1 Division of Endocrinology and Metabolic Disease, Department of Advanced Medical and Surgical Sciences, Università L. Vanvitelli, Naples, Italy. Electronic address: dario.giugliano@unicampania.it.
2 Diabetes Unit, Department of Advanced Medical and Surgical Sciences, Università L. Vanvitelli, Naples, Italy.
3 Division of Endocrinology and Metabolic Disease, Department of Advanced Medical and Surgical Sciences, Università L. Vanvitelli, Naples, Italy.