Prognostic analysis of MDA5‐associated clinically amyopathic dermatomyositis with interstitial lung disease

Abstract

Abstract Objective To investigate the prognostic factors of patients with anti‐melanoma differentiation‐associated gene 5 (MDA5) positive clinically amyopathic dermatomyositis (CADM) and interstitial lung disease (ILD). Methods A retrospective analysis was conducted on clinical data of 125 patients with anti‐MDA5 + CADM‐ILD collected from 10 branches in eastern China between December 2014 and December 2022. Prognostic factors were analyzed using χ2 test, Log‐rank test, COX and logistic regression analysis. Results In this cohort, 125 anti‐MDA5 + CADM‐ILD patients exhibited a rapidly progressive interstitial lung disease (RPILD) incidence of 37.6%, and an overall mortality rate of 24.8%. One patient was lost to follow‐up. After diagnosis of RPILD, a mortality rate of 53.2% occurred in patients died within 3 months, and that of 5.6% appeared in those who survived for more than 3 months. Multiple factor analysis revealed that C‐reactive protein (CRP) ≥ 10 mg/L (p = 0.01) and recombinant human tripartite motif containing 21 (Ro52) (+) (p = 0.003) were associated with a higher risk of RPILD in anti‐MDA5 + CADM‐ILD patients; CRP ≥ 10 mg/L (p = 0.018) and the presence of RPILD (p = 0.003) were identified as the factors influencing survival time in these patients, while arthritis was the protective factor (p = 0.016). Conclusion Patients with anti‐MDA5 + CADM‐ILD will have a higher mortality rate, and the initial 3 months after diagnosis of RPILD is considered the risk window for the dismal prognosis. Patients with CRP ≥ 10 mg/L, Ro52 (+) and RPILD may be related to a shorter survival time, while patients complicated with arthritis may present with relatively mild conditions.

Keywords

• anti–melanoma differentiation–associated gene 5
• clinically amyopathic dermatomyositis
• interstitial lung disease
• prognosis