A Study to Evaluate the Effect of Metformin on Brain Function in Insulin-resistant Elderly People


About this study

The purpose of this study is to determine whether 40 weeks of metformin administration in elderly people (> 60 years) with insulin resistance enhances brain mitochondrial ATP production, to determine the effect of 40 weeks of metformin administration in elderly people (> 60 years) with insulin resistance on blood flow and functional network in different areas of brain, and to determine the effect of 40 weeks of metformin administration in elderly people (> 60 years) with insulin resistance on cognitive function.

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: 

To be eligible for the study, a subject must be willing to be randomized and be retained in the study for its duration and meet the following criteria:

  • Age ≥ 60 years.
  • BMI ≥ 25 kg/m^2.
  • Fasting glucose ≥ 100-140 mg/dL.
  • Non-smoker.
  • English language proficiency.

Exclusion Criteria:

The presence of any of the following is an exclusion for the study:

  • Active coronary artery disease or heart failure.
  • A known medical condition that in the judgment of the investigator might interfere with the completion of the protocol such as the following examples:
    • Inpatient psychiatric treatment in the past 6 months;
    • Presence of a known and active adrenal disorder;
    • Abnormal liver function test results (Transaminase > 2 times the upper limit of normal); testing required for subjects taking medications known to affect liver function or with diseases known to affect liver function;
    • Abnormal renal function test results (calculated GFR < 60 mL/min/1.73m^2); testing required for subjects with diabetes duration of greater than 5 years post onset of puberty;
    • Active gastroparesis;
    • If on antihypertensive, thyroid, anti-depressant or lipid lowering medication, lack of stability on the medication for the past 2 months prior to enrollment in the study;
    • Uncontrolled thyroid disease (TSH undetectable or > 10 mlU/L); testing required within three months prior to admission for subjects with a goiter, positive antibodies, or who are on thyroid hormone replacement, and within one year otherwise;
    • Abuse of alcohol or recreational drugs;
    • Infectious process not anticipated to resolve prior to study procedures (e.g., meningitis, pneumonia, osteomyelitis);
    • Uncontrolled arterial hypertension (resting diastolic blood pressure > 90 mmHg and/or systolic blood pressure >160 mmHg) at the time of screening;
    • Oral steroids;
    • A recent injury to body or limb, muscular disorder, use of any medication, any carcinogenic disease, or other significant medical disorder if that injury, medication or disease in the judgment of the investigator will affect the completion of the protocol;
    • Any metal in the body that could interfere with magnetic resonance imaging (MRI) including pacemaker or implanted defibrillator, neurostimulators, ear implants, metal fragments within the body, metal joints, rods, pins, plates or screws.
  • Subjects without English proficiency.


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 Contact

Rochester, Minn.

Mayo Clinic principal investigator

K Nair, M.D., Ph.D.

Open for enrollment

Contact information:

Frederick De Ruiter B.S.



More information


Publications are currently not available

Study Results Summary

Not yet available

Supplemental Study Information

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