Long-acting Exenatide and Cognitive Decline in Dysglycemic Patients

Inclusion Criteria: * patients capable of giving informed consent * dysglycemia/prediabetes defined as fasting plasma glucose between 100 and 125 mg/dl and/or 2-hour plasma glucose between 140 and 199 mg/dl after a 75 g OGTT and/or a HbA1c value between 5.7 and 6.4% * diagnosis of MCI according to the Petersen clinical criteria (the expected corrected scores at the MMSE are from 24 to 27) * age \>50\<80 yrs * stable medication for the past 3 months * Caucasian ethnicity Exclusion Criteria: * age \<50\>80 yrs * incapability to give informed consent * diabetes defined according to American Diabetes Association (ADA) criteria * clinically significant liver or kidney dysfunction defined as s-ALT \> 2 times upper reference or estimated creatinine-clearance (eGFR) \< 60 mL / min/1.73m2, assessed by with CKD-EPI formula * endocrinological diseases other than well controlled hypothyroidism, personal or family history of medullary thyroid carcinoma or Multiple Endocrine Neoplasia (MEN) syndrome, severe gastro-intestinal diseases (i.e gastroparesis, dumping syndromes), current or history of chronic or acute pancreatitis * any contraindication to the use of exenatide as per the Summary of Product Characteristics * known abuse of alcohol or drugs * ferro-magnetic prosthesis, pacemaker or other metals incorporated in the body * significant neurologic disease other than MCI (i.e. Parkinson's disease, multiple system atrophy, normal pressure hydrocephalus, progressive supranuclear palsy, subarachnoid hemorrhage, brain neoplasms, Huntington disease, epilepsy or head trauma) * BMI ≤22 Kg/m2 in subject ≥ 70 yrs * MRI/CT showing unambiguous etiological evidence of cerebrovascular disease with regard to MCI * severe sensory defects; current presence of clinically significant psychiatric disorder * warfarin treatment, clinically significant systemic condition * history of cancer within the last 5 yrs * known allergy to exenatide or any of the other components.