OBJECTIVE Vagal nerve stimulator (VNS) implantation at an early age seems to lead to improved quality of life and cognitive outcome. The aim of this analysis is to evaluate whether specific patient or seizure characteristics might lead to better seizure control, cognitive outcome, and higher quality of life in children undergoing VNS implantation. METHODS Primary outcome measure was reduction in seizure frequency. Secondary outcome measures were epilepsy outcome assessed by McHugh and Engel classifications, reduction in antiepileptic drugs (AED), developmental and cognitive outcome, as well as quality of life assessed through the pediatric quality of life (PEDSQL™) questionnaire and care giver impression (CGI) scale. Forty-five consecutive children undergoing VNS implantation were analyzed for the following subgroups: age (categorized to 1-2 years old, 3-5 years old, 6-12 years old, and 13-18 years old), sex, underlying cause (categorized to idiopathic, encephalitis, stroke, syndromic), duration of preoperative seizures (dichotomized to under or above 89 months, corresponding to the median of the whole cohort), and preoperative seizure frequency (dichotomized to under and above 360 seizures per month). RESULTS Encephalitis as the underlying cause for seizures was the only variable significantly associated with higher reduction rate of seizure frequency. Patients with VNS implantation at the age of ≤ 2 years showed a strong association with better developmental and cognitive outcome, as well as quality of life. Shorter duration of preoperative seizures and higher preoperative seizure frequency showed a strong association with better developmental outcome, as well as quality of life. Engel outcome scores were significantly better in patients with epilepsy due to encephalitis (100% Engel I-III). However, patients with epilepsy due to encephalitis showed significantly higher complication rates (71.4%, p = 0.045). CONCLUSIONS Children suffering from epilepsy due to encephalitis show higher seizure reduction rates after VNS implantation when compared with children suffering from epilepsy due to other causes. Developmental and cognitive outcomes as well as quality of life of children undergoing VNS implantation is strongly associated with shorter duration of preoperative seizures and implantation at a young age.

中文翻译：

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儿童迷走神经刺激器植入后癫痫发作和认知结果的亚组分析。

目标 迷走神经刺激器 (VNS) 在早期植入似乎可以改善生活质量和认知结果。该分析的目的是评估特定患者或癫痫发作特征是否可能导致接受 VNS 植入的儿童更好地控制癫痫发作、认知结果和更高的生活质量。方法 主要结果测量是癫痫发作频率的减少。次要结果测量是通过 McHugh 和 Engel 分类评估的癫痫结果、抗癫痫药物 (AED) 的减少、发育和认知结果，以及通过儿科生活质量 (PEDSQL™) 问卷和护理人员印象 (CGI) 评估的生活质量） 规模。针对以下亚组分析了 45 名连续接受 VNS 植入的儿童：年龄（分类为1-2岁、3-5岁、6-12岁和13-18岁）、性别、根本原因（分类为特发性、脑炎、中风、综合征）、术前癫痫发作持续时间（分为低于或高于 89 个月，对应于整个队列的中位数）和术前癫痫发作频率（分为低于或高于每月 360 次癫痫发作）。结果脑炎作为癫痫发作的根本原因是唯一与癫痫发作频率降低率显着相关的变量。≤ 2 岁时植入 VNS 的患者与更好的发育和认知结果以及生活质量密切相关。更短的术前癫痫发作持续时间和更高的术前癫痫发作频率与更好的发育结果密切相关，以及生活质量。因脑炎引起的癫痫患者的 Engel 结果评分明显更好（100% Engel I-III）。然而，脑炎所致癫痫患者的并发症发生率显着升高（71.4%，p = 0.045）。结论 与其他原因导致癫痫的儿童相比，脑炎导致癫痫的儿童在植入 VNS 后表现出更高的癫痫发作减少率。接受 VNS 植入的儿童的发育和认知结果以及生活质量与较短的术前癫痫发作持续时间和年轻时植入密切相关。脑炎所致癫痫患者的并发症发生率显着升高（71.4%，p = 0.045）。结论 与其他原因导致癫痫的儿童相比，脑炎导致癫痫的儿童在植入 VNS 后表现出更高的癫痫发作减少率。接受 VNS 植入的儿童的发育和认知结果以及生活质量与较短的术前癫痫发作持续时间和年轻时植入密切相关。脑炎所致癫痫患者的并发症发生率显着升高（71.4%，p = 0.045）。结论 与其他原因导致癫痫的儿童相比，脑炎导致癫痫的儿童在植入 VNS 后表现出更高的癫痫发作减少率。接受 VNS 植入的儿童的发育和认知结果以及生活质量与较短的术前癫痫发作持续时间和年轻时植入密切相关。