Epilepsy's effect on cardiac rhythm and the autonomic nervous system

SUMMARY OBJECTIVE: Sudden unexpected death in epilepsy is the most common cause of death in young patients with epilepsy. The aim of this study was to evaluate changes in interictal electrocardiogram parameters and sympathetic skin responses as markers of autonomic dysfunction in patients with epilepsy and to determine their effects on the type and duration of epilepsy, frequency of seizures, and responses to treatment. METHODS: A total of 97 patients with epilepsy and 94 healthy controls were recruited. We recorded their clinical and demographic characteristics and analyzed sympathetic skin response latency and amplitude, electrocardiogram recordings, and seven cardiac rhythm parameters: P-wave duration, PR segment, QRS duration, QT interval, QT interval distribution, Tpe duration, and Tpe/QT interval ratio. RESULTS: P-wave durations, T-wave durations, QT and QT interval durations, and Tpe and sympathetic skin response latency were significantly longer among patients with epilepsy than the controls, and their heart rate was significantly lower. However, sympathetic skin response latency and heart rate were negatively correlated, and T-wave duration, QT duration, QT interval duration, and Tpe were positively correlated. CONCLUSION: Our results from interictal electrocardiograms indicate clinically significant arrhythmias among patients with epilepsy and the correlation of such arrhythmias with sympathetic skin responses. Thus, noninvasive tests that evaluate the autonomic system should be used to predict the risk of sudden unexpected death in epilepsy among patients with epilepsy.

Effect of Pharmacotherapy with Paroxetine on Biofeedback Measurement Variables in Panic Disorder Patients / 대한정신약물학회지

OBJECTIVE: There have been much effort to find reliable indicators predicting treatment response in panic disorder. This study aimed to find the effect of pharmacotherapy on biofeedback measurement variables in panic disorder patients. METHOD: We recruited 38 panic disorder patients (M:25, F:13) in the Samsung Medical Center, who were diagnosed by the ADIS-IV (Anxiety Disorder Interview Schedule-IV), and 33 normal control subjects (M:21 F:12). Panic patients were treated with paroxetine for 3 months. All subjects were assessed on forearm and frontal electromyography (EMG), electrodermal response (EDR), and skin temperature in baseline, stress, recovery phases using the Procomp & Biograph biofeedback instrument. Psychological measures such as Hamilton anxiety rating scale (HAM-A), Hamilton depression rating scale (HAM-D), Beck depression inventory (BDI), Spielberger state-trait anxiety inventory (STAI-S, STAI-T), and Anxiety sensitivity index (ASI) were also assessed. All measurements were performed at the beginning of the study and after 3 months of paroxetine treatment. RESULT: Panic patients had significantly higher scores on psychological measures such as HAM-A, HAM-D, BDI, STAI-S, STAI-T, and ASI (all p values<0.001) before treatment. After 3months of treatment, panic patients showed significant improvement on baseline EDR (z=-2.824, p=0.005), stress EDR (z=-2.691, p=0.007), and recovery EDR (z=-3.416, p=0.001). They also showed significant improvement on HAM-A, HAM-D, BDI, STAI-S, STAI-T, and ASI (all p values<0.001) after treatment. CONCLUSION: Electrodermal response, one of the biofeedback measurement variables, was suggested to be the possible indicator predicting treatment response in panic disorder.