After adjusted for age and gender, diabetes (OR = 2.550, 95%CI: 1.733–3.751, P < 0.001), TG (OR = 1.340, 95%CI: 1.109–1.620, P = 0.002), HDL-C (OR = 0.214, 95%CI: 0.096–0.474, P < 0.001), FBG (OR = 1.152, 95%CI: 1.061–1.251, P = 0.0013), IL-4 (OR = 0.747, 95%CI: 0.605–0.923, P = 0.007), IL-12p70 (OR = 0.566, 95%CI: 0.464–0.691, P < 0.001), IL-17 (OR = 0.913, 95%CI: 0.876–0.952, P < 0.001) and IFN-α (OR = 0.837, 95%CI: 0.746–0.939, P = 0.002) were still correlated with severe CAD. This evidence concerns the gene IL4 and diabetes mellitus.