APOB and coronary stenosis: The fitting results showed that staying up late, HDL-C, and LDL-C/ApoB were the independent factors affecting the severity of coronary artery stenosis in the young group (P < 0.05), and the risk of severe stenosis or complete occlusion was lower in young AMI patients without staying up late and abnormalities of HDL-C and LDL-C/ApoB (P < 0.05, Table 8).