrome. Patients with restrictive eating disorders are usually hospitalized in a regular medical hospital, though specialized inpatient eating disorder units are available in some locations.
Criteria for Inpatient Medical Admission:
| Quantitative | Qualitative |
| 75% median BMI or BMI <15 Electrolyte disturbance (e.g. hypoK / hypoNa requiring monitoring and / or repletion) EKG abnormality (long QT or bradycardia <50 awake or <45 during sleep) Hypotension: BP <90/45, Orthostasis (increase in HR 30+, or drop in BP 20mmHg systolic / 10mmHg diastolic) | Failure of outpatient treatment Acute food refusal Uncontrollable purging Any other acute complication of malnutrition (heart failure, pancreatitis) Comorbid psychiatric or medical condition that inhibits outpatient management (severe mood disorder, insulin dependent DM) |
Society for Adolescent Health and Medicine 2022
“Failure of outpatient treatment” has no strict definition and can represent sustained failure to gain weight or severe or rapidly worsening malnutrition, as examples. The criteria are intentionally broad to allow for flexibility in deciding who may benefit from an inpatient admission. Some patients will meet one or more of these criteria, but can be followed closely in the outpatient setting in lieu of admission through shared decision making.
What if my patient needs a higher level of psychiatric care?
Often patients with restrictive eating disorders do not meet criteria for an inpatient medical admission but still need a higher level of psychiatric care for their eating disorder. Patients may need a higher level of psychiatric care than a once weekly outpatient therapy if their distress around eating, weight gain, or body image prevents them from interacting with others or going to school or work.
| Level of Psychiatric Care | Intensity |
| Outpatient | Usually once weekly therapy sessions |
| Intensive Outpatient Program (IOP) | Several hours of treatment 3-5 days/week |
| Partial Hospitalization Program (PHP) | Treatment for 5+ hours per day, 5 days a week |
| Residential Program | Patients live at facility, receive many hours of individual and group therapy and structured/supervised meals |
| Inpatient Psychiatric Hospitalization | For those at imminent risk of harm to self |
There is a VERY wide variety in the hours/frequency/type of therapy at each level of care. Most IOPs, PHPs, and residential eating disorder programs offer no medical care. Patients are often followed medically by their PCP while they are in these programs.
If a patient is in a higher level of psychiatric care, it is best practice to step down sequentially through the levels of care before returning to outpatient therapy. If a patient is admitted to a medical hospital for malnutrition from a restrictive eating disorder, they should ideally be discharged to a residential, PHP, or IOP program for ongoing psychiatric care.
Returning to Natalie:
With a HR of 49 (bradycardia (HR<50) when sitting), BP 85/40 (hypotension (BP <90/45) when standing), and ongoing weight loss over a year (failure of outpatient management), it would be reasonable to recommend an inpatient medical admission. If Natalie can make a concrete plan to increase caloric intake and decrease exercise, she could be seen frequently (once a week or every other week) while linking to a higher level of psychiatric care. Natalie also should get a DEXA scan now due to 6 months of amenorrhea.
Key Points:
- Specific physical exam and lab findings determine the severity of malnutrition or the medical sequelae of purging.
- If a patient is medically unstable due to a restrictive eating disorder, the next level of care is inpatient medical admission.
- Higher levels of psychiatric care for patients with restrictive eating disorders include eating disorder-specific IOPs, PHPs, residential programs, and inpatient psychiatric units.
Related psychsnaps
References
Feltner, C., et al. (2022). Screening for Eating Disorders in Adolescents and Adults: Evidence Report and Systematic Review for the US Preventive Services Task Force. JAMA, 327(11), 1068.
Society for Adolescent Health and Medicine. (2022). Medical Management of Restrictive Eating Disorders in Adolescents and Young Adults. J Adolesc Health. 71(5), 648-654.