Metabolic Factors of Outcomes From Gastric Bypass Surgery (Cassini)

• Percent Excess Weight Loss [ Time Frame: 16 months ] [ Designated as safety issue: No ]
  Calculated as the difference between the baseline weight and weight at endpoint divided by the difference between baseline weight and ideal body weight using the medium frame range in the Metropolitan Tables for Life Insurance, 1983 x 100.
• Resting Energy Expenditure [ Time Frame: 16 months ] [ Designated as safety issue: No ]
  Energy expended at rest (minimal movement) and during fasting. Resting Energy Expenditure can be expressed per minute or per hour or per day.
• Area Under the Curve of Ghrelin and GLP-1 [ Time Frame: 16 months ] [ Designated as safety issue: No ]
  These variables will measure the combined effects of hormone concentration and duration.

• Area Under the Curve of Timed Gastrointestinal Hormones (Insulin, GIP, Pancreatic Polypeptide, Peptide YY (PYY), Amylin, Glucagon, Pro-Insulin, C-Peptide) [ Time Frame: 16 months ] [ Designated as safety issue: No ]
  These variables will measure the combined effects of hormone concentration and duration.
• Adiponectin and Lectin [ Time Frame: 16 months ] [ Designated as safety issue: No ]
  These laboratory values will be collected at Visit 3, Visit 5, Visit 6, and Visit 10.
• Subject Questionnaires [ Time Frame: 16 months ] [ Designated as safety issue: No ]
  The subscales and total scores as set out in the scoring algorithms for Food Craving Inventory-II and Questionnaire on Craving for Sweet and Rich Foods will be presented.
• Area Under the Curve of Glucose [ Time Frame: 16 months ] [ Designated as safety issue: No ]
  This variable will measure the combined effects of glucose concentration and duration.
• Hemoglobin A1c and Lipid Panel [ Time Frame: 16 months ] [ Designated as safety issue: No ]
  These laboratory values will be collected at Screening, Visit 8, and Visit 10.
• Body Mass Index [ Time Frame: 16 Months ] [ Designated as safety issue: No ]
  Will be calculated at Screening, Visit 3, Visit 5, Visit 6, Visit 8, and Visit 10.
• Percent Weight Loss [ Time Frame: 16 Months ] [ Designated as safety issue: No ]
  (Weight at Baseline - Weight at Each Visit) divided by the (Weight at Baseline).

The objective of this study is to determine whether the metabolic, endocrine and energetic response to short term caloric restriction are factors in weight loss in subjects having gastric bypass (GB) surgery.

Subjects having gastric bypass (GB) surgery within 4 months of screening visit.

Inclusion Criteria:

Subjects satisfying the following criteria will be considered the screening population and will be eligible for enrollment in this study:

1. Subject is willing to give consent and comply with evaluation and treatment schedule
2. 18 to 65 years of age (inclusive) on date of signing the ICD
3. Subject is scheduled to have non-revisional GB surgery between 2 weeks to 4 months after signing the ICD
4. Able to read, understand, and follow study procedures as outlined in the ICD.

Exclusion Criteria:

Subjects meeting the following criteria will not be eligible for enrollment:

1. Unable or unwilling to attend follow-up visits and examinations
2. Women who are pregnant, nursing at the time of screening, or planning to become pregnant within one year of the GB surgery
3. Clinically active cardiac, renal, hepatic or GI disorders

4. Screening laboratory tests with any of the following:

   • alanine aminotransferase [ALT] and/or aspartate aminotransferase [AST] ≥ 4 times upper limit of normal (ULN) according to VAMC normal ranges
   • AST:ALT > 2:1 according to VAMC normal ranges
   • Serum Creatinine ≥ 1.5 times ULN according to VAMC normal ranges
   • Blood Urea Nitrogen (BUN) ≥ 1.5 times ULN according to VAMC normal ranges
   • Positive test results for Hepatitis A, B or C

5. Clinically active thyroid or lipid disorders:

   • Thyroid-stimulating hormone (TSH) flagged as critical value (per VAMC lab normal ranges)
   • Triglycerides > 400 mg/dL

6. Anemia:

   • Mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC) outside normal VAMC range; or
   • Hematocrit < 36%
7. Uncontrolled hypertension which required a medication regimen adjustment during the 3 months prior to screening
8. Currently prescribed or taking atypical antipsychotic medication
9. Currently prescribed or taking chronic, long-term, oral corticosteroid medication
10. Diabetes requiring a drug regimen which includes insulin treatment at the time of screening
11. Unwilling or unable to refrain from having a procedure or surgery which involves the removal of skin tissue which could result in weight loss
12. Any medical condition or finding for which the PI used medical discretion to determine the subject should be excluded; or
13. Participation in any other investigational device or drug study (non survey based trial) during the course of the trial.