Predicting Survival Across Acute Exacerbation of Interstitial Lung Disease in Patients with Idiopathic Inflammatory Myositis: The GAP-ILD Model.

Abstract

IntroductionRisk prediction is challenging in patients with idiopathic inflammatory myopathies (IIM) and acute exacerbation of interstitial lung disease (AE-ILD) because of heterogeneity and patient-specific variables. Our objective was to assess whether mortality is accurately predicted in patients with IIM and AE-ILD by using the gender age physiology ILD (GAP-ILD) model, a clinical prediction model that was previously validated in patients with idiopathic pulmonary fibrosis.MethodsA retrospective cohort study was conducted in the First Affiliated Hospital, Zhejiang University, wherein 60 consecutive patients with IIM and AE-ILD admitted between February 2011 and April 2019. The GAP-ILD was assessed retrospectively on the basis of gender, age and pulmonary function test.ResultsPatients with AE-ILD (n = 60) were identified and collected, 26 deaths occurred during follow-up, and the non-survivors group presented a higher level of GAP-ILD index (P = 0.005), bacterial infection (P = 0.013), and myositis disease activity assessment (MYOACT) (P = 0.031). The subsequent multivariate logistic regression analysis of overall mortality in AE-ILD revealed that bacterial infection (OR 5.275, P = 0.037) and GAP-ILD index (OR 2.292, P = 0.011) conferred significant risk of mortality. The GAP-ILD index was able to separate patients with AE-ILD into two groups with a statistically significant difference in survival rate (log rank P = 0.002). Satisfactory mortality estimation was maintained in the corresponding GAP-ILD index across the AE-ILD group.ConclusionThe GAP-ILD model preforms well in risk prediction of mortality among patients with IIM and AE-ILD. Pulmonary bacterial infection can also be taken as an initial predictor of poor prognosis in patients with IIM and AE-ILD that must be taken seriously.Electronic Supplementary MaterialThe online version of this article (10.1007/s40744-020-00244-1) contains supplementary material, which is available to authorized users.