By: Sofia Arreguin
Epilepsy Defined
Described as a chronic disorder, epilepsy is the repeated occurrence of seizures as a result of abnormal electrical charges in the brain. Also labeled as a chronic disease, diabetes is known for its impaired control of an individual’s blood glucose levels. Although the two are distinguishable conditions, a link between the two seems to appear. It is established that individuals diagnosed with diabetes are more likely to have epilepsy. While it is not quite known why this connection exists, some researchers speculate that diabetes can cause changes within the brain, such as brain damage, which would make it more probable for epilepsy to develop (epsy, 2020).
Diabetic and Epileptic Symptoms
Despite their difference, both conditions seem to share a similar symptom: seizures. For epileptic patients, seizures are a result of considerable electrical activity in the brain; however, those with diabetes often experience seizures as a result of significantly low blood sugar levels (Seery, 2019).When looking towards symptoms, those of an epileptic seizure include shaking, staring blankly, or producing odd noises; and signs of a diabetic seizure include shaking, confusion, or speaking incoherently. Even though these symptoms may appear similar, there is a significant distinction between seizures (epsy, 2020). While epileptic seizures are often categorized as ‘generalized,’ meaning abnormal activity occurs on both sides of the brain, or ‘focal,’ where only a specific region of the brain is affected, this ‘diabetic seizure’ is also referred to as hypoglycemia, a term referring to the little amount of sugar in the blood. If left untreated, the patient could slip into a coma.
Causes
As mentioned, a lack of research on the connection between the two conditions results in unclear data. However, there are some determinants associated with their relationship, such as lifestyle choices, genetics, and chronic inflammation (D. Nadeem, et al., 2023). For example, when considering lifestyle choices, obesity is relatively common among individuals living with type 2 diabetes and insulin resistance, primarily because they lead a sedentary, or inactive, lifestyle. This lack of physical activity impairs brain health and neural functions, leading to an increased risk of seizures. Similarly, chronic stress plays a role in the development of diabetes and epilepsy, mainly by increasing cortisol levels and other stress-related hormones, which ultimately raise blood glucose levels and neuronal excitability, causing the occurrence of seizures. With chronic inflammation, the likelihood of acquiring epilepsy and diabetes is increased. For those with diabetes, inflammation tends to interfere with insulin signaling pathways, which are needed to direct glucose where needed within the body. This interruption often leads to insulin resistance, when the cells no longer respond to insulin and blood glucose levels are no longer regulated, resulting in elevated blood sugar levels. For people with epilepsy, inflammation fosters hyperexcitability within the brain, resulting in seizures. Genetically, the risk of a diabetic individual developing epilepsy increases if they have a family history of either condition. There are certain genes, or genetic pathways, such as KCNJ11 and ABCC8, that are linked to both epilepsy and diabetes (L. Gloyn, et al., 2006). Such genes are responsible for the secretion of insulin and brain development, and any modifications or mutations to these genes ultimately result in diabetes and epilepsy.
Interrelation
The epileptic symptom, namely seizures, tends to have an effect on glucose metabolism, which is especially important to those with diabetes. Seizures are said to produce cortisol and adrenaline, both stress-related hormones, that support the development of insulin resistance, giving way to hyperglycemia and weight gain (D. Nadeem, et al., 2023). These seizures also affect an individual’s autonomic nervous system by stimulating changes and, thus, an imbalance in blood pressure and heart rate. Consequently, this negatively influences the secretion of insulin since high blood pressure can heighten blood cell resistance, meaning it is more difficult for the blood to flow through the bloodstream and, therefore, difficult for insulin and glucose to be carried to the body’s tissues. Additionally, seizures can alter the brain’s neurotransmitter levels, furthering glycemic instability. For instance, these changes to neurotransmitter levels affect an individual’s satiety and hunger levels, which could mean either too little or too much food is consumed. Too much food results in a sudden increase in glucose, while too little food results in hypoglycemia.
Likewise, diabetes has its influence on epilepsy, specifically through the brain’s excitability and oxidative stress (D. Nadeem, et al., 2023). The heightened neuronal excitability and synaptic transmissions, communication between neurons, are characteristics of brain excitability within individuals with diabetes. High blood glucose levels, as seen in hyperglycemia, can disrupt the transmission of signals between nerves and the ability to process information. This results in a lower threshold for seizures, signifying a higher probability of repetitive seizures. Oxidative stress also impacts the brain’s neuronal system by giving rise to neuronal malfunction, which can result in worsened or more severe seizures.
Treatments
While treatments for epilepsy usually include anti-epileptic drugs, also known as AEDs, or surgery for more severe cases, diabetes can be treated by taking medication and insulin injections. These insulin injections are said to contribute to blood glucose control for those with epilepsy, without it affecting the efficiency of AEDs (D. Nadeem, et al., 2023). Diabetics can also take anti-diabetic drugs to stabilize their glycemic levels and reduce the possibility of seizures. However, there are some treatments that can be provided for both conditions, such as exercise and following through with the Ketogenic diet (Seery, 2019). Those with epilepsy and diabetes would benefit from maintaining a healthy weight, as physical activity strengthens glycemic control and the body’s absorption of insulin, while also reducing stress hormones, which may lower the frequency of seizures. The ketogenic diet, comprised of consuming a high-fat, low-carb diet, also benefits individuals with both conditions, as it lessens the amount of sugar within the body and is thought to lower the possibility of seizures by changing the brain’s chemical composition. This could be done through the diet’s ability to adjust inflammation, reduce oxidative stress, and shift the brain’s main source of energy from glucose, or sugar, to ketone bodies, which can yield more stable neurons, preventing seizures.
Conclusion
While there is not enough information to fully decipher and accurately establish the relationship between epilepsy and diabetes, it is clear there is some form of association, such as through their seizures. While one is caused by too little sugar in the bloodstream, another is caused by hyperexcitability in the brain. However, because their symptoms seem similar, it is beneficial for individuals with diabetes to get tested for epilepsy. This could help them find more effective treatments to protect against seizures and disruptions to their glycemic stability.
References:
Gloyn, A.L., et al. KCNJ11 activating mutations are associated with developmental delay, epilepsy and neonatal diabetes syndrome and other neurological features. European Journal of Human Genetics 14, 824-830 (2006). https://doi.org/10.1038/sj.ejhg.5201629
Let’s learn about the diabetes and epilepsy link. (2020, November 13). epsy. https://www.epsyhealth.com/seizure-epilepsy-blog/lets-learn-about-the-diabetes-and-epilepsy-link
Nadeem, M.D., et al. (2023). Seizing the Connection: Exploring the Interplay Between Epilepsy and Control in Diabetes Management. National Library of Medicine. https://doi.org/10.7759/cureus.45606
Seery, C. (2019, January 15). Epilepsy. Diabetes.co.uk. https://www.diabetes.co.uk/diabetes-complications/diabetes-and-epilepsy.html
