Tremor associated with epilepsy: Etiology, prevalence, and impact on quality of life

Introduction: This study aimed to evaluate the frequency of tremor development in patients with epilepsy, its relationship with clinical and demographic characteristics, and its association with antiepileptic drugs (AEDs). The main research question of the study was whether the tremor accompanying epilepsy is solely a side effect of medication or a reflection of epileptic network dysfunction, and how this tremor affects patients' quality of life. Materials and Methods: A total of 200 patients diagnosed with epilepsy between 2022 and 2025 were retrospectively analyzed. Demographic characteristics, seizure types, epilepsy etiology, EEG and cranial MRI findings, AED use, and the presence of tremor were evaluated. The impact of tremor on quality of life was assessed using the Quality of Life in Essential Tremor Questionnaire (QUEST). Statistical analyses were performed using SPSS version 25.0, with a significance level of p < 0.05. Results: The mean age of the patients was 27.7 ± 8.6 years, and 52% were female. Tremor was observed in 34.5% of all patients. It was most frequent among those using valproic acid (60.4%), followed by levetiracetam (40.2%) and carbamazepine (33.3%), while lamotrigine users had a lower tremor rate (30.8%). Patients with lesional tremor had a significantly higher history of trauma, surgery, or cerebrovascular disease (p = 0.018). The most common etiology was idiopathic epilepsy (67%), and generalized tonic–clonic seizures (76%) were the predominant seizure type. Myoclonic seizureswere significantly more common in patients with tremor (p = 0.025). Epileptiform discharges were observed in 53–62%of tremor cases compared to 34.4% in those without tremor. Structural abnormalities such as cortical atrophy, gliosis, or old infarct scars were found in all cases of lesional tremor on MRI. QUEST results showed that tremor significantly limited fine motor skills, handwriting, and daily activities (mean score 46.2 ± 11.4). Conclusion: Tremor is a common comorbidity in epilepsy, occurring in approximately one-third of patients. Although valproic aciduse increases the risk, tremor cannot be explained solely as a drug-related side effect. The coexistence of tremor and epilepsy suggests shared neurophysiological mechanisms, including cortical hyperexcitability and cerebello-thalamo-cortical network dysfunction. Early recognition of tremor is crucial for individualized treatment planning and maintaining quality of life in epilepsy management. Keywords: Epilepsy, tremor, valproic acid, antiepileptic drugs, quality of life