• Inclusion criteria (Aim 1):
• * Men and women between the ages of 45 and 80 years undergoing non-cardiac general or vascular surgery
• * BMI ≥30 kg/m\^2 without a previously known history of DM
• Inclusion criteria (Aim 2):
• * Men and women without known history of diabetes with ages between 45 and 80 years undergoing non-cardiac general or vascular surgery participating in Aim 1.
• * BMI ≥30 kg/m2 and pre-DM or DM by OGTT or HbA1c.
• Exclusion criteria (Aim 1):
• * Patients prescribed or taking antihyperglycemic medications
• * Patients undergoing cardiac surgery or patients anticipated to require ICU care
• * Patients expected to be admitted less than 48-72 hours after surgery
• * Severely impaired renal function (eGFR \< 30 mL/min) or clinically significant hepatic failure
• * Treatment with oral (equivalent to prednisone \> 5 mg/day) or injectable corticosteroids
• * Mental condition rendering the subject unable to understand the nature, scope, and possible consequences of the study; unable to consent
• * Pregnant or breast feeding at time of enrollment
• * Prisoners
• Exclusion criteria (Aim 2):

Exclusion Criteria:

• * Patients undergoing gastrointestinal surgery or at high risk for gastrointestinal obstruction/ileus or expected to require gastrointestinal suction
• * Patients with delayed gastric emptying, pancreatic or gallbladder disease
• * Patients with personal or family history of medullary thyroid cancer or multiple endocrine neoplasia syndrome type 2 (MEN2)