抗MDA5抗體陽性皮肌炎患者的死亡風險因素分析：單中心回顧性研究

Risk factors for mortality in patients with anti-MDA5 antibody-positive dermatomyositis: a single center retrospective study

研究目的：本研究旨在識別皮肌炎患者中抗黑色素瘤分化相關蛋白5（MDA5）抗體的預後因素，這是一種罕見且常伴有危及生命的快速進展性間質性肺病（RP-ILD）併發症的疾病。
研究方法：這項回顧性研究在位於台灣北部的台大醫院（一所三級醫院）進行，納入了2019年9月至2024年5月間診斷為抗MDA5抗體陽性皮肌炎的36名患者。從電子病歷中提取人口統計學、臨床和死亡率數據。使用Kaplan-Meier（K-M）生存曲線進行生存分析，並採用Cox回歸分析進行不良預後指標的回顧性分析。
研究結果：在36名抗MDA5抗體陽性皮肌炎患者中，有14名（38.9%）在研究期間死亡。死亡原因包括感染性原因（28.6%）和ILD進展（71.9%）。進一步分析顯示，死亡率與診斷時年齡較大、鐵蛋白和C反應蛋白（CRP）水平升高、N/L比率增加以及存在抗Ro52抗體呈正相關。
結論：抗MDA5抗體陽性皮肌炎患者的主要死亡原因是ILD進展（71.9%），其次是感染性原因（28.6%）。這項回顧性研究強調了診斷時年齡較大、鐵蛋白水平升高、C反應蛋白水平升高、N/L比率增加和抗Ro52抗體存在與較高死亡風險之間的關聯性。

Objective: This study aims to identify prognostic factors in dermatomyositis with anti-melanoma differentiation-associated protein 5 (MDA5) antibody, a rare condition often complicated by life-threatening, rapidly progressive interstitial lung disease (RP-ILD).
Method: Conducted at National Taiwan University Hospital, a tertiary facility in northern Taiwan, this retrospective study included 36 patients diagnosed with anti-MDA5 antibody-positive dermatomyositis between September 2019 and May 2024. Demographic, clinical, and mortality data were extracted from electronic medical records. Survival analysis was performed using Kaplan-Meier (K-M) survival curves, and Cox regression was employed for retrospective analysis of poor prognostic indicators.
Results: Among the 36 patients with dermatomyositis and anti-MDA5 antibody, 14 (38.9%) died during the study period. Causes of death included infectious causes (28.6%) and ILD progression (71.9%). Further analysis revealed a positive correlation between mortality and older age at diagnosis, elevated levels of ferritin and CRP, increased N/L ratio, and the presence of anti-Ro52.
Conclusion: Mortality in anti-MDA5 DM primarily resulted from ILD progression (71.9%), followed by infectious causes (28.6%). This retrospective study highlights the association of older age at diagnosis, elevated levels of ferritin, CRP, N/L ratio, and the presence of anti-Ro52 with increased mortality risk.