Joelsson Sara, Andersson Klara, Brannefors Petra, Klemetz Samuel, Gärdesmed Lovisa, Wennberg Elisabet, Hedström Anders, Asztely Fredrik, Zelano Johan, Strandberg Joakim
Department of Clinical Neurophysiology, Sahlgrenska University Hospital, Gothenburg, Sweden; Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden; Department of Neurology, member of ERN Epicare, Sahlgrenska University Hospital, Gothenburg, Sweden.
Epilepsy Behav. 2025 Jan;162:110151. doi: 10.1016/j.yebeh.2024.110151. Epub 2024 Nov 29.
Electroencephalography (EEG) is a standard investigation after a first unprovoked seizure but the diagnostic value in adults remains unclear. Our objective was to investigate the diagnostic value of EEG after a first unprovoked seizure in a population-based cohort in Gothenburg, Sweden.
This retrospective population-based study included adult patients referred by a neurologist for EEG after a first unprovoked seizure from August 2016 - December 2019 in the greater Gothenburg catchment area. In total 520 patients were included and followed in medical records for a median of 4.42 years (range 0.33-6.93). Primary outcome measures were epileptiform activity. Medical records were reviewed for the influence of EEG on clinical management. The frequency of epileptiform activity was calculated and compared in different subgroup analyses.
EEGs were recorded after a median of 70 days from the seizure. In total, 7.7 % had epileptiform activity, and 27.9 % had pathological slowing on their EEG. Seizure recurrence occurred in 33.7 % (29.6-37.8). Epileptiform activity predicted seizure recurrence with a recurrence risk of 82.5 % (70.7-94.3). The sensitivity of epileptiform activity was only 19.2 % (13.6-25.9) but the specificity was 98.0 % (95.9-99.2) and the relative risk of recurrence in presence of such activity was 2.8 (2.3-3.5). The EEG findings resulted in an alteration of diagnosis and/or medication in 4.4 % of the patients. Factors associated with epileptiform activity on EEG were younger age, EEG including sleep recording, generalized onset seizure, shorter time from seizure to EEG and longer duration of EEG recording.
The yield of EEG recorded with a longer latency after a first unprovoked seizure in adults was low. However, epileptiform activity highly predicted seizure recurrence and our results suggest that epileptiform activity on EEG could be explored further as a biomarker for defining epilepsy already after a first seizure.
脑电图（EEG）是首次无诱因癫痫发作后的一项标准检查，但在成年人中的诊断价值仍不明确。我们的目的是在瑞典哥德堡一个基于人群的队列中研究首次无诱因癫痫发作后脑电图的诊断价值。
这项基于人群的回顾性研究纳入了2016年8月至2019年12月在大哥德堡集水区因首次无诱因癫痫发作由神经科医生转诊进行脑电图检查的成年患者。总共纳入了520例患者，并在医疗记录中随访了中位数4.42年（范围0.33 - 6.93年）。主要结局指标是癫痫样活动。审查医疗记录以了解脑电图对临床管理的影响。计算癫痫样活动的频率并在不同亚组分析中进行比较。
癫痫发作后中位数70天进行了脑电图记录。总体而言，7.7%的患者有癫痫样活动，27.9%的患者脑电图有病理慢波。癫痫复发率为33.7%（29.6 - 37.8）。癫痫样活动可预测癫痫复发，复发风险为82.5%（70.7 - 94.3）。癫痫样活动的敏感性仅为19.2%（13.6 - 25.9），但特异性为98.0%（95.9 - 99.2），存在这种活动时复发的相对风险为2.8（2.3 - 3.5）。脑电图检查结果导致4.4%的患者诊断和/或药物治疗发生改变。与脑电图上癫痫样活动相关的因素包括年龄较小、脑电图包括睡眠记录、全面性发作起始、癫痫发作至脑电图检查的时间较短以及脑电图记录时间较长。
成年人首次无诱因癫痫发作后延迟较长时间记录的脑电图阳性率较低。然而，癫痫样活动高度预测癫痫复发，我们的结果表明，脑电图上的癫痫样活动可作为首次发作后定义癫痫的生物标志物进一步探索。
