Clinical Trials

Inclusion Criteria:

• Obese group with IFG

  • Aged between 25 and 70 years of age

  • BMI > 28 Kg/M² and < 40 Kg/M²

  • Impaired Fasting Glucose (IFG – fasting glucose >100 but <126 mg/dL)

  • Reside within a 100-mile radius of Mayo Clinic, Rochester, MN

• Control group (Lean)

  • BMI > 19 Kg/M² and < 25 Kg/M²

  • Fasting glucose < 100mg/dL

  • Reside within a 100-mile radius of Mayo Clinic, Rochester, MN

• T1DM group

  • BMI > 28 Kg/M² and < 40 Kg/M²

  • Type 1 diabetes (T1DM)

  • Reside within a 100-mile radius of Mayo Clinic, Rochester, MN

• Obese group with NFG

  • BMI > 28 Kg/M² and < 40 Kg/M²

  • Fasting glucose < 100mg/dL

  • Reside within a 100-mile radius of Mayo Clinic, Rochester, MM

Exclusion Criteria:

• Obese group with IFG

  • Age < 25 (to ensure that we are not studying subjects with latent type 1 diabetes as people in Olmsted County presenting before age 25 have a high incidence of T1DM) or > 70 years (to avoid extreme age as a factor in islet function)

  • BMI < 28 Kg/M² or > 40 Kg/M²

  • HbA_1c > 6.5% or fasting glucose < 100mg/dL or > 126 mg/dL

  • Use of any glucose-lowering agents

  • For female subjects: positive pregnancy test at the time of enrollment or study

  • History of prior upper abdominal surgery such as adjustable gastric banding, pyloroplasty and vagotomy

  • Active systemic illness or malignancy

  • Symptomatic macrovascular or microvascular disease

• Control group (Lean)

  • Age < 25 or > 70 years (to enable matching to the Obese group with IFG)

  • BMI < 19 Kg/M² or > 25 Kg/M²

  • HbA_1c > 5.8% or fasting glucose > 100mg/dL.

  • (Use of any glucose-lowering agents

  • For female subjects: positive pregnancy test at the time of enrollment or study

  • History of prior upper abdominal surgery such as adjustable gastric banding, pyloroplasty and vagotomy

  • Active systemic illness or malignancy

  • Symptomatic macrovascular or microvascular disease

• T1DM group

  • Age < 25 or > 70 years (to enable matching to the Obese group with IFG)

  • BMI < 28 Kg/M² or > 40 Kg/M² (to enable matching to the Obese group with IFG)

  • HbA_1c < 5.8 or > 9.0%

  • Use of any glucose-lowering agents beyond insulin

  • For female subjects: positive pregnancy test at the time of enrollment or study

  • History of prior upper abdominal surgery such as adjustable gastric banding, pyloroplasty and vagotomy

  • Active systemic illness or malignancy

  • Symptomatic macrovascular or microvascular disease

• Obese group with NFG

  • Age < 25 or > 70 years (to enable matching to the Obese group with IFG)

  • BMI < 28 Kg/M² or > 40 Kg/M² (to enable matching to the Obese group with IFG)

  • HbA_1c > 5.8% or fasting glucose > 100mg/dL

  • Use of any glucose-lowering agents

  • For female subjects: positive pregnancy test at the time of enrollment or study

  • History of prior upper abdominal surgery such as adjustable gastric banding, pyloroplasty and vagotomy

  • Active systemic illness or malignancy

  • Symptomatic macrovascular or microvascular disease

Note: Other protocol defined Inclusion/Exclusion Criteria may apply.

Eligibility last updated 07/21/2026. Questions regarding updates should be directed to the study team contact.