Investigation Into the Effects of Blood Glucose Levels Upon Eating Behavior in Lean and Obese Non-diabetic and Diabetic Subjects

Study Overview
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Brief Summary
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To investigate whether the daily glucose profiles as assessed by continuous glucose monitoring for 1 week of normal weight and obese individuals relate to hunger levels and food intake.

Detailed Description
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To evaluate the effect of blood glucose levels on eating behavior in a population of patients with diabetes in a free-living environment; the investigators plan to study lean healthy control subjects (BMI <25 kg/m2) and obese non-diabetic subjects (BMI > 30 kg/m2). The participants who qualify will be invited to use the CGMS (DEXCOM G4 Platinum) for up to 7 days. On the visit for placement of the CGMS: 1) the participants will be explained by one of the study physicians how to use a glucometer (FreeStyle or Accu-Check), 2) they will have the CGMS inserted under the skin, and 3) they will be instructed how to fill up the food log (informational brochures are available at the end of the protocol. On the second visit (up to 7 days after the initial visit) the CGMS will be removed from the skin and the glucose meter and food log will be returned to the investigators. When this study was initially designed, it incorporated 2 additional arms in the study: T1DM and obese T2DM patients. These patients were never recruited for the study.

Official Title
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Investigation Into the Effects of Blood Glucose Levels Upon Eating Behavior in Lean and Obese Non-diabetic and Diabetic Subjects

Conditions
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Diabetes

Intervention / Treatment
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* Device: Continuous Glucose Monitoring System (CGMS)
* Behavioral: Food log


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: A1c < 10.5 % Exclusion Criteria: BMI <18 (no upper limit), Creatinine > 1.5 mg/dL, Hgb < 10 mg/dL, ALT > 2.5 X ULN, untreated thyroid disease, uncontrolled hypertension, known neurological disorders, untreated psychiatric disorders, use of antidepressants and psychiatric medications, use of weight loss medications in the 6 months prior to the study, malignancy, smoking, current or recent steroid use in last 3 months, history of current illicit drug use; for women: pregnancy, or breastfeeding.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Lean Healthy Control<br>(BMI <25 kg/m2) | Device: Continuous Glucose Monitoring System (CGMS)<br>* The CGMS consists of 3 parts: sensor, transmitter and monitor. The small sensor measures the glucose levels from the interstitial tissue. The transmitter is attached on top of the sensor and connects wirelessly to the monitor. The sensor is sterile and comes in an unopened package. It has a plastic wire-like tip that is placed under the skin and continuously measures the glucose levels. One of the study physicians will insert the CGMS wire-like tip under the volunteer's skin with the use of the DEXCOM sensor insertion kit. The transmitter is snapped to the sensor pod and the sensor/transmitter unit will be attached to the skin with an adhesive patch. The monitor is the size of a small hand-held device with a digital screen that displays a graph showing the glucose levels from the previous 4-24 hours.<br>* Other names: DEXCOM G4 Platinum;Behavioral: Food log<br>* The Food Record will ask about amount and type of food consumed throughout the day. The participants will also register how hungry they are before the meal and how full they feel after they ate, and type and duration of physical activity<br>|
| Active Comparator: Obese non-diabetic subject<br>BMI > 30 kg/m2 | Device: Continuous Glucose Monitoring System (CGMS)<br>* The CGMS consists of 3 parts: sensor, transmitter and monitor. The small sensor measures the glucose levels from the interstitial tissue. The transmitter is attached on top of the sensor and connects wirelessly to the monitor. The sensor is sterile and comes in an unopened package. It has a plastic wire-like tip that is placed under the skin and continuously measures the glucose levels. One of the study physicians will insert the CGMS wire-like tip under the volunteer's skin with the use of the DEXCOM sensor insertion kit. The transmitter is snapped to the sensor pod and the sensor/transmitter unit will be attached to the skin with an adhesive patch. The monitor is the size of a small hand-held device with a digital screen that displays a graph showing the glucose levels from the previous 4-24 hours.<br>* Other names: DEXCOM G4 Platinum;Behavioral: Food log<br>* The Food Record will ask about amount and type of food consumed throughout the day. The participants will also register how hungry they are before the meal and how full they feel after they ate, and type and duration of physical activity<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Rate of Changing Glucose Level | The CGM sensor measures the glucose levels from the interstitial tissue. Presented is the rate of changing glucose level (mg/dl/min). | 3-5 days | 
| Glucose Peak | The CGM sensor measures the glucose levels from the interstitial tissue. Presented is the glucose peak (mg/dl). | 3-5 days | 
| Glucose Nadir | The CGM sensor measures the glucose levels from the interstitial tissue. Presented is the glucose nadir (mg/dl). | 3-5 days | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Difference in Glucose Peak and Nadir | The CGM sensor measures the glucose levels from the interstitial tissue. Presented is the difference in glucose peak and nadir (mg/dl). | 3-5 days | 
| Average Daily Hunger Rating | Average daily hunger was measured using a self-report scale. Hunger is measured on a scale from 1-10. 10 is the most hungry, 1 is the least hungry. | 3-5 days | 
| Nutirion Intake: Energy | Data were collected through food journals. Energy and macronutrient composition were calculated from self-reported food records based on Nutrition Data System for Research (NDS-R). Presented is the average daily energy intake (kcal/day). | 3-5 days | 
| Nutirion Intake: Carbohydrate | Data were collected through food journals. Energy and macronutrient composition were calculated from self-reported food records based on Nutrition Data System for Research (NDS-R). Presented is the average daily carbohydrate intake (g/day). | 3-5 days | 
| Nutirion Intake: Fat | Data were collected through food journals. Energy and macronutrient composition were calculated from self-reported food records based on Nutrition Data System for Research (NDS-R). Presented is the average daily fat intake (g/day). | 3-5 days | 
| Nutirion Intake: Protein | Data were collected through food journals. Energy and macronutrient composition were calculated from self-reported food records based on Nutrition Data System for Research (NDS-R). Presented is the average daily protein intake (g/day). | 3-5 days | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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glucose monitoring, hunger levels, food intake