Marlet I R, Andersen R K, Axelsen K H, Andersen L K, Vissing J, Witting N
Copenhagen Neuromuscular Center, Rigshospitalet, Copenhagen, Denmark.
J Neurol. 2024 Dec 12;272(1):29. doi: 10.1007/s00415-024-12807-1.
Early detection and diagnosis of myasthenia gravis (MG) is important to improve the chance of remission and overall prognosis. This study aims to investigate the factors affecting the diagnostic delay of MG thereby highlighting the challenges in the diagnostic process.
We conducted a retrospective study examining characteristics and factors involved in the diagnostic process of MG. We included 350 patients treated for MG at the Copenhagen Neuromuscular Unit (CNMC), between 1980 and 2022. A total of 315 patients had data on time to diagnosis, which was used to categorize them into an early-and a delayed diagnosis group, based on a median cut-off of 141 days. A separate analysis was conducted for the cases with an extremely delayed time to diagnosis exceeding the upper quartile range of 864 days (n = 28). Finally, change in time to MG diagnosis over time was identified.
The overall mean time to diagnosis was found to be 331 days (range: 5-4492 days). Patients who experienced a delayed diagnosis were significantly younger at onset (50.4 vs. 55.4 years, p-value < 0.05), and experienced higher frequency of asymptomatic periods (29% vs. 10%, p-value < 0.05). We found a delayed referral to specialists, extended time spent at specialists, and delayed initiation of paraclinical diagnostic tests. Additionally, in the delayed group we found extended time from the initial antibody (AB) evaluation to the first positive result (3.2 vs. 86.1 days, p-value < 0.05). Individuals in the early diagnosis group may be referred to stroke specialist earlier, however, this finding was not statistically significant (18 vs. 464 days, p-value 0.17). Gender, presenting symptom, final type of MG and socioeconomic status where not associated with delayed diagnosis. Generally, a trend of decreasing time to diagnosis over time was observed.
Younger age at onset, higher prevalence of asymptomatic periods, and a delayed positive AB titer test may be risk factors for a delayed MG diagnosis. Prompt referral to a stroke specialist may lead to an earlier diagnosis.
重症肌无力（MG）的早期检测和诊断对于提高缓解几率和总体预后至关重要。本研究旨在调查影响MG诊断延迟的因素，从而突出诊断过程中的挑战。
我们进行了一项回顾性研究，检查MG诊断过程中的特征和因素。我们纳入了1980年至2022年间在哥本哈根神经肌肉病科（CNMC）接受MG治疗的350例患者。共有315例患者有诊断时间的数据，根据141天的中位数临界值将他们分为早期诊断组和延迟诊断组。对诊断时间极延迟超过864天的上四分位数范围的病例（n = 28）进行了单独分析。最后，确定了随时间推移MG诊断时间的变化。
总体诊断平均时间为331天（范围：5 - 4492天）。经历延迟诊断的患者发病时明显更年轻（50.4岁对55.4岁，p值<0.05），且无症状期频率更高（29%对10%，p值<0.05）。我们发现转诊至专科医生延迟、在专科医生处花费的时间延长以及辅助临床诊断测试启动延迟。此外，在延迟组中，我们发现从最初抗体（AB）评估到首个阳性结果的时间延长（3.2天对86.1天，p值<0.05）。早期诊断组的个体可能更早被转诊至卒中专科医生，然而，这一发现无统计学意义（18天对464天，p值0.17）。性别、呈现症状、MG最终类型和社会经济地位与延迟诊断无关。总体而言，观察到诊断时间随时间呈下降趋势。
发病年龄较小、无症状期患病率较高以及AB滴度测试呈阳性延迟可能是MG诊断延迟的危险因素。及时转诊至卒中专科医生可能导致更早诊断。
