Cardiac Complications of Eating Disorders 

Cardiac Dysfunction In Eating Disorders

Anorexia nervosa and bulimia nervosa are different types of eating disorders. Eating disorders are psychological conditions that involve complicated relationships with body image and food. People with these conditions develop unhealthy eating habits and related mental and physical complications. Individuals with eating disorders have significantly elevated mortality rates, with the highest rates occurring in those with anorexia nervosa.

Although suicide represents nearly half the mortality in patients with eating disorders, many of the remaining deaths are likely impacted by the cardiovascular complications of eating disorders including bradyarrhythmias, cardiac structural changes, and abnormal electrical conduction, along with electrolyte abnormalities and hypoglycemia.

Anorexia Nervosa Cardiac Complications

Anorexia nervosa (AN) is an eating disorder characterized by abnormally low body weight, an intense fear of gaining weight and a distorted body perception. People with anorexia place a high value on controlling their weight and shape, using extreme efforts that significantly interfere with their lives. They usually severely restrict their food intake to prevent weight gain or continue losing weight. Cardiac abnormalities among patients with AN are present not only before treatment but can also arise during the refeeding process.

Bradycardia

Occurring in up to 95% of patients, bradycardia (a heart rate less than 60 beats per minute), is one of the most common complications observed in patients with anorexia nervosa. Clinically significant bradyarrhythmias may represent a competing underlying mechanism for this population's high risk of sudden death.

Low heart rate may result from an increased vagal tone in the body's attempt to conserve energy; however, findings on this topic have been inconsistent. Severe and prolonged bradycardia can cause fainting (syncope), chest discomfort, shortness of breath, fatigue, palpitations, and other nonspecific symptoms. Pauses or stops in the heartbeat (aka sinus pauses) can predispose to more sinister arrhythmias that can become even more prominent with increased severity and frequency of bradycardia. 

The "Athletic Heart" 

Many patients with an eating disorder may attribute their low heart rate to perceived physical fitness. Since most physicians receive no specific training in identifying or treating eating disorders, it can be easy to take this explanation at face value. However, athletes have a low resting heart rate with only slight increases during activity. In contrast, malnourished patients have a low resting heart rate but exhibit tachycardia (elevated heart rate) with minimal activity.

Hypotension

Hypotension, or low blood pressure, is another frequent manifestation of malnutrition. Patients with abnormally low blood pressure can experience dizziness, nausea, fatigue blurred vision, and syncope, sometimes resulting in severe bodily injuries. Many patients may also receive a diagnosis of POTS (postural orthostatic tachycardia syndrome), although this is often just an extreme manifestation of the malnutrition.

Structural Heart Disease

Structural heart disease in patients with eating disorders is attributable to wasting of the cardiac muscle (i.e., myocardial atrophy). The cardiac atrophy also creates valvular dysfunction, specifically mitral valve prolapse, sometimes causing chest discomfort and palpitations; the valve itself remains healthy but is more lax related to the cardiac atrophy. Cardiac remodeling and scarring can also develop, potentially increasing the risk for sinister arrhythmias.

Pericardial Effusion

The exact mechanism of pericardial effusion (a buildup of too much fluid in the saclike structure around the heart) in eating disorders is poorly understood but may be related to thyroid hormone levels and/or reduced pericardial fat. Patients with pericardial effusions appear to have a lower BMI (body mass index), lower triiodothyronine, and a longer duration of hospitalizations. In rare instances, this fluid buildup can encroach upon cardiac hemodynamics, impacting cardiac filling (cardiac tamponade).

Bulimia Nervosa Cardiac Complications

Bulimia nervosa is a severe, potentially life-threatening eating disorder. People with bulimia may secretly binge — eating large amounts of food with a loss of control over the eating — and then purge, trying to get rid of the extra calories in an unhealthy way. Patients may self-induce vomiting or misuse laxatives, weight-loss supplements, diuretics or enemas after bingeing or exercising excessively to lose weight.

Similar to AN, patients with bulimia nervosa are at risk for abnormal heart rhythms but also seem to be at increased risk for long-term cardiac complications such as ischemic heart disease, thereby increasing the risk for heart attacks, and atherosclerosis, or the build up of fats and cholesterol in the arterial walls. Both of these diseases are associated with increased mortality. 

