CT-derived Biomarkers as Predictors of Overall Survival in Patients with Idiopathic Pulmonary Fibrosis

Idiopathic pulmonary fibrosis (IPF) is a fatal disease, with a median survival time of 2.5 years if left untreated. Further, the lack of established biomarkers for assessing mortality risk remains a significant challenge. Body composition analysis (BCA) has recently gained prominence as a predictive tool across various medical conditions. This study investigated the potential correlation between fully automated BCA-derived markers and overall survival (OS) in a cohort of IPF patients. A retrospective analysis was conducted on 79 IPF patients (comprising 19% females) who had undergone thoracic CT scans, with 38% performed at the time of diagnosis. Employing a 3D Multi-res U-Net, a fully automated BCA was conducted, and its resulting features were amalgamated to form Sarcopenia, Fat, and Myosteatosis indices. For comparative analysis, the patient cohort was dichotomized into those who succumbed within two years (n=36) and those who did not (n=33). The median survival time for entire cohort was 23 months. Out of 79 patients, 67% of patients died, with 45% within the initial two years.

Interestingly, elevated Sarcopenia and Fat indices, as well as lower Myosteatosis indices (< median values), were associated with prolonged survival times (e.g., 35 vs 16 months for high vs. low Sarcopenia index, p=0.0658; 44 vs. 14 months for high vs. low Fat index, p < 0.0001; 33 vs. 14 months for low vs. high Myosteatosis index, p=0.0056). Notably, among these BCA-derived indices, only the Fat index emerged as an independent predictor of survival (HR=0.394, 95%-CI=0.205-0.758, p=0.005) compared to other clinical parameters. In conclusion, fully automated BCA is promising in furnishing valuable biomarkers with predictive potential for overall survival in individuals afflicted with IPF.

Poster ID 1131, European Respiratory Society (ERS) International Congress 2023, Milan, Italy, 9-13 September 2023

Predicting Factors of Acute Exacerbation of Idiopathic Pulmonary Fibrosis

In the context of idiopathic pulmonary fibrosis (IPF), a debilitating interstitial lung disease characterized by a notably grim prognosis and distinctive radiological and histological features resembling usual interstitial pneumonia, there exists a grave complication known as acute exacerbation of IPF (AE-IPF), marked by an exceedingly poor outlook. The primary aim of this study was to delineate predictive and prognostic factors associated with AE-IPF. Methodologically, we conducted a retrospective analysis encompassing patients afflicted with IPF under Rennes University Hospital's care and four local public hospitals. Our investigation delved into the incidence and outcomes of AE-IPF, employing univariate and multivariate analyses to discern independent variables linked to this severe complication. Among the 307 patients included in our study, a substantial subset, comprising 81 individuals (26.4%), developed AE-IPF within a median timeframe of 2.2 ± 2.0 years following their IPF diagnosis. Factors independently associated with the occurrence of AE-IPF encompassed a diminished forced vital capacity (FVC) with a hazard ratio (HR) of 0.94, as well as elevated blood neutrophil and lymphocyte counts at the time of IPF diagnosis, with respective HRs of 1.01 and 1.13.

Furthermore, our findings revealed that individuals who experienced AE-IPF had a markedly shorter median survival of 5.39 months, in contrast to those without AE-IPF. Notably, the median survival was 2.84 years versus 4.33 years in this comparison. In conclusion, our study identified lower FVC and elevated blood neutrophil and lymphocyte counts at IPF diagnosis as risk factors for AE-IPF.