Meanwhile, in the previous study, the serum ghrelin correlated inversely with the fasting blood glucose, HgbA1c, and urine albumin-to-creatinine ratio, but exhibited a positive correlation with HDL only in the middle-aged (41–64 years) and old (65–76 years) subjects with newly diagnosed T2DM and normal glucose tolerance [44]. Here, GHRL is linked to type 2 diabetes mellitus.