Table_1_Prognosis of immune checkpoint inhibitor-induced myasthenia gravis: a single center experience and systematic review.DOCX

BackgroundImmune checkpoint inhibitors (ICI)-induced myasthenia gravis (MG) is an uncommon but potentially fatal neurotoxicity. We aim to help physicians familiarize themselves with the clinical characteristics of ICI-induced MG, facilitating early diagnosis and prompt intervention.
MethodsWe searched the Chinese People’s Liberation Army General Hospital medical record system from January 2017 to August 2023 for patients diagnosed with ICI-induced MG. We systematically reviewed the literature until August 2023 to identify all similar patients. We collected clinical information on these patients.
Results110 patients were identified, 9 from our institution and 101 from case reports. In our institution, Median age was 66 years (range: 49–79 years). 6 were males. The most common was lung cancer (n = 4). All patients had no previous history of MG and received PD-1 or PD-L1 inhibitors. The median time from ICI initiation to first MG symptoms was 4 weeks (range: 2–15 weeks). ICIs were discontinued in all patients. Most patients initially received high-dose corticosteroids, and their symptoms improved. Some patients are discharged with corticosteroids maintenance therapy. In addition, 55 patients (50%) with concomitant myositis and/or myocarditis and MG-induced mortality were more common in the myositis and/or myocarditis group (10.9% vs. 34.5%, p = 0.016). Overlap of myositis with MG (OR = 3.148, p = 0.009) and anti-AChR antibody positivity (OR = 3.364, p = 0.005) were both significantly associated with poor outcomes.
ConclusionOur study reveals the prognosis of ICI-induced MG and suggests that myositis and/or myocarditis are severe comorbidities of ICI-induced MG, emphasizing the importance of early diagnosis and clinical intervention.

**背景** 免疫检查点抑制剂（Immune Checkpoint Inhibitors, ICI）诱导的重症肌无力（Myasthenia Gravis, MG）是一种少见但可能致命的神经毒性反应。本研究旨在帮助临床医师熟悉ICI诱导型MG的临床特征，以助力早期诊断与及时干预。
**方法** 本研究检索了解放军总医院医学记录系统中2017年1月至2023年8月期间确诊为ICI诱导型MG的患者；同时系统检索截至2023年8月的相关文献，以识别所有同类患者，并收集这些患者的临床资料。
**结果** 本研究共纳入110例患者，其中9例来自本机构，101例来自已发表的病例报告。本机构患者的中位年龄为66岁（范围：49~79岁），男性6例；最常见的基础恶性肿瘤为肺癌（n=4）。所有患者既往无MG病史，且均接受了PD-1或PD-L1抑制剂治疗。从开始使用ICI至首次出现MG症状的中位时间为4周（范围：2~15周）。所有患者均停用了ICI治疗。多数患者初始接受大剂量糖皮质激素治疗后症状得到改善，部分患者出院后接受糖皮质激素维持治疗。此外，55例（50%）患者合并肌炎和/或心肌炎；合并肌炎和/或心肌炎组的MG相关死亡率显著更高（10.9% vs. 34.5%，p=0.016）。肌炎与MG共存（比值比OR=3.148，p=0.009）以及抗乙酰胆碱受体抗体（anti-AChR antibody）阳性（OR=3.364，p=0.005）均与不良预后显著相关。
**结论** 本研究阐明了ICI诱导型MG的预后特征，提示肌炎和/或心肌炎是ICI诱导型MG的严重合并症，强调了早期诊断与临床干预的重要性。