Hypokalemia

Patients who engage in purging, whether they have bulimia nervosa or the binge-purge subtype of anorexia nervosa, are likely to have electrolyte abnormalities. Hypokalemia is one of the most severe complications for patients, as it can lead to various cardiac complications, including cardiac arrhythmias (irregular heartbeat), conduction disturbances and muscle weakness. Hypomagnesemia is also likely to develop, especially in those who misuse diuretics or alcohol, and can work synergistically with hypokalemia to increase the risk for cardiac conduction abnormalities.

Emetine Toxicity

While patients can use their fingers to induce vomiting, some individuals with bulimia have historically induced vomiting by using medications. To induce vomiting, patients who use ipecac, an anti-parasitic and rapid-acting emetic, may experience cardiac complications due to chronic ingestion of ipecac's active ingredient, emetine. Emetine has a long half-life and can accumulate in the body over time, causing irreversible damage to cardiac myocytes, leading to severe congestive heart failure, ventricular arrhythmias or even death. 

Avoidant Restrictive Food Intake Disorder (ARFID) Cardiac Complications

ARFID is a feeding disturbance characterized by a persistent failure to meet appropriate nutritional or energy needs. Unlike other eating disorders, those with ARFID have no preoccupation with weight or shape. While empirical data on ARFID complications is still budding, malnutrition associated with ARFID may cause similar complications as other eating disorders, like bradycardia.

Atypical Anorexia Nervosa (A-AN) Cardiac Complications

A-AN mirrors anorexia nervosa, but those suffering from it are at a normal or above normal weight. Despite the idea that complications only occur at very low weights, those with A-AN suffer from many of the same complications their underweight counterparts do, including hypotension and bradycardia, although research has heretofore only been completed in adolescents regarding cardiac complications.

Are Heart Issues from Eating Disorders Reversible?

Thankfully, many of the cardiac complications from eating disorders are reversible. Most patients will find complications resolved after weight restoration, including bradycardia, hypotension, mitral valve prolapse, and pericardial effusion.  

How Cardiovascular Problems Affect Eating Disorder Treatment

Severe cardiac complications necessitate treatment at a medical stabilization unit where patients require close cardiac monitoring and slow refeeding to minimize the risk of refeeding syndrome and exacerbating existing complications. Unlike residential treatment programs for eating disorders, medical stabilization programs have the telemetry support, which allows for 24:7 cardiac monitoring, needed to assess symptom progression and improvement, as well as same-day lab results that are used to monitor key electrolyte levels affecting the functioning of the heart. 

Compared to standard hospital units, specialized eating disorder medical stabilization units have the expertise to prevent and monitor medical complications, including refeeding syndrome. Medical stabilization units also provide a breadth of other eating disorder levels of care, preparing patients to continue their journey to recovery.

Resources

• Crow SJ, Salisbury JJ, Crosby RD, Mitchell JE. Serum electrolytes as markers of vomiting in bulimia nervosa. Int J Eat Disord 1997;21(1):95-8.
• Farasat M, Watters A, Bendelow T, Schuller J, Mehler PS, Krantz MJ. Long-term cardiac arrhythmia and chronotropic evaluation in patients with severe anorexia nervosa (LACE-AN): A pilot study. J Cardiovasc Electrophysiol 2020;331:432-9.
• Gibson D, Mehler PS. Cardiac tamponade in anorexia nervosa: An argument for conservative management. Ann Case Rep 2023;8(4):1406.
• Mehler PS and Andersen AE (Eds). Eating Disorders: A comprehensive guide to medical care and complications (4^th ed). 2022. John Hopkins University Press.
• Mehler PS, Watters A, Joiner T, Krantz MJ. What accounts for the high mortality of anorexia nervosa? Int J Eat Disord 2022;55:633-6.
• Nitsch A, Watters A, Manwaring J, Bauschka M, Hebert M, Mehler PS. Clinical features of adult patients with avoidant/restrictive food intake disorder presenting for medical stabilization: A descriptive study. Int J Eat Disord 2023;56:978-90.
• Sachs KV, Harnke B, Mehler PS, Krantz MJ. Cardiovascular complications of anorexia nervosa: A systematic review. Int J Eat Disord 2016;49(3):238-48.
• Tith RM, Paradis G, Potter BJ, et al. Association of bulimia nervosa with long-term risk of cardiovascular disease and mortality among women. JAMA Psychiatr 2020;77(1):44-51.
• Yahalom M, Spitz M, Sandler L, Heno N, Roguin N, Turgeman Y. The significance of bradycardia in anorexia nervosa. Int J Angiol 2013;22:83-94

Last Reviewed: February 2024 by Dennis Gibson, MD, FACP, CEDS