Increasing the Effectiveness of the Diabetes Prevention Program

Study Overview
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Brief Summary
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The Diabetes Prevention Program (DPP) is highly effective in promoting weight loss in overweight and obese individuals (e.g., 7% average loss of body weight), and thereby reducing the risk of developing weight-related health consequences. One-on-one DPP sessions, however, are costly and the group-delivered DPP version, the Group Lifestyle Balance program (GLB), is less effective (4% average loss of body weight). The aim of this two-arm parallel randomized controlled trial is to increase the effectiveness of the GLB by integrating habit formation techniques, namely if-then plans and their mental practice, into the program. The study will provide evidence-based data on the effectiveness of an enhanced GLB intervention in promoting weight loss and in reducing weight-related risk factors for chronic health problems.

Detailed Description
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Please see brief summary.

Official Title
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Increasing the Effectiveness of the Diabetes Prevention Program Through If-then Plans and Mental Practice: A Parallel Randomized Trial

Conditions
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Overweight, Obesity

Intervention / Treatment
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* Behavioral: Enriched GLB
* Behavioral: Standard GLB


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: men and women ages of 18 and 75 overweight or obese (BMI 28-45 kg/m2) sedentary (< 200 min/week of moderate or vigorous exercise) waist circumference of >= 88cm for women and >= 102cm for men Exclusion Criteria: diabetes (hemoglobin A1c < 7.0%). taking the medication metformin (used for treating pre-diabetes or diabetes) having been pregnant in the past 6 months or planning on becoming pregnant in the next 2 years currently undergoing treatment for cancer using medication that affects body weight (e.g., loop diuretics) being unable to participate in regular moderate physical activity having severe uncontrolled hypertension (> 190/100mm Hg) being unable to communicate in English or French being diagnosed with bulimia nervosa, currently active major depression, or other severe psychiatric disease (including dementia); suffering from a heart attack, stroke, or heart failure within the past 6 months experiencing excessive weight loss (more than 10 pounds or 4.54 kilograms) in the past 3 months currently participating in another weight loss program having had bariatric surgery in the past 2 years or plans on getting it in the near future planning on moving away from Montreal within the next year having another member of one's household enrolled in the program.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Enriched GLB<br>This arm aims to increase the effectiveness of the Group Lifestyle Balance (GLB) program by integrating habit formation techniques, namely if-then plans and their mental practice, into the program. | Behavioral: Enriched GLB<br>* Habit formation techniques, namely if-then plans and their mental practice are being added to the standard Group Lifestyle Balance program.<br>* Other names: mental imagery;|
| Active Comparator: Standard GLB<br>This arm is the standard Group Lifestyle Balance (GLB) program, which is the group version of the Diabetes Prevention Program developed by the NIH. | Behavioral: Standard GLB<br>* This arm is the standard Group Lifestyle Balance program<br>* Other names: weight loss program;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Percent body weight loss | The primary outcome will be percent body weight loss from baseline to 3 months after the beginning of the intervention. Weight in kg. | 3 months after beginning of the intervention | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Percent body weight loss | Percent body weight loss 12 months after the beginning of the intervention. Weight in kg. | 12 months | 
| Percent body weight loss | Percent body weight loss 24 months after the beginning of the intervention. Weight in kg. | 24 months | 
| Personal weight loss goal | Reaching percent body weight loss goal (7% of body weight) from baseline to 3 months after the beginning of the intervention. Weight in kg. | 3 months | 
| Personal weight loss goal | Reaching percent body weight loss goal (7% of body weight) 12 months after the beginning of the intervention. Weight in kg. | 12 months | 
| Personal weight loss goal | Reaching percent body weight loss goal (7% of body weight) 24 months after the beginning of the intervention. Weight in kg. | 24 months | 
| Personal exercise goal | Reaching exercise goal (150 min/week) from baseline to 3 months after the beginning of the intervention. Sum of minutes over 7 days. | 3 months | 
| Personal exercise goal | Reaching exercise goal (150 min/week) 12 months after the beginning of the intervention. Sum of minutes over 7 days. | 12 months | 
| Personal exercise goal | Reaching exercise goal (150 min/week) 24 months after the beginning of the intervention. Sum of minutes over 7 days. | 24 months | 
| Waist circumference | Risk factor for chronic health problems. | 3 months | 
| Waist circumference | Risk factor for chronic health problems. | 12 months | 
| Waist circumference | Risk factor for chronic health problems. | 24 months | 
| Hemoglobin A1c levels | Risk factor for chronic health problems. | 3 months | 
| Hemoglobin A1c levels | Risk factor for chronic health problems. | 12 months | 
| Hemoglobin A1c levels | Risk factor for chronic health problems. | 24 months | 
| Blood pressure | Risk factor for chronic health problems. | 3 months | 
| Blood pressure | Risk factor for chronic health problems. | 12 months | 
| Blood pressure | Risk factor for chronic health problems. | 24 months | 
| Total cholesterol/HDL ratio | Risk factor for chronic health problems. | 3 months | 
| Total cholesterol/HDL ratio | Risk factor for chronic health problems. | 12 months | 
| Total cholesterol/HDL ratio | Risk factor for chronic health problems. | 24 months | 
| Physical activity duration | Total minutes per week. | 3 months | 
| Physical activity duration | Total minutes per week. | 12 months | 
| Physical activity duration | Total minutes per week. | 24 months | 
| Number of steps taken per week | Steps taken per week, recorded using a pedometer. | 3 months | 
| Number of steps taken per week | Steps taken per week, recorded using a pedometer. | 12 months | 
| Number of steps taken per week | Steps taken per week, recorded using a pedometer. | 24 months | 
| Exercise stress test (EST) |  | 3 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Group-delivered Diabetes Prevention Program, Obesity, Overweight, Lifestyle change, Healthy eating, Weight loss, Exercise, Cognitive-behavioral intervention, Implementation intentions, Mental imagery, Mental practice, If-then plans