Low-calorie Diet in Isolated Impaired Fasting Glucose
- Conditions
- Isolated Impaired Fasting Glucose
- Interventions
- Behavioral: Routine dietary and physical activity habitsBehavioral: Low-calorie diet
- Registration Number
- NCT06451055
- Lead Sponsor
- Emory University
- Brief Summary
This study aims to evaluate the preliminary efficacy of a low-calorie diet (LCD) intervention in addressing the underlying pathophysiological abnormalities and improving fasting hyperglycemia among individuals with isolated impaired fasting glucose (i-IFG). Additionally, it seeks to assess the feasibility and acceptability of the LCD intervention.
- Detailed Description
This proof-of-concept randomized controlled trial (RCT) will enroll 34 individuals aged 35-65 years with overweight or obesity and isolated impaired fasting glucose. Intervention participants will adhere to an 8-week low-calorie dietary (LCD) regimen (\~1,320 kcal/day) comprising specific macronutrient proportions (55% carbohydrate, 13% fat, 25% protein, and 2% fiber). Control participants will maintain their habitual dietary habits and physical activity levels. Primary outcomes at 8 weeks include between-group changes in weight, fasting plasma glucose, indices of ß-cell function and hepatic insulin resistance, and alanine aminotransferase levels. Secondary outcomes are feasibility metrics (response rate, screening yield, enrollment rate, intervention compliance, cost, staff time, and retention rate) and intervention acceptability. Qualitative research will explore facilitators, barriers, acceptability, satisfaction, and participant experiences with the LCD intervention.
Recruitment & Eligibility
- Status
- NOT_YET_RECRUITING
- Sex
- All
- Target Recruitment
- 34
- Aged 35 to 65 years
- Overweight (body mass index (BMI) ≥25 to <29 kg/m² or ≥23 to <29 kg/m² if Asian descent) or Obese (BMI ≥30 kg/m²)
- Physically inactive (<150 minutes per week of moderate-intensity physical activity or <75 minutes per week of vigorous-intensity physical activity)
- Prediabetes diagnosis or score ≥5 on the American Diabetes Association (ADA) risk tool
- Diagnosed with type 1 or type 2 diabetes
- Cardiovascular disease (myocardial infarction, stroke, angina, heart failure, or other cardiac conditions)
- Chronic kidney disease
- Chronic liver disease (e.g., cirrhosis)
- Cancers
- Acute inflammatory bowel disease, irritable bowel syndrome, celiac disease, chronic pancreatitis, or other disorders potentially causing malabsorption
- Food allergies
- Participation in weight loss programs in the past six months
- Currently following a specific diet (e.g., ketogenic diet, Mediterranean diet)
- Participation in any exercise programs in the past six months
- Currently taking weight-loss medications or drugs known to affect glycemia (steroids and antipsychotics)
- Previous bariatric surgery or plan to have bariatric surgery during the study period
- Planning to relocate during the study period
- Intending to fast during the study period for religious or other reasons
- Pregnancy or planning to become pregnant during the study period
- Breastfeeding
- Non-English speaker
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- PARALLEL
- Arm && Interventions
Group Intervention Description Routine dietary and physical activity habits Routine dietary and physical activity habits Control participants will be asked to maintain their routine dietary and physical activity habits. Low-calorie diet Low-calorie diet Participants will be placed on a low-calorie diet regimen consisting of \~1,300 kcal/day (55% carbohydrates, 13% fat, 25% protein, and 2% fiber) over 8 weeks. They will receive weekly pre-prepared meals (breakfast, lunch, and dinner) meticulously crafted by certified dieticians and expert chefs. Participants will be instructed to store the meals in the fridge or freezer and heat them using an air fryer, oven, microwave, or stovetop. They will be encouraged to consume 1-2 liters of water daily and maintain their habitual physical activity levels. A weight loss goal of at least 10% is set for the participants. Upon completion of the 8-week intervention, participants will transition back to their habitual dietary patterns while receiving guidance on portion sizes and healthy eating practices.
- Primary Outcome Measures
Name Time Method Response rate Baseline Response rate is defined as the proportion of individuals responding to the invitation sent via the Epic database.
Screening yield Baseline Screening yield: Proportion of screened individuals meeting eligibility criteria.
Enrollment rate Baseline Enrollment rate: Proportion of eligible individuals who enroll in the study.
Resource utilization Throughout the study period, an average of 10 weeks Resource utilization: Assessment of expenditures and staff time.
Retention rate 4 and 8 weeks Retention rate: Proportion of enrolled participants who complete the study.
Intervention acceptability 4 and 8 weeks Intervention acceptability will be assessed using the Theoretical Framework of Acceptability questionnaire. Scores range from 7 to 35. Higher scores indicate better acceptability among participants.
Feasibility of intervention 4 and 8 weeks Will be assessed using the Feasibility of Intervention Measure questionnaire. Scores range from 4 to 20. Higher scores indicate better feasibility among participants.
Intervention appropriateness 4 and 8 weeks Will be assessed with the Intervention Appropriateness Measure questionnaire. Scores range from 4 to 20. Higher scores indicate better appropriateness among participants.
Facilitators, barriers, acceptability, satisfaction, and participant experiences with the the intervention 4 and 8 weeks Qualitative in-depth interviews
- Secondary Outcome Measures
Name Time Method Weight in kg 4 and 8 weeks Weight will be measured using a digital weighing scale with an accuracy to the nearest 0.1 kg
Fasting plasma glucose in mg/dl 4 and 8 weeks Will be analyzed by enzymatic assays
Indices of ß-cell function 4 and 8 weeks Will be assessed using the insulinogenic index (IGI)
ß-cell function assessed by Oral Disposition Index (DI(O)) 4 and 8 weeks Will be assessed using the Oral Disposition Index (DI(O))
ß-cell function assessed by Homeostatic Model Assessment of ß-cell Function (HOMA-B) 4 and 8 weeks Will be assessed using the Homeostatic Model Assessment of ß-cell Function (HOMA-B)
Indices of hepatic insulin resistance 4 and 8 weeks Will be assessed using the Hepatic Insulin Resistance Index (HIRI)
Alanine aminotransferase (liver enzyme) in U/L 4 and 8 weeks Will be analyzed with colorimetric assays
Trial Locations
- Locations (1)
Georgia Clinical & Translational Science Alliance (CTSA) Clinical Research Centers (GCRCs)
🇺🇸Atlanta, Georgia, United States