摘要目的:根据生存结局探究影响抗黑色素瘤分化相关基因5抗体（MDA5）抗体DM（MDA5-DM）患者预后的临床因素。方法:连续入选126例MDA5-DM患者，根据随访结局分为死亡组和生存组，收集患者临床资料，比较2组间的生存时间、实验室指标、临床症状、肺功能、肌炎抗体谱、治疗方案等。另外，使用酶联免疫吸附试验（ELISA）法测定MDA5-DM患者和健康对照者血清中IL-15、高迁移率族蛋白1（HMGB1）、可溶性CD163（sCD163）的水平。计量资料采用独立样本 t检验或Mann-Whitney U非参数检验比较2组间差异，计数资料采用 χ2检验或Fisher确切概率法。使用Cox比例风险回归模型分析与预后有关的临床因素，Kaplan-Meier法绘制生存曲线，Log-rank检验比较组间生存率差异。 结果:Cox多因素回归分析显示年龄>57岁[ HR（95% CI）=3.05（1.20，7.80）， P=0.020]、快速进展型ILD（RP-ILD）[ HR（95% CI）=25.07（5.42，115.98）， P<0.001]、抗Ro52抗体水平[ HR（95% CI）=3.41（1.36，8.53）， P=0.009]是MDA5-DM患者预后不良的独立危险因素。ELISA结果分析显示血清IL-15[0.91（0.66，2.00）pg/ml与0.51（0.39，0.72）pg/ml， Z=-4.57， P<0.001]和HMGB1[230.53（90.40，394.31）ng/ml与32.66（17.82，46.21）ng/ml， Z=-6.52， P<0.001]水平在MDA5-DM患者中较健康对照者显著升高，而在死亡组及生存组中IL-15[1.21（0.63，2.12）pg/ml与0.91（0.68，1.66）pg/ml， Z=-0.30， P=0.766]、HMGB1[267.61（167.03，444.23）ng/ml与228.35（74.74，344.32）ng/ml， Z=0.82， P=0.413]及sCD163[112.70（93.45，148.51）ng/ml与132.72（96.79，203.18）ng/ml， Z=-0.62， P=0.536]的水平差异均无统计学意义。 结论:高龄、合并RP-ILD以及高水平的抗Ro52抗体分别显著增加了MDA5-DM患者的死亡风险，对存在上述因素的患者在疾病早期进行强化随访可能有助于改善预后。

abstractsObjective:To explore clinical factors of poor prognosis in patients with anti-melanoma differentiation-associated gene 5 andtibody positive dermatomyositis (MDA5-DM).Methods:One hundred and twenty-six enrolled adults with MDA5-DM were divided into the survival group and the deceased group according to the outcomes. Survival time, clinical manifestations, laboratory tests, pulmonary function tests, myositis antibodies and treatments were collected for statistical analysis. Serum concentrations of IL-15, HMGB1, and sCD163 were measured by ELISA in MDA5-DM patients and healthy controls. Mann-Whitney U nonparametric test and Student′s t-test were used to compare the continuous variables between the two groups, and χ2 or Fisher′s exact test were used for comparison of categorical variables. Cox regression analysis was used to assess the survival predictors in MDA5-DM patients. The cumulative survival rate was calculated by Kaplan-Meier curve analysis, and Log-rank tests were used to examine differences in survival curves. P<0.05 was considered statistically significant. Results:Cox multivariate regression analysis revealed that age > 57 years [ HR (95% CI)=3.05 (1.20, 7.80), P=0.020], RP-ILD [ HR (95% CI)=25.07 (5.42, 115.98), P<0.001], and levels of anti-Ro52 antibody [ HR (95% CI)=3.41 (1.36, 8.53), P=0.009] were important prognostic factors independent of multiple clinical parameters. The ELISA test results showed that the levels of serum IL-15[0.91 (0.66, 2.00)pg/ml vs. 0.51(0.39, 0.72)pg/ml, Z=-4.57, P<0.001] and HMGB1 [230.53(90.40, 394.31)ng/ml vs. 32.66 (17.82, 46.21)ng/ml, Z=-6.52, P<0.001] in MDA5-DM patients were significantly higher than those in healthy controls, but there were no significant differences in the level of serum IL-15 [1.21(0.63, 2.12)pg/ml vs. 0.91(0.68, 1.66)pg/ml, Z=-0.30, P=0.766], HMGB1[267.61(167.03, 444.23)ng/ml vs. 228.35(74.74, 344.32)ng/ml, Z=0.82, P=0.413], and sCD163 [112.70(93.45, 148.51)ng/ml vs. 132.72(96.79, 203.18)ng/ml, Z=-0.62, P=0.536] between the survival group and the deceased group. Conclusion:Older age, RP-ILD, and high levels of anti-Ro52 antibody significantly increase the risk of death in MDA5-DM patients. Intensive follow-up of patients with the above factors in the early stages may help to improve the prognosis.