PCSK9 and idiopathic pulmonary fibrosis: The IVW-MR analysis showed that the reduced LDL-C level by inhibitors or enhancements of NPC1L1, PCSK9, ABCG5, and ABCG8 increased IPF risk (OR = 2.74, 95% CI: 1.05 – 7.12, P = 0.039; OR = 1.36, 95% CI: 1.02 – 1.82, P = 0.037; OR = 1.66, 95% CI: 1.12 – 2.48, P = 0.011; OR = 1.68, 95% CI: 1.14 – 2.48, P = 0.009).