Oct. 20, 2021
Mayo Clinic gastroenterologist Brian E. Lacy, M.D., Ph.D., and co-authors describe several maladaptive eating behaviors and provide useful tools to help clinicians identify and treat these illnesses in a review article published in The American Journal of Gastroenterology in 2021. The article describes the four most common subtypes of eating disorders (EDs), including anorexia nervosa, avoidant/restrictive food intake disorder, bulimia nervosa and binge-eating disorder, and outlines the symptoms, physical examination findings and diagnostic clues associated with each.
Why is the ability to recognize EDs important for gastroenterologists and hepatologists?
EDs are highly prevalent. They affect up to 24% of patients seen in gastroenterology practice, and they can dramatically affect the health and well-being of our patients. Unidentified EDs can interfere with effective management of gastrointestinal (GI) disease and its symptoms. Without treatment, EDs may lead to the development of anxiety, depression and somatization disorders.
EDs are also associated with a variety of medical complications, some of which include the GI tract. Anorexia and bulimia, for example, may lead to parotid gland enlargement, dental caries, regurgitation, delayed gastric emptying, constipation, rectal prolapse and even life-threatening electrolyte disorders.
My co-authors and I want to help gastroenterologists and other clinicians recognize, evaluate and diagnose patients with EDs. We need to look for these disorders and focus on a team approach for treatment.
What are some of the challenges that gastroenterologists encounter when treating patients with these disorders?
EDs frequently coexist with and masquerade as common gastrointestinal disorders. Because they can be a plausible explanation for dietary restriction and subsequent weight loss, common GI symptoms such as nausea, vomiting and bloating may disguise an ED.
Another challenge is learning how to ask questions to identify an ED. Our article provides a table with suggestions on how to incorporate the investigation of EDs in standard clinical practice. In general, using open-ended questions that allow patients to describe their diet habits, to indicate whether their symptoms are affected by food, and to express their feelings about eating, weight loss and body image can help provide clues about whether the patients have an ED.
Additionally, ED assessment measures often underestimate the incidence of EDs in the patient population that gastroenterologists see. This can be related to the fact that patients with EDs often underreport weight and shape concerns. And it's also worth noting that the tools for identifying classic EDs such as anorexia or bulimia have low specificity in identifying EDs in this population.
Your article also addresses some common misconceptions related to EDs. Can you describe some of those?
One misconception is that EDs affect mostly young, thin, white, affluent women. In fact, it is well documented that EDs affect individuals of all ages, genders, ethnicities and races, and socioeconomic statuses.
Another misconception is the idea that weight loss associated with EDs must be rapid and purposeful. ED behaviors and thought patterns may be present in patients, regardless of whether weight loss is slow or rapid, purposeful or accidental.
Another myth is that people with anorexia must appear underweight and cachectic. In fact, the Diagnostic and Statistical Manual of Mental Disorders DSM-5 no longer requires that patients meet a specific "low weight" threshold. Instead, clinicians should base their evaluation of a patient's weight loss and weight status on the physical health consequences of low weight and each patient's historic weight and growth history.
What can you tell us about the pathophysiology of EDs, and what are some risk factors and experiences that may predispose individuals to EDs?
The pathophysiology of EDs is complex and still not well understood. Family history or a genetic predisposition are risk factors. Temperamental and psychological characteristics (such as anxiety and harm avoidance, perfectionism, deficits in emotion regulation, and body dissatisfaction) and a history of weight stigma or weight-related teasing also can contribute. And several neurobiological factors, such as dysregulation of the hypothalamic-pituitary-adrenal axis, catecholamine disturbances, and brain-based dysfunction in the insular cortex and reward pathways, may play a role.
What did your research tell you about the relationship between EDs and GI diagnoses?
This is an important avenue to discuss, as gastroenterologists are in a unique position to assess weight loss, malnutrition and EDs, manage their complications, and attempt to normalize eating and weight. But we need to recognize that we may be causing a problem when we put patients on restricted diets to help manage conditions such as celiac disease, gastroparesis, irritable bowel syndrome and inflammatory bowel disease. When we reviewed studies on diet-controlled chronic illnesses, we found that individuals with these conditions have a higher risk of disordered eating and EDs than the general population.
We now understand that the relationship between EDs and GI disorders appears to be bidirectional. Some patients on restricted diets develop a maladaptive response, especially those who don't receive sufficient professional guidance about the timeline for these restrictions and expectations related to symptom improvement. Failure to follow up and evaluate the results of dietary intervention and plan the reintroduction of foods can also contribute to this maladaptive response. Given these facts, it is important to recommend dietary management only when appropriate. And when we recommend restricting or eliminating specific foods, we should provide follow-up care, support dietary flexibility and provide a referral to a dietitian if needed.
Established EDs can also lead to several neurological changes, some of which can then cause GI symptoms. Patients experiencing malnutrition and "starvation brain" due to any etiology can get caught in a vicious cycle where both GI symptoms and an ED coexist.
Can you provide some quick takeaways about the appropriate management of these patients in a gastroenterology setting?
Recent studies suggest that treatment using an aggressive feeding regimen to increase calories and support weight gain can lead to shorter hospitalizations and fewer complications. Temporary use of nasogastric tube feedings may be required in patients who cannot eat independently. Some patients may also require pharmacotherapy, which we describe in greater detail in the article. Overall, patients with EDs really benefit from a multidisciplinary care team that can include psychiatrists who specialize in EDs, general practitioners, dietitians and mental health counselors.
What additional research is needed to further clarify the issues discussed in your article?
We need to focus on efforts to screen for these disorders and identify them in a timely manner, and we need to refer these patients expeditiously to an effective, multidisciplinary treatment program. I hope that this article stimulates additional interest in researching this important topic.
For more information
Werlang ME, et al. Assessing for eating disorders: A primer for gastroenterologists.The American Journal of Gastroenterology. 2021;116:68.