To quantify this progression, the researchers assessed the prevalence of epilepsy at several specific time points, ranging from a decade before the dementia diagnosis to five years following it. The data showed a clear upward trajectory: as the neurodegeneration associated with FTD progressed, so too did the likelihood of developing epilepsy. By the five-year mark following an FTD diagnosis, approximately 11% of patients had been diagnosed with epilepsy.
To ensure the accuracy of these figures, the researchers did not rely solely on formal epilepsy diagnoses. They also tracked the administration of anti-epileptic medications among the patient groups. The fact that the use of these medications was significantly higher in the FTD group further validates the study’s conclusions, suggesting that the seizures were frequent and severe enough to require pharmaceutical intervention. This multi-layered approach to data collection—combining diagnostic codes with medication history—strengthens the reliability of the results and underscores the magnitude of the issue.
Epilepsy might be left undiagnosed
The high prevalence of epilepsy in FTD patients brings to light a significant clinical hurdle: the difficulty of accurate diagnosis. In a patient already suffering from the behavioral or cognitive symptoms of frontotemporal dementia, a seizure may not look like the "grand mal" or tonic-clonic seizure typically associated with epilepsy in the popular imagination. Instead, these patients may experience focal seizures that manifest as sudden pauses in speech, repetitive movements, or brief periods of confusion—symptoms that are easily mistaken for the standard progression of FTD.
This overlap in symptoms creates a diagnostic "blind spot" that can lead to significant delays in treatment. When epileptic activity goes unrecognized, it is often left untreated, which can have a cascading effect on the patient’s overall health. Frequent, uncontrolled seizures can accelerate cognitive decline, increase the risk of physical injury from falls, and place an immense additional burden on caregivers.
"Identifying epilepsy is important because its treatment can improve patients’ functional capacity and quality of life," explains Associate Professor Eino Solje, the project’s principal investigator and Director of the University of Eastern Finland (UEF) Brain Research Unit. By stabilizing the electrical activity in the brain through appropriate medication, clinicians may be able to preserve a patient’s ability to perform daily tasks for a longer period, thereby extending their independence.
Beyond the immediate clinical benefits of treatment, the discovery opens up new frontiers for scientific inquiry. The strong correlation between the two conditions suggests that they may not be separate entities, but rather different manifestations of the same underlying problem. "Knowledge about the association between epilepsy and FTD raises new research questions: do these diseases share some pathophysiological mechanisms and could some FTD symptoms be caused by alterations in the specific electrical systems of the brain?" Solje asks.
