INS and diabetes mellitus: Data were collected according to the given parameters such as gender, age, body mass index (BMI), duration of diabetes mellitus (DM), medications (insulin, oral antihyperglycemic agents, number of tablets if used, or no medications use), presence of comorbidities, such as hypertension and dyslipidemia, HbA1c level (before surgery and at third, sixth, and 12th months after surgery), and fasting blood glucose (FBG) level (before and after surgery).