Department of Neurology, Graduate School of Medicine, Chiba University, Chiba.
Department of Global Clinical Research, Graduate School of Medicine, Chiba University, Chiba.
Ann Neurol. 2017 Nov;82(5):841-849. doi: 10.1002/ana.25087. Epub 2017 Nov 10.
Myasthenia gravis (MG) is an autoimmune disease mostly caused by autoantibodies against acetylcholine receptor associated with thymus abnormalities. Thymectomy has been proven to be an efficacious treatment for patients with MG, but postoperative myasthenic crisis often occurs and is a major complication. We aimed to develop and validate a simple scoring system based on clinical characteristics in the preoperative status to predict the risk of postoperative myasthenic crisis.
We studied 393 patients with MG who underwent thymectomy at 6 tertiary centers in Japan (275 patients for derivation and 118 for validation). Clinical characteristics, such as gender, age at onset and operation, body mass index, disease duration, MG subtype, severity, symptoms, preoperative therapy, operative data, and laboratory data, were reviewed retrospectively. A multivariate logistic regression with LASSO penalties was used to determine the factors associated with postoperative myasthenic crisis, and a score was assigned. Finally, the predictive score was evaluated using bootstrapping technique in the derivation and validation groups.
Multivariate logistic regression identified 3 clinical factors for predicting postoperative myasthenic crisis risk: (1) vital capacity < 80%, (2) disease duration < 3 months, and (3) bulbar symptoms immediately before thymectomy. The postoperative myasthenic crisis predictive score, ranging from 0 to 6 points, had areas under the curve of 0.84 (0.66-0.96) in the derivation group and 0.80 (0.62-0.95) in the validation group.
A simple scoring system based on 3 preoperative clinical characteristics can predict the possibility of postoperative myasthenic crisis. Ann Neurol 2017;82:841-849.
重症肌无力（MG）是一种主要由乙酰胆碱受体自身抗体引起的自身免疫性疾病，与胸腺异常有关。胸腺切除术已被证明对 MG 患者有效，但术后肌无力危象常发生，是一种主要并发症。我们旨在开发和验证一种基于术前临床特征的简单评分系统，以预测术后肌无力危象的风险。
我们研究了在日本 6 家三级中心接受胸腺切除术的 393 例 MG 患者（275 例用于推导，118 例用于验证）。回顾性分析了临床特征，如性别、发病年龄和手术年龄、体重指数、疾病持续时间、MG 亚型、严重程度、症状、术前治疗、手术数据和实验室数据。使用具有 LASSO 惩罚的多变量逻辑回归来确定与术后肌无力危象相关的因素，并分配评分。最后，在推导和验证组中使用自举技术评估预测评分。
多变量逻辑回归确定了 3 个预测术后肌无力危象风险的临床因素：（1）肺活量<80%，（2）疾病持续时间<3 个月，（3）术前球部症状。术后肌无力危象预测评分，范围为 0 至 6 分，在推导组中的曲线下面积为 0.84（0.66-0.96），在验证组中的曲线下面积为 0.80（0.62-0.95）。
基于 3 个术前临床特征的简单评分系统可以预测术后肌无力危象的可能性。Ann Neurol 2017;82:841-849。
