AUTHOR=Ouyang Zhi-Ming , Lin Jian-Zi , Tang Ao-Juan , Yang Ze-Hong , Yang Li-Juan , Wei Xiu-Ning , Li Qian-Hua , Liang Jin-Jian , Zheng Dong-Hui , Guo Bing-Peng , Zhao Gui , Han Qian , Dai Lie , Mo Ying-Qian 

TITLE=A Matrix Prediction Model for the 6-Month Mortality Risk in Patients With Anti-Melanoma Differentiation-Associated Protein-5-Positive Dermatomyositis

JOURNAL=Frontiers in Medicine

VOLUME=Volume 9 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/medicine/articles/10.3389/fmed.2022.860798

DOI=10.3389/fmed.2022.860798

ISSN=2296-858X

ABSTRACT=Objectives: To investigate the baseline independent risk factors for predicting 6-month mortality of anti-melanoma differentiation-associated gene 5 (anti-MDA5)-positive dermatomyositis (DM) patients and develop a matrix prediction model formed by these risk factors.
Methods: The hospitalized DM patients who completed at least 6-month follow-up were recruited as a derivation cohort. The primary exposure was defined as positive anti-MDA5 at baseline. The primary outcome was all-cause 6-month mortality after enrolment. A matrix prediction model was developed in the derivation cohort, and another published cohort was used for external validation.
Results: In derivation cohort, 82 DM patients were enrolled (mean age of onset 50±11 years and 63% female), with 40 (49%) showing positive anti-MDA5. Gottron sign/papules (OR: 5.135, 95%CI: 1.489~17.708), arthritis (OR: 5.184, 95%CI: 1.455~18.467), interstitial lung disease (ILD, OR: 7.034, 95%CI: 1.157~42.785), and higher level of C4 (OR: 1.010, 95%CI: 1.002~1.017) were independent associators with positive anti-MDA5 in DM patients. Anti-MDA5-positive DM patients had significant higher 6-month all-cause mortality than those with anti-MDA5-negative (30% vs. 0%). Among anti-MDA5-positive DM patients, compared to the survivors, non-survivors had significantly advanced age of onset (59±6 years vs. 46±9 years), higher rates of fever (75% vs. 18%), positive carcinoma embryonic antigen (CEA, 75% vs. 14%), higher level of ferritin (median 2858 ug/L vs. 619 ug/L, all p<0.05). Multivariate COX regression showed ferritin≥1250 μg/L (HR: 10.4, 95%CI: 1.8~59.9), fever (HR: 11.2, 95%CI: 2.5~49.9), and positive CEA (HR: 5.2, 95%CI: 1.0~25.7) were independent risk factors of 6-month mortality. A matrix prediction model was built to stratify anti-MDA5-positive DM patients into different subgroups with various probabilities of 6-month mortality risk. In external validation cohort, the actual 6-month all-cause mortality was 100% in extremely high-risk group, 78% in high-risk group, 43% in moderate-risk group, and 25% in low-risk group, showing good accuracy of the model.
Conclusion: Baseline characteristics of fever, positive CEA, and ferritin≥1250 μg/L are risk factors for 6-month all-cause mortality in anti-MDA5-positive DM patients. A novel matrix prediction model composed of these three clinical indicators is firstly proposed to provide a chance for exploration of individual treatment strategies in anti-MDA5-positive DM subgroups with various probabilities of mortality risk.