Kojima Yuta, Uzawa Akiyuki, Ozawa Yukiko, Yasuda Manato, Onishi Yosuke, Akamine Hiroyuki, Kawaguchi Naoki, Himuro Keiichi, Noto Yu-Ichi, Mizuno Toshiki, Kuwabara Satoshi
Neurology, Graduate School of Medicine, Chiba University, Chiba, Japan.
Neurology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan.
J Neurol Neurosurg Psychiatry. 2021 Sep;92(9):963-968. doi: 10.1136/jnnp-2020-325511. Epub 2021 Mar 25.
To investigate the association between changes in anti-acetylcholine receptor antibody (AChR Ab) levels induced by immunosuppressive treatment and myasthenia gravis (MG) prognosis at 1-year post-treatment in patients with MG.
We included 53 consecutive AChR Ab-positive patients with MG whose AChR Ab levels were remeasured within 100 days of initiating immunosuppressive treatment (median remeasuring time post-treatment: 71 (55-84) days). The AChR Ab level reduction rate (RR-AChRAb, %/day) adjusted for the time between treatment initiation, and AChR Ab level remeasurement was calculated as follows: (pretreatment-post-treatment AChR Ab level)/pretreatment AChR Ab level/days between therapy initiation and AChR Ab level remeasurement ×100. Participants were divided into two groups based on the cut-off value of RR-AChR Ab, determined using receiver operating characteristic analyses for achieving minimal manifestation (MM) or better status at 1-year postimmunosuppressive treatment. The Myasthenia Gravis Foundation of America postintervention status and MG activity of daily living (MG-ADL) score at 1-year post-treatment were compared between the two groups.
The RR-AChRAb cut-off value was 0.64%/day. The high RR-AChRAb group had a higher ratio of MM or better status (90% vs 65%, p=0.03) and lower MG-ADL score (median; 1 vs 2, p=0.04) than the low RR-AChRAb group. Kaplan-Meier analyses showed the early MM achievement in the high RR-AChRAb group (p=0.002, log-rank test).
High RR-AChRAb is associated with a favourable outcome at 1-year post-treatment. AChR Ab remeasurement within 100 days of therapy may be useful for predicting AChR Ab-positive MG outcomes at 1-year post-treatment.
探讨免疫抑制治疗引起的抗乙酰胆碱受体抗体（AChR Ab）水平变化与重症肌无力（MG）患者治疗后1年预后之间的关联。
我们纳入了53例连续的AChR Ab阳性MG患者，这些患者在开始免疫抑制治疗后100天内重新测量了AChR Ab水平（治疗后重新测量的中位时间：71（55 - 84）天）。根据治疗开始与AChR Ab水平重新测量之间的时间调整后的AChR Ab水平降低率（RR - AChRAb，%/天）计算如下：（治疗前 - 治疗后AChR Ab水平）/治疗前AChR Ab水平/治疗开始与AChR Ab水平重新测量之间的天数×100。根据RR - AChR Ab的截断值将参与者分为两组，该截断值通过接受者操作特征分析确定，以在免疫抑制治疗后1年达到最小表现（MM）或更好状态。比较两组在治疗后1年时美国重症肌无力基金会干预后状态和MG日常生活活动（MG - ADL）评分。
RR - AChRAb截断值为0.64%/天。高RR - AChRAb组达到MM或更好状态的比例高于低RR - AChRAb组（90%对65%，p = 0.03），且MG - ADL评分更低（中位数；1对2，p = 0.04）。Kaplan - Meier分析显示高RR - AChRAb组早期达到MM（p = 0.002，对数秩检验）。
高RR - AChRAb与治疗后1年的良好预后相关。在治疗后100天内重新测量AChR Ab可能有助于预测AChR Ab阳性MG患者治疗后1年的预后。
