Epilepsy is often thought of as a disorder defined by dramatic convulsions—but much more can happen beneath the surface. In older adults especially, seizures may present subtly yet still leave lasting effects. Repeated focal onset impaired awareness seizures, non-convulsive events, and chronic seizure activity can gradually increase the risk of developing dementia over time. In this article, we’ll explore how epilepsy contributes to long-term brain changes that go beyond the seizures themselves, helping explain the cognitive decline often observed in these patients. 

Clarifying Seizure Types 

Before diving in, it’s important to clarify the type of seizures most relevant to cognitive decline. While generalized onset nonmotor seizures—commonly known as absence seizures—are often confused with “silent” seizures, they typically occur in childhood or adolescence and are not linked to long-term brain injury. In fact, patients with absence seizures may experience prolonged episodes without lasting damage once the seizures are controlled. 

By contrast, the seizures most often associated with aging, dementia, and cognitive decline are focal onset impaired awareness seizures. These can last longer, present as brief periods of confusion or disorientation, and often mimic early dementia symptoms—making them easy to overlook or misdiagnose. This blog focuses specifically on the focal seizure types relevant to older adults and their long-term neurological impact. 

How Does Epilepsy Lead to Dementia? 

While a single seizure may not cause lasting damage, chronic, uncontrolled epilepsy can result in significant structural and functional changes in the brain. Here’s how that process unfolds: 

• Neuronal Damage: Each seizure involves excessive neuronal firing, which can trigger cellular stress, excitotoxicity, and ultimately the loss of neurons. This progressive cell loss can impair memory, attention, and executive function 

• Abnormal Neural Circuitry: In epilepsy, the brain may try to heal itself after injury, but sometimes these repairs don’t go as planned. Instead of helping, they can create tangled or disorganized connections in the brain that interfere with normal thinking and memory functions (Allendorfer et al., 2019). 

• Hippocampal Sclerosis: One of the most common long-term changes seen in epilepsy patients is scarring in the hippocampus, a structure essential for learning and memory. This damage is especially prevalent in patients with focal onset impaired awareness seizures—a seizure type strongly linked to both cognitive impairment and dementia (Caramelli & Castro, 2005). 

White Matter and Network Connectivity 

In addition to damage in specific areas like the hippocampus, epilepsy can alter white matter integrity. White matter is essential for communication between brain regions. Disruptions here can reduce processing speed and complex reasoning, both of which are affected in dementia. MRI studies reveal that patients with long-standing epilepsy often show reduced white matter integrity, which may contribute to cognitive decline (Hatton et al., 2020). 

The Role of Neuroinflammation 

Epileptic seizures trigger inflammatory responses in the brain. Over time, this chronic neuroinflammation contributes to neurodegeneration. Researchers have found elevated levels of inflammatory cytokines in both epilepsy and dementia patients, suggesting that this pathway may be a critical link between the two conditions (Vezzani et al., 2011). This is why it is so important for seizures activity to be recognized and treated early. 

Medication Considerations 

While anti-seizure medications are crucial for seizure control, certain medications can have cognitive side effects. Medications like phenytoin and phenobarbital, used in older generations of epilepsy management, have been linked to memory impairment. Newer drugs such as levetiracetam and lamotrigine are more favorable, but it’s important to tailor therapy to minimize side effects. 

The Impact of Sleep Disturbance 

Sleep problems are common in epilepsy, and poor sleep itself is a well-established risk factor for cognitive decline. Sleep deprivation can worsen seizure control, creating a feedback loop that accelerates memory loss and cognitive impairment. 

The Emotional and Social Toll 

Long-term epilepsy can also affect mood and social engagement. Depression and anxiety are prevalent with recurrent seizures and can exacerbate cognitive difficulties.  

Additionally, social withdrawal due to fear of seizures can reduce mental stimulation, which is essential for maintaining cognitive health. 

Preventive and Protective Strategies 

• Consistent seizure control: Maintaining good seizure control is key to reducing long-term cognitive risks. 

• Neuroprotective lifestyle habits: Regular exercise, cognitive training, social activity, maintaining a balanced diet and keeping on top of general health may help preserve brain function. 

• Routine cognitive assessments: Periodic testing can help detect subtle changes early, allowing for timely intervention. 

For Families and Caregivers 

Caregivers can play a critical role by monitoring changes in cognition and behavior. Keeping a symptom diary and reporting these observations to healthcare providers can improve diagnosis and management. 

What’s Next in the Series? 

In the next post, we’ll dive deeper into the ways dementia can lead to seizures and why patients with cognitive decline are at higher risk of epilepsy. 

For more resources or to learn more about epilepsy and dementia, contact the Epilepsy Foundation of Northeastern New York at (518) 456-7501 or visit our website. 

References 

Allendorfer, J. B., et al. (2019). Functional connectivity and neuroplasticity in epilepsy. NeuroImage: Clinical. 

Arba, F., Rinaldi, C., Caimano, D., Vit, F., Busto, G., & Fainardi, E. (2017). Small vessel disease and epilepsy in elderly: A review. Seizure: European Journal of Epilepsy, 51, 106–111. https://doi.org/10.1016/j.seizure.2017.07.007 

Caramelli, P., & Castro, L. H. M. (2005). Temporal lobe epilepsy and memory. Epilepsy & Behavior. 

Hatton, S. N., et al. (2020). White matter abnormalities across different epilepsy syndromes in adults: A systematic review and meta-analysis. NeuroImage: Clinical. 

Vezzani, A., et al. (2011). The role of inflammation in epilepsy. Nature Reviews Neurology.