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Walnut Ingestion in Adults at Risk for Diabetes: Effects on Body Composition, Diet Quality, and Cardiac Risk Measures (Walnut3)

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ClinicalTrials.gov Identifier: NCT02330848
Recruitment Status : Completed
First Posted : January 5, 2015
Last Update Posted : March 26, 2020
Sponsor:
Information provided by (Responsible Party):
Griffin Hospital

Tracking Information
First Submitted Date  ICMJE April 2, 2014
First Posted Date  ICMJE January 5, 2015
Last Update Posted Date March 26, 2020
Study Start Date  ICMJE February 2012
Actual Primary Completion Date September 2013   (Final data collection date for primary outcome measure)
Current Primary Outcome Measures  ICMJE
 (submitted: January 2, 2015)
Diet Quality assessed using the Alternative Healthy Eating Index (AHEI) [ Time Frame: 6 months ]
To help the study team track any variation in dietary pattern over the course of the study, all participants will be asked at five different time points to provide information on the foods and beverages that they consumed. A 3-day food diary record will be collected along with a one 24-hour recall using a web-based Automated Self-Administered 24-Hour Recall (ASA24) (available from the National Cancer Institute at http://riskfactor.cancer.gov/tools/instruments/asa24/) which will guide them through the process of completing the recall data. Diet quality will be assessed using the Alternative Healthy Eating Index (AHEI).
Original Primary Outcome Measures  ICMJE Same as current
Change History
Current Secondary Outcome Measures  ICMJE
 (submitted: January 2, 2015)
  • Body Composition measured using bioelectrical impedance analysis and SC-240 Body Composition Analyzer [ Time Frame: 6 months ]
    Body composition will be measured using bioelectrical impedance analysis, which uses the resistance of electrical flow through the body to estimate body fat. The Tanita SC-240 Body Composition Analyzer will be used to measure body composition. The SC-240 Body Composition Analyzer measures weight and calculates body fat% and total body water% in addition to BMI.
  • Endothelial Function (EF) Assessment using the brachial artery reactivity studies (BARS) methodology [ Time Frame: 6 months ]
    The brachial artery reactivity studies (BARS) methodology employed is as described in the published, "Guidelines for Ultrasound Assessment of Endothelial-dependent Flow-mediated Vasodilation of the Brachial Artery." The measure of interest is flow-mediated dilatation of the brachial artery.
  • Anthropometric Measures [ Time Frame: 6 months ]
    Body weight will be measured using a calibrated digital scale while height will be measured by using a calibrated stadiometer. Body mass index (BMI) will be calculated as weight (kg) divided by height in meters (m) squared. Waist circumference will be measured using guidelines of the National Obesity Expert Panel Report.
  • Lipid Profile [ Time Frame: 6 months ]
    The lipid profile is determined as follows: Total cholesterol (Tchol), triglycerides (TRIG), and high-density lipoprotein (HDL) are obtained by direct measurements. Very-low-density lipoprotein (VLDL) and low-density-lipoprotein (LDL) are obtained by calculation: VLDL = TRIG/5; and LDL = Tchol - (VLDL + HDL). HDL:Tchol ratio will be used to evaluate the impact of walnuts on the lipid profile.
  • Fasting Blood Glucose [ Time Frame: 6 months ]
  • HbA1C [ Time Frame: 6 months ]
  • Physical Activity assessed by the International Physical Activity Questionnaire (IPAQ) [ Time Frame: 6 months ]
    Physical activity will be assessed by the International Physical Activity Questionnaire (IPAQ). The IPAQ is a valid and reliable tool to assess physical activity in adults. It is a more comprehensive tool containing information on weekly activities in household and yard-work activities, occupational activity, transport, leisure time physical activity and sedentary behavior.
Original Secondary Outcome Measures  ICMJE Same as current
Current Other Pre-specified Outcome Measures Not Provided
Original Other Pre-specified Outcome Measures Not Provided
 
