Risk And Prognostic Factors Of Anti-MDA5 Antibody Positive Dermatomyositis

Objective:To analyze the clinical characteristics of anti-MDA5 antibody positive dermatomyositis(MDA5+DM),and to explore the risk factors and prognostic factors of anti-MDA5 antibody positive dermatomyositis.Methods:Patients with MDA5+DM admitted to the First Affiliated Hospital of Zhengzhou University from November 2018 to November 2019 were selected as the study subjects,MDA5-DM patients admitted to the First Affiliated Hospital of Zhengzhou University during this period were selected as the control group,the clinical manifestations and laboratory indicators of the two groups were compared.The risk and prognostic factors of DM with anti-MDA5 antibody positive were determined by Logistic and Cox analysis,and Kaplan-Meier method was used to draw the survival curve.Results:Of 144 enrolled patients,60 were classified as MDA5+DM(44 cases survived,16 cases died)and 84 as MDA5-DM(75 cases survived,9 cases died).MDA5+DM had significantly more clinical symptoms including periorbital rash,Shawl sign,Gottron’s sign and interstitial lung disease(ILD)and higher mortality than MDA5-DM(P<0.05).The survival time was significantly shortened,erythrocyte sedimentation rate(ESR),Krebs von den lungen-6(KL-6)levels were significantly increased,and creatine kinase(CK)levels were significantly lower(P<0.05).Logistics multivariate analysis showed that Gottron sign was an independent risk factor for MDA5+DM,with OR value of 8.248.In MDA5+DM patients,Kaplan-Meier method showed that the cumulative survival rates of MDA5+DM at 1,3,6 and 12 months were 93%,88%,83%and 77%,respectively.Log-rank results showed that the survival probability was significantly reduced in older patients(>50 years old)(P<0.001),patients without immunosuppressive agents(P<0.001),and patients with elevated KL-6(P=0.009).Cox multivariate analysis showed age(HR=1.010;P=0.004)and KL-6 levels(HR=1001;P=0.012)was an independent risk factor for death of MDA5+DM;Immunosuppressive agents were used(HR=0.074;P<0.001)was an independent protective factor.Conclusion:Gottron sign is closely related to anti-MDA5 antibody positive dermatomyositis.The survival rate of anti-MDA5 antibody positive dermatomyositis was low,and the KL-6 level was positively correlated with the risk of death.It is suggested that anti-MDA5 antibody screening and KL-6 level monitoring should be paid attention to in the clinical diagnosis and treatment of patients with the above clinical characteristics,which is helpful to improve the detection rate and survival rate of anti-MDA5 antibody positive dermatomyositis patients.