Prognostic value of automated assessment of interstitial lung disease on CT in systemic sclerosis

• Published in: Rheumatology (Oxford, England) Vol. 63; no. 1; pp. 103 - 110
• Main Authors: Le Gall, Aëlle, Hoang-Thi, Trieu-Nghi, Porcher, Raphaël, Dunogué, Bertrand, Berezné, Alice, Guillevin, Loïc, Le Guern, Véronique, Cohen, Pascal, Chaigne, Benjamin, London, Jonathan, Groh, Matthieu, Paule, Romain, Chassagnon, Guillaume, Vakalopoulou, Maria, Dinh-Xuan, Anh-Tuan, Revel, Marie Pierre, Mouthon, Luc, Régent, Alexis
• Format: Journal Article
• Language: English
• Published: England 04.01.2024
• Subjects: high-resolution CT; SSc; interstitial lung disease; prognosis; artificial intelligence
• ISSN: 1462-0324; 1462-0332; 1462-0332
• DOI: 10.1093/rheumatology/kead164

Stratifying the risk of death in SSc-related interstitial lung disease (SSc-ILD) is a challenging issue. The extent of lung fibrosis on high-resolution CT (HRCT) is often assessed by a visual semiquantitative method that lacks reliability. We aimed to assess the potential prognostic value of a deep-learning-based algorithm enabling automated quantification of ILD on HRCT in patients with SSc. We correlated the extent of ILD with the occurrence of death during follow-up, and evaluated the additional value of ILD extent in predicting death based on a prognostic model including well-known risk factors in SSc. We included 318 patients with SSc, among whom 196 had ILD; the median follow-up was 94 months (interquartile range 73-111). The mortality rate was 1.6% at 2 years and 26.3% at 10 years. For each 1% increase in the baseline ILD extent (up to 30% of the lung), the risk of death at 10 years was increased by 4% (hazard ratio 1.04, 95% CI 1.01, 1.07, P = 0.004). We constructed a risk prediction model that showed good discrimination for 10-year mortality (c index 0.789). Adding the automated quantification of ILD significantly improved the model for 10-year survival prediction (P = 0.007). Its discrimination was only marginally improved, but it improved prediction of 2-year mortality (difference in time-dependent area under the curve 0.043, 95% CI 0.002, 0.084, P = 0.040). The deep-learning-based, computer-aided quantification of ILD extent on HRCT provides an effective tool for risk stratification in SSc. It might help identify patients at short-term risk of death.