Department of Neurosurgery, New York University Langone Medical Center, New York, NY, USA.
Epilepsy Behav. 2011 Mar;20(3):478-83. doi: 10.1016/j.yebeh.2010.12.042. Epub 2011 Feb 5.
Studies have reported improved seizure control with increased duration of vagus nerve stimulation (VNS) but are prone to methodological biases. We analyzed the efficacy of VNS over time in patients with treatment-resistant epilepsy (TRE) who underwent VNS therapy 10 or more years.
We retrospectively reviewed 65 consecutive patients (29 females) who underwent VNS therapy ≥ 10 years. The mean age at VNS insertion was 30.0 years. Forty-four adults (≥ 18 years; 67.7%) and 21 children (32.3%) were included. Seizure frequency and antiepileptic drug (AED) regimens were recorded prior to VNS and, following VNS insertion, at 6 months, 1 year, 2 years, and every 2 years thereafter.
The mean duration of VNS therapy for this group was 10.4 years, and the mean decrease in seizure frequency at last follow-up was 76.3%. The mean reduction in seizures at 6 months and years 1, 2, 4, 6, 8, and 10 years was 35.7, 52.1, 58.3, 60.4, 65.7, 75.5, and 75.5%, respectively. Seizure frequency was significantly reduced from baseline at each of the recorded intervals (P<0.001). There was a trend toward increased AED burden in the latter years of the follow-up period.
Following a "ramp-up" and accommodation period throughout the initial 24 months after VNS implantation, seizure control improved slightly over the subsequent years of therapy and eventually stabilized. Variation in seizure frequency, however, was common, and frequent changes in AED regimens or stimulation parameters were likely an important and possibly synergistic component of seizure control.
已有研究报道，延长迷走神经刺激（Vagus nerve stimulation，VNS）的刺激时长可以改善癫痫发作的控制，但这些研究容易受到方法学偏倚的影响。我们分析了接受 VNS 治疗 10 年以上的耐药性癫痫（treatment-resistant epilepsy，TRE）患者中，VNS 随时间推移的疗效。
我们回顾性分析了 65 例连续接受 VNS 治疗≥10 年的患者（29 例为女性）。VNS 植入时的平均年龄为 30.0 岁。纳入 44 例成人（≥18 岁；67.7%）和 21 例儿童（32.3%）。在 VNS 植入前和植入后 6 个月、1 年、2 年以及此后每 2 年，记录癫痫发作频率和抗癫痫药物（antiepileptic drug，AED）方案。
该组患者的 VNS 治疗平均持续时间为 10.4 年，最后一次随访时的癫痫发作频率平均降低 76.3%。6 个月、1 年、2 年、4 年、6 年、8 年和 10 年时的癫痫发作平均减少率分别为 35.7%、52.1%、58.3%、60.4%、65.7%、75.5%和 75.5%。与基线相比，在所有记录的时间段内癫痫发作频率均显著降低（P<0.001）。在随访后期，AED 治疗负担呈增加趋势。
在 VNS 植入后的最初 24 个月的“适应期”之后，随着“逐渐适应期”的结束，癫痫控制在随后的治疗年数中略有改善，最终稳定下来。然而，癫痫发作频率的变化很常见，频繁改变 AED 方案或刺激参数可能是癫痫控制的一个重要且可能具有协同作用的因素。
