By Ethan Messier
Introduction
An epileptic seizure can take many frightening forms. Symptoms of a seizure can vary dramatically, from violent jerking of the limbs to a loss of awareness characterized by a blank stare. For Jayce, an otherwise healthy toddler in Florida, his first seizure presented itself in a peculiar manner, with his head leaning forward and shoulders tensed up. Over the following months, Jayce’s mother noticed that he seemed to be having these episodes more often, each time characterized by a stiffening of his body. Though he did not exhibit the dramatic shaking and convulsions one typically associates with a seizure, Jayce was diagnosed with infantile spasms, a subset of epilepsy (Johns Hopkins Medicine).
A Michigan dietician, Samantha Barash, shares her story of battling an eating disorder. After developing a fixation with food in 8th grade, Barash began extreme dieting and food restriction. She recalls the fixation spiraling into a mental illness, “You come into this with a fascination with food and then you start to truly think food is the most important thing in the world” (Richardson & Sousanis, 2024). According to ANAD, the National Association of Anorexia Nervosa and Associated Disorders, 28.8 million Americans will have an eating disorder in their lifetime. Every 52 minutes, someone in the United States dies as a direct result of an eating disorder (ANAD).
Though epilepsy and eating disorders may seem to have little in common, the overlap and intersection of the two disease groups is a fascinating topic of recent medical interest. In current medical literature, physicians and scientists are investigating the link between these two diseases, particularly in young people.
The Correlation
According to the Cleveland Clinic, a comorbidity is defined as a medical condition that occurs simultaneously alongside a “primary diagnosis”. A disease process can be associated with one or more comorbidities. Often, in the context of epilepsy and eating disorders, eating disorders are considered an increasingly common comorbidity in patients with epilepsy as the primary diagnosis. The breadth of research in this area focuses on adolescents, where the correlation between the two diseases is distinctly pronounced.
In a longitudinal study of nearly 400 patients who visited Boston clinics and hospitals over the course of a decade noted that “EDs (eating disorders) occur at higher rates in female and male adolescents with epilepsy… compared to a large sample of adolescents seen in clinics in the same medical center” (Latzer, et al, 2023). The data from this study showed that there is a marked difference in the presence of eating disorders in epilepsy patients than in patients without a seizure disorder. This data was not exclusive to a specific type of seizure or any specific eating disorder and included those being treated at the clinic for anorexia nervosa, bulimia nervosa, and binge eating disorder.
Though correlation must not be erroneously inferred to indicate causation, the same study provides potential explanations for the commonality of eating disorders as a comorbidity in epilepsy patients. The study touches on eating disorder research, which often attributes environmental stressors and societal influence as common triggers in eating disorder patients. In epilepsy patients, frequent visits to medical facilities, intense drug therapy, and the social impact of living with a seizure disorder are believed to bring about negative self image and body dissatisfaction, a key contributor to the development of an eating disorder (Latzer, et al, 2023).
Mice: Opening the Door for a Biochemical Investigation
A study from the University of California, San Francisco, takes a unique approach to investigate the link between seizure disorders and disordered eating: rodents. Scientists aimed to investigate the link between a neurotransmitter called serotonin (known chemically as 5-HT) and the processes of the nervous system in mice. Put simply, a neurotransmitter works by sending a message throughout the brain that activates a process within the rest of the body. A chemical binds to a receptor on a brain cell, triggering a response. Using genetic engineering, researchers were able to produce mutant mice that lacked the receptors needed for serotonin to perform its normal functions throughout the brain and body.
The study showed that mutant mice who lacked serotonin receptors exhibited “abnormal control of feeding behavior” (Tecott et al, 1995). These mice were also more prone to spontaneous seizures. Though this study focuses specifically on mice, it opens the door for an investigation into a potential molecular explanation for the correlation between seizures and eating disorders.
A Multi-Purpose Drug
One final intersection between epilepsy and eating disorders worth investigating is the unique ability for anti-epileptic drugs to be used as an effective treatment for eating disorders. A collaborative study authored by Boston and Ohio scientists notes that one drug commonly prescribed for epilepsy management, topiramate, “appears to have the broadest spectrum of action as an anti-binge eating, anti-purging and weight loss agent” (McElroy et al, 2009).
The study provides several suggestions as to why some anti-epileptic drugs (AEDs) prove to be useful in treating eating disorders. Most notably, AEDs typically have broad molecular targets within the brain, and have been used for decades to treat other mental illnesses like anxiety and bipolar disorder, which are common comorbidities in eating disorder patients. Additionally, many AEDs have distinct side effects on body weight. Physicians have recommended prescribing AEDs with weight loss side effects in patients with eating disorders who binge eat or are overweight, and those with the opposite effect for patients with anorexia nervosa who are underweight (McElroy et al, 2009).
Looking Forward
Though scientists have made great strides in understanding the correlation between epilepsy and eating disorders, there is still so much to be uncovered about the true cause for this overlap. Furthermore, there is much progress yet to be made in the treatments for both groups of diseases individually. There is no known cure for epilepsy, and up to 30% of epilepsy patients are unable to manage their seizures with the best methods currently available. While eating disorder patients often make a successful recovery, every patient is different, and there is no “miracle cure”. The intersection between these two diseases is fascinating, and of great personal importance to me. I look forward to a day where the link between EDs and epilepsy is well understood, and this is surely a niche of neuroscience research I will be keeping a keen eye on.
References
Tokatly Latzer, I., Richmond, T. K., Zhang, B., & Pearl, P. L. (2023). Eating disorders occur at high rates in adolescents with epilepsy and are associated with psychiatric comorbidities and suicidality. Epilepsia, 64(11), 2982–2992. https://doi.org/10.1111/epi.17759
Tecott, L. H., Sun, L. M., Akana, S. F., Strack, A. M., Lowenstein, D. H., Dallman, M. F., & Julius, D. (1995). Eating disorder and epilepsy in mice lacking 5-HT2c serotonin receptors. Nature, 374(6522), 542–546. https://doi.org/10.1038/374542a0
McElroy, S. L., Guerdjikova, A. I., Martens, B., Keck, P. E., Jr, Pope, H. G., & Hudson, J. I. (2009). Role of antiepileptic drugs in the management of eating disorders. CNS drugs, 23(2), 139–156. https://doi.org/10.2165/00023210-200923020-00004
Epilepsy: Jayce’s story. Johns Hopkins Medicine. (n.d.). https://www.hopkinsmedicine.org/health/conditions-and-diseases/epilepsy/epilepsy-syndromes-in-children/patient-story-jayce
C. C. medical. (n.d.). What are comorbidities?. Cleveland Clinic. https://my.clevelandclinic.org/health/articles/comorbidities
Richardson, A., & Sousanis, A. (2024). “all we hear about are the diets.” starving, gorging, fighting to heal amid eating disorders. USA Today. https://www.usatoday.com/story/news/health/2024/04/06/eating-disorder-recovery-stories/73103691007/
Eating disorder statistics: ANAD - National Association of Anorexia Nervosa and associated disorders. ANAD National Association of Anorexia Nervosa and Associated Disorders. (2024, April 3). https://anad.org/eating-disorder-statistic/
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