The Lifestyle Education About Prediabetes (Leap) Study

Study Overview
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Brief Summary
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This research will test whether a standard version or very low-carbohydrate version of the Diabetes Prevention Program better improves outcomes like blood glucose control and body weight for patients with prediabetes. Participants will have screening (includes blood draw) and baseline testing with a continuous glucose monitor. Once these enrollment steps are completed and the participants will be randomized to one of two groups: standard National Diabetes Prevention Program (NDPP) or a very low-carbohydrate version. In addition to the diet (12 months) participants will be asked to participate in hour-long weekly group classes over zoom. After four months in the program, classes will occur about every month to help participants maintain the new diet. There will also be check-ins and follow-up visits through out the study.

Official Title
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Testing a Very Low-carbohydrate Diet Version of the Diabetes Prevention Program to Reduce Risk Factors for Type 2 Diabetes: The LEAP (Lifestyle Education About Prediabetes) Study

Conditions
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PreDiabetes

Intervention / Treatment
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* Behavioral: Standard NDPP
* Behavioral: Very low-carbohydrate diet


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: overweight, defined as BMI >= 25 kg/m2 >= 23 kg/m2 if of Asian descent HbA1c between 5.7% - 6.4% verified at baseline willingness to participate in group-based sessions able to engage in at least light physical activities such as walking willingness to follow a prescribed diet, be randomized, self-weight, track diet, and report physical activity minutes physician approval to participate Exclusion Criteria: history of type 1 diabetes or type 2 diabetes use of anti-obesity medications or participation in another weight loss program or intervention use of glucose lowering medications other than metformin pregnant or planning to become pregnant during the intervention period breastfeeding use of oral corticosteroids previous bariatric surgery or planning to have bariatric surgery during the study period blood disorders that influence HbA1c, including frequent blood transfusions, phlebotomy, anemia, hemoglobinopathy, polycythemia any condition for which the study team deems participation to be unsafe or inappropriate inability to read, write, or speak English inability to provide informed consent adherence to a vegan or vegetarian diet adherence to a very low-carbohydrate (keto) diet difficulty chewing or swallowing no influence over what foods are purchased, prepared, and/or served above weight limit for DEXA (500 pounds) untreated eating disorder or mental health conditions, such as depression with suicidal ideation, bipolar or schizophrenia with psychosis use of warfarin chronic kidney disease, stage 4 or higher use of loop diuretics: 20mg or higher of furosemide or equivalent (Lasix (furosemide), Bumex (bumetanide), Ederin or Sodium Edecrin (ethacrynic acid), Demadex or Soaanz (torsemide)) any concerning values in baseline labs (participants will be referred to Primary Care Physician and will be allowed to return for later enrollment if labs are no longer concerning) Triglycerides 600 Milligrams per deciliter (mg/dL) or higher Thyroid stimulating hormone of any abnormal value Potassium of any abnormal value

Ages Eligible for Study
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Minimum Age: 21 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: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Standard NDPP<br>12-month long, calorie-restricted NDPP | Behavioral: Standard NDPP<br>* Participants in this arm will be taught to manage their prediabetes with the Centers for Disease Control's standard National Diabetes Prevention Program. It teaches a lower calorie, lower fat diet. There will be a core phase and a maintenance phase of this study; the core phase will last for about 4 months and will involve weekly or every other week classes, home assignments, and brief check-in surveys. The maintenance phase will last for the remaining time, with classes and check-in surveys approximately once a month.<br>|
| Experimental: Very low-carbohydrate diet (VLCD)<br>VLCD is an adaptation of the standard NDPP curriculum, which preserves all features with the exception of altered dietary advice. | Behavioral: Very low-carbohydrate diet<br>* Participants in this arm will be taught to manage their prediabetes with the Centers for Disease Control's National Diabetes Prevention Program, adapted to teach a very low-carbohydrate diet, also called a ketogenic or keto diet. This diet involves eating non-starchy vegetables, leafy greens, cheese, meats, berries, nuts, and seeds and avoiding starchy foods like pasta, bread, rice, beans, many fruits, etc. There will be a core phase and a maintenance phase of this study; the core phase will last for about 4 months and will involve weekly or every other week classes, home assignments, and brief check-in surveys. The maintenance phase will last for the remaining time, with classes and check-in surveys approximately once a month.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in HbA1c | HbA1c levels will be measured by standard immunoturbidimetric assay methods and quality control measures at a Clinical Laboratory Improvement Amendments (CLIA) certified lab. | 0 to 12 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Inflammation based on C-reactive protein (CRP) | High-sensitivity C-reactive protein will be measured with nephelometric methods utilizing latex particles coated with CRP monoclonal antibodies and standardized against a CRP reference preparation. | 0 to 12 months | 
| Change in percent body weight loss |  | 0-12 months | 
| Change in glycemic variability | This will be measured with an Abbott Libre Pro continuous glucose monitoring device on participants upper arm and the information on the sensor is blinded to participants. The monitoring device will record participants' glucose levels in the interstitial fluid by a glucose oxidase method every 15 minutes, continuously for 14 days at each time point. T The glucose variability and the proportion of time spent in the euglycemic (3-7.8 millimoles per litre (mmol/l)) and hyperglycemic (≥ 11.1 mmol/l for at least 15 minutes) states, following previous standards for interstitial glucose concentrations. | 0 to 12 months | 
| Change in small particle low-density lipoproteins (LDL) |  | 0 to 12 months | 
| Change in high-density lipoproteins (HDL) |  | 0 to 12 months | 
| Change in triglycerides |  | 0 to 12 months | 
| Change in HbA1c | HbA1c levels will be measured by standard immunoturbidimetric assay methods and quality control measures at a Clinical Laboratory Improvement Amendments (CLIA) certified lab. | 0 to 4 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Diabetes Prevention Program, Nutrition therapy, Very low carbohydrate diet