肌萎缩侧索硬化症CMAP波幅与ALSFRS-r评分的相关性分析
Correlation between compound muscle action potential amplitude and revised amyotrophic lateral sclerosis functional rating scale in amyotrophic lateral sclerosis

摘要：目的 分析肌萎缩侧索硬化症(ALS)患者运动神经传导复合肌肉动作电位(compound muscle action potential, CMAP)波幅下降与改良肌萎缩侧索硬化功能评分(revised amyotrophic lateral sclerosis functional rating scale, ALSFRS-r)的相关性。方法 258例ALS患者进行常规运动神经传导测定，对上、下肢不同神经CMAP波幅下降进行分析，并探讨其与ALSFRS-r评分及各亚项评分的关系。结果 大多数患者出现运动神经传导异常，其中正中神经、尺神经、腓总神经和胫神经传导异常均以CMAP波幅减低最为常见(14.80%～59.90%)，然后依次为末端运动潜伏期？？(distal？？ motor latency, DML)延长(1.83%～25.00%)、CMAP未引出(2.23%～10.55%)和运动传导速度(motor conduction velocity, MCV)减慢(0～14.36%)。相关分析显示，正中神经、尺神经、腓总神经和胫神经的CMAP波幅与ALSFRS-r呈正相关(r=0.333，P<0.001；r=0.284，P<0.001；r=0.189，P=0.002；r=0.253，P<0.001)。Logistic回归分析显示，正中神经和胫神经的CMAP波幅与ALSFRS-r呈正相关，ALSFRS-r颈膨大亚项得分与正中神经CMAP波幅明显相关，而与尺神经CMAP波幅无相关性；ALSFRS-r腰膨大评分与胫神经和腓总神经CMAP波幅均有相关性。结论 ALS患者运动神经传导异常以CMAP波幅下降最多见。它是一种有效的不可忽视的客观判断ALS病情严重程度的电生理指标，不同神经的CMAP波幅下降对判断颈膨大和腰膨大支配肌肉功能损害程度与ALSFRS-r评分中各个亚项评分具有同等评估效能。
ABSTRACT: Objective To explore the correlation between compound muscle action potential (CMAP) amplitude and Revised Amyotrophic Lateral Sclerosis Functional Rating Scale (ALSFRS-r) in amyotrophic lateral sclerosis (ALS). Methods Standard motor nerve conduction studies were performed in 258 ALS patients. We analyzed the decrease of CMAP amplitude in different motor nerves in the four limbs and discussed the relationship between the CMAP amplitude and ALSFRS-r score and the score of each subitem. Results Motor nerve conduction abnormalities were present in a majority of the patients with decreased CMAP amplitude in the median nerve, ulnar nerve, peroneal nerve and tibial nerve as the most common form (14.80%-59.90%)，followed by prolonged DML (1.83%-25.00%), absence of CMAP (2.23%-10.55%), and decreased MCV (0-14.36%). Significant positive correlation was found between CMAP amplitude of the median, ulnar, peroneal and tibial nerves and ALSFRS-r (r=0.333, P<0.001; r=0.284, P<0.001; r=0.189, P=0.002; r=0.253, P<0.001). Logistic regression analysis showed significant correlation between the ALSFRS-r score and the median and tibial nerve CMAP amplitude. Logistic regression analysis showed significant correlation between the cervical enlargement score of ALSFRS-r and median nerve CMAP amplitude, the lumbar enlargement score of ALSFRS-r and CMAP amplitude of peroneal and tibial nerves, but no correlation with ulnar nerve CMAP amplitude. Conclusion Motor nerve conduction is abnormal in a majority of ALS patients with decreased CMAP amplitude as the most common form. It is a validated and objective electrophysiological instrument for monitoring the severity of disability in ALS patients. The decrease of CMAP amplitude in different motor nerves