Descriptive Information
Brief Title  ICMJE Walnut Ingestion in Adults at Risk for Diabetes: Effects on Body Composition, Diet Quality, and Cardiac Risk Measures
Official Title  ICMJE Walnut Ingestion in Adults at Risk for Diabetes: Effects on Body Composition, Diet Quality, and Cardiac Risk Measures
Brief Summary Proposed is a randomized, controlled, modified Latin square parallel design study with two treatment arms to examine walnut consumption effects on diet quality, body composition, and markers of cardiovascular risk in adults at risk for diabetes over a 6-month period. A modified crossover design (Latin square)27-29 will allow for both paired and unpaired analyses.
Detailed Description

Specific Aims

  • To determine the effects of a walnut-included diet (with or without caloric intake adjustment) versus walnut-excluded diet on diet quality in adults at risk for diabetes. Specifically, to show that a walnut-included diet, as compared to a walnut-excluded diet will improve overall diet quality as measured by the Alternative Healthy Eating Index in adults at risk for diabetes.
  • To determine the effects of a walnut-included diet (with or without caloric intake adjustment) versus walnut-excluded diet on body composition in adults at risk for diabetes. Specifically, to show that a walnut-included diet, as compared to a walnut-excluded diet for 6 months will improve body fat percentage in adults at risk for diabetes.
  • To assess the effects of a walnut-included diet (with or without caloric intake adjustment) for a 6-month period on endothelial function, lipid panel levels, fasting glucose level, fasting insulin level and anthropometric measures in adults at risk for diabetes. Specifically, to show clinically meaningful improvement in endothelial function, lipid panel, fasting blood glucose, hemoglobin A1c (HbA1c), anthropometric measures and endothelial function with inclusion of walnuts in the diet in adults at risk for diabetes.

Hypotheses

  • A walnut-included diet with or without dietary counseling to adjust caloric intake will improve diet quality in adults at risk for diabetes.
  • A walnut-included diet for 6 months with or without dietary counseling to adjust caloric intake will improve body composition in adults at risk for diabetes.
  • A walnut-included diet with or without dietary counseling to adjust caloric intake will improve lipid panel, fasting blood glucose, hemoglobin A1c, endothelial function and anthropometric measures in adults at risk for diabetes.
  • Controlling calorie intake to keep it constant with the addition of walnuts to the diet will enhance the beneficial effects of walnut ingestion on diet quality, body composition, and vascular function.
Study Type  ICMJE Interventional
Study Phase  ICMJE Not Applicable
Study Design  ICMJE Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Single (Investigator)
Primary Purpose: Prevention
Condition  ICMJE Diabetes
Intervention  ICMJE
  • Dietary Supplement: Walnut Ad libitum diet
    Participants will be provided 392 grams of walnuts per week (56g or 2 oz/day) to include in their diet. Their calorie intake will not be subsequently monitored or regulated, and thus will be allowed to float ad libitum
  • Dietary Supplement: Walnut Calorie controlled
    The intervention group participants will meet with a registered dietitian and receive instructions and recipes for inclusion of 392 grams of walnuts per week (56g or 2 oz/day) in their meal plan for 6 months.
Study Arms  ICMJE
  • Active Comparator: Walnut Ad libitum diet
    Participants will be provided 392 grams of walnuts per week (56g or 2 oz/day) to include in their diet. Their calorie intake will not be subsequently monitored or regulated, and thus will be allowed to float ad libitum.
    Intervention: Dietary Supplement: Walnut Ad libitum diet
  • Active Comparator: Walnut Calorie Controlled
    The intervention group participants will meet with a registered dietitian and receive instructions and recipes for inclusion of 392 grams of walnuts per week (56g or 2 oz/day) in their meal plan. Participants will receive on-going instruction to preserve an isocaloric condition after the addition of walnuts. The study dietitian will customize dietary adjustments to make room for walnuts in the diet, while accommodating the priorities of each study participant. The general approach will emphasize general reduction in portion sizes; participants will also receive advice, based on baseline dietary intake analysis, of food eliminations that they might want to consider.
    Intervention: Dietary Supplement: Walnut Calorie controlled
Publications *

*   Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
 
Recruitment Information
Recruitment Status  ICMJE Completed
Actual Enrollment  ICMJE
 (submitted: January 2, 2015)
112
Original Actual Enrollment  ICMJE Same as current
Actual Study Completion Date  ICMJE April 2014
Actual Primary Completion Date September 2013   (Final data collection date for primary outcome measure)
Eligibility Criteria  ICMJE

