Our study found that RBP4 was an independent risk factor for coronary arteryelasticity in patients with CHD combined with T2DM and in all CHD patients, butit did not affect the coronary artery elasticity of CHD patients without T2DM.This suggests that RBP4 is important for the assessment of coronary arteryelasticity in patients with CHD combined with T2DM and that treatment targetingRBP4 may decelerate the progression of coronary artery lesions in these patients. The gene discussed is RBP4; the disease is type 2 diabetes mellitus.