Study of Residual Insulin (C-Peptide) Secretion


About this study

The purpose of this study is to determine if you have the ability to secrete any measurable level of insulin. You will be asked to undergo a standard test called the Mixed Meal Tolerance Test (MMTT). The MMTT stimulates your body to secrete insulin. The C-peptide levels (amount of insulin that your body makes) will then be measured. A similar test was conducted when you were evaluated for enrollment into the DCCT. We want to see if that has changed some 25-30 years later.

Participation eligibility

Participant eligibility includes age, gender, type and stage of disease, and previous treatments or health concerns. Guidelines differ from study to study, and identify who can or cannot participate. There is no guarantee that every individual who qualifies and wants to participate in a trial will be enrolled. Contact the study team to discuss study eligibility and potential participation.

Inclusion Criteria:

  • Patients were asked to return if their fasting capillary glucose the morning of the test was greater than 200 mg/dL or less than 70 mg/dL.

Exclusion Criteria:

  • Participants may also be excluded for concerns of medical conditions which limit blood draws (e.g., anemia due to renal disease).

Participating Mayo Clinic locations

Study statuses change often. Please contact the study team for the most up-to-date information regarding possible participation.

Mayo Clinic Location Status

Rochester, Minn.

Mayo Clinic principal investigator

Adrian Vella, M.D.

Closed for enrollment

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