The Characteristics And Associated Factors Of Tremor In Patients With Epilepsy

PART I Clinical features of tremor in patients with epilepsy Objective: To investigate the incidence and clinical characteristics of tremor in patients with epilepsy.Methods: Patients with epilepsy who visited the department of Neurology at Xinhua hospital affiliated to Shanghai Jiao Tong University from September 2018 to September2019 were studied.All patients were registered for general information,seizures and medications situation.All patients with epilepsy were evaluated by the Clinical Rating Scale for Tremor(CRST).The characteristics of patients taking different drugs were compared.Patients were also evaluated by the Quality of Life in Epilepsy(QOLIE-31)to analyze the effects of tremor on the quality of life in patients with epilepsy.Results:(1)80 patients with epilepsy were enrolled.There were 22(27.5%)patients with tremor finding by self-reported complaint and(or)physical examination by clinicians.The tremor mainly manifested as postural tremor in the upper limbs,and a few patients also showed resting tremor.Tremor of upper limbs in 63.6% patients were symmetric.Tremor was also seen in tongue,head,and lower limbs.(2)The incidence of tremor was significantly higher in patients taking VPA than taking other AEDs(35.1% vs 8.7%,P =0.017).And the score of part A and total score of CRST in patients taking VPA were higher,the difference was statistically significant(Part A: P = 0.018;total score: P =0.039).(3)The total score and scores of each sub-item of QOLIE-31 in the patients with tremor were lower than those without tremor,but the differences were not statistically significant.The social function score in the QOLIE-31 was negatively correlated with the score of part A and total score of CRST.Conclusions: Tremor was mainly manifested as postural tremor in the upper limbs in patients with epilepsy,most of which were bilaterally symmetrical.The incidence of tremor was higher in patients taking VPA than other AEDs.Social function was negatively correlated with severity of tremor.PART II Electrophysiological characteristics of tremor in patients with epilepsyObjective: To investigate the electrophysiological characteristics of tremor in patients with epilepsy.Methods: Patients with epilepsy who visited the department of Neurology at Xinhua hospital affiliated to Shanghai Jiao Tong University from September 2018 to September 2019 were enrolled.All patients were collected for general information,seizures and medications situation.All patients with epilepsy were examined by electromyography(EMG).Results: The EMG examination revealed that 51 patients(63.8%)had tremor in the upper limbs.The incidence was 2.3 times as much as clinical evaluation.Among them,42 patients(82.3%)manifested postural tremor,32 patients(62.7%)manifested resting tremor.Over half of the patients(50.9%)have symmetrical tremor.The peak frequency of postural tremor in patients with epilepsy was 7.2 ± 4.1Hz,and mainly showed synchronous burst pattern.The peak frequency of resting tremor in patients with epilepsy was 5.3 ± 2.2Hz,and mainly showed alternating burst pattern.There were 29 patients(56.9%)had no tremor complaint,and no tremor was detected during physical examination.Patients with perceivable tremor took more medicines than patient with imperceptible tremor(P = 0.042).Patients with resting tremor were older than patients without resting tremor,and had later age of onset,and took more medication.Conclusions: The EMG is a more sensitive and objective examination method,which can detect tremor that was not yet noticed by patients with epilepsy.Most patients showed postural tremor,and some patients showed resting tremor.The peak frequency of postural tremor was 7.2 ± 4.1Hz,and the EMG burst pattern was mainly synchronous;the peak frequency of resting tremor was 5.3 ± 2.2Hz,and the EMG burst pattern was mainly alternating.PART Ⅲ Associated factors of tremor in patients with epilepsyObjective: To explore the related factors affecting the occurrence of tremor in patients with epilepsy.Methods: Patients with epilepsy who were visited in the department of Neurology at Xinhua hospital affiliated to Shanghai Jiao Tong University from September 2018 to September 2019 were enrolled.All patients were collected for general information,seizures and medications situation.All patients were asked for a detailed medical history and physical examination.Patients were divided into two groups based on whether had tremor complaints and(or)physical examination revealed tremor.Univariate analysis and multivariate analysis were used to explore the relevant factors affecting the occurrence of tremor.Results: Univariate analysis showed that the number of AEDs taken by patients with tremor was significantly higher than those without tremor,the difference was statistically significant(P = 0.016).20 patients(90.9%)with tremor were treated with VPA,and only 37 patients(63.8%)without tremor taking VPA,the difference was statistically significant(P = 0.017).The duration of taking VPA in the patients with tremor was significantly longer than those without tremor(P = 0.012).Multivariate analysis showed that large number of AEDs and long duration of taking VPA were significantly related to the occurrence of tremor in patients with epilepsy.Conclusions: Large number of medications and long duration of taking VPA might be the mainly associated factors for occurrence of tremor in patients with epilepsy.