Moreover, our study yielded robust null results for circulating inflammatory cytokines (IL-1ra, IL-2ra, IL-2, IL-6, IL-8, IL-10, IL-18, MIP1a, MIP1b, MCP1, RANTES, TANLN, and CXCL9), indicating that prolonged exposure to elevated levels of these circulating inflammatory cytokines does not increase the risk of IPF. This evidence concerns the gene CXCL9 and idiopathic pulmonary fibrosis.