Subgroup analysis revealed that the COL1A1 expression above this cut-off was associated with 2.2 times increased risk of death in the non-IPF ILD cohort (HR 2.2; CI 1-4.8, p=0.04) but not in IPF (HR 1.55; CI 0.7-3.2, p=NS). This evidence concerns the gene COL1A1 and idiopathic pulmonary fibrosis.