Inclusion Criteria:

  • Male and female age 25-75 years;
  • Non-smoker;
  • High risk for diabetes, defined as meeting at least one of the criteria listed below:

    a. Overweight with increased waist circumference; b.Pre-diabetes: fasting blood glucose >100mg/dL and <126mg/dL or HbA1C 5.7-6.4 % c. Metabolic syndrome, i.e. meet three out of five of the following criteria: i.Blood pressure >130/85 mmHg or currently taking antihypertensive medication; ii. Fasting plasma glucose (FPG) >100 mg/dL (6.1 mmol/L); iii.Serum triglycerides level (TG)>150 mg/dL (1.69 mmol/L); iv. High-density lipoprotein (HDL) cholesterol < 40 mg/dL (1.04 mmol/L) in men, and < 50 mg/dL (1.29 mmol/L) in women; v. Overweight (BMI ≥25kg/m²) with waist circumference of more than 40 inches (102 cm) for men and more than 35 inches (88 cm) for women.

Exclusion Criteria

  • Allergy to walnuts or any other nuts;
  • Anticipated inability to complete study protocol for any reason;
  • Current eating disorder;
  • Restricted diets by choice (i.e., vegetarian, vegan);
  • Receiving pharmacotherapy for obesity, including appetite suppressant
  • Unstable use of lipid-lowering, antihypertensive medications or aspirin (i.e. dose has changed in the three months prior to enrollment) or unwilling to refrain from taking medication for 12 hours prior to endothelial function scanning;
  • Regular use of high doses of vitamin E (>400IU/day) or vitamin C (>500mg/day); fish oil, flaxseed oil, omega-3 fatty acid and fiber supplement unless welling to discontinue supplementation for the study duration.
  • Use of insulin, glucose-sensitizing medication, vasoactive medication (including glucocorticoids, antineoplastic agents, psychoactive agents, or bronchodilators);
  • Diagnosed diabetes;
  • Diagnosed sleep apnea;
  • Established cardiovascular disease (including symptomatic coronary artery disease (CAD), myocardial infarction, peripheral vascular disease, congestive heart failure, carotid stenosis);
  • Coagulopathy, known bleeding diathesis, or history of clinically significant hemorrhage; current use of warfarin;
  • Regular exercise defined as participation in moderate-intensity exercise > 150 minutes/week.
  • Substance abuse (chronic alcoholism, other chemical dependency)
  • Any unstable medical condition that would limit the ability of a subject to participate fully in the trial (e.g., cancer, AIDS, tuberculosis, psychotic disorder)
  • Women who get Depo-Provera shots
  • Women who are pregnant or lactating
  • Women who are currently on hormone replacement therapy
  • Substance abuse (chronic alcoholism, other chemical dependency)
  • Any unstable medical condition that would limit the ability of a subject to participate fully in the trial (e.g., cancer, AIDS, tuberculosis, psychotic disorder)
Sex/Gender  ICMJE
Sexes Eligible for Study: All
Ages  ICMJE 25 Years to 75 Years   (Adult, Older Adult)
Accepts Healthy Volunteers  ICMJE No
Contacts  ICMJE Contact information is only displayed when the study is recruiting subjects
Listed Location Countries  ICMJE United States
Removed Location Countries  
 
Administrative Information
NCT Number  ICMJE NCT02330848
Other Study ID Numbers  ICMJE 2011-16
Has Data Monitoring Committee No
U.S. FDA-regulated Product
Studies a U.S. FDA-regulated Drug Product: No
Studies a U.S. FDA-regulated Device Product: No
IPD Sharing Statement  ICMJE
Plan to Share IPD: No
Responsible Party Griffin Hospital
Study Sponsor  ICMJE Griffin Hospital
Collaborators  ICMJE Not Provided
Investigators  ICMJE
Principal Investigator: David L. Katz, MD, MPH Yale-Griffin Prevention Research Center
PRS Account Griffin Hospital
Verification Date March 2020

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP