FGF21 and diabetes mellitus: In cross-sectional studies on DM patients, values of seral FGF-21 were relatively high and positively correlated with high intima-media thickness of carotid arteries [26] and subclinical atherosclerosis, which is defined as an intima-media thickness of >1.0 mm or plaque of the carotid, femoral, or iliac arteries [28].