Meta-analyses of the Effect of Tree Nuts on Glycemic Control and Features of the Metabolic Syndrome

This study is ongoing, but not recruiting participants.
Sponsor:
Collaborators:
The International Tree Nut Council Nutrition Research & Education Foundation
Canada Research Chairs Endowment of the Federal Government of Canada
Canadian Institutes of Health Research (CIHR)
Information provided by (Responsible Party):
John Sievenpiper, University of Toronto
ClinicalTrials.gov Identifier:
NCT01630980
First received: May 18, 2012
Last updated: January 10, 2014
Last verified: July 2013
  Purpose

Tree nuts (almonds, Brazil nuts, cashews, hazelnuts, macadamia nuts, pecans, pine nuts, pistachios and walnuts) are an important source of unsaturated fatty acids, vegetable protein, and fibre, as well as minerals, vitamins, and phytonutrients. Although heart disease risk reduction claims for nuts have been permitted in the U.S. and general dietary guidelines and recommendations from heart associations recommend the consumption of nuts for heart protection, diabetes associations have not addressed nuts in their most recent recommendations. This omission is despite heart disease being a major cause of death in diabetes. There remains insufficient information on the usefulness of these foods in diabetes. To improve evidence-based guidance for tree nut recommendations, the investigators propose to conduct a systematic review of the effect of tree nuts on diabetes control and features of the metabolic syndrome. The systematic review process allows the combining of the results from many small studies in order to arrive at a pooled estimate, similar to a weighted average, of the true effect. The investigators will be able to explore whether eating tree nuts has different effects between men and women, in different age groups and background disease states, and whether or not the effect of tree nuts depends on the dose and background diet. The findings of this proposed knowledge synthesis will help improve the health of Canadians through informing diabetes association recommendations and heart association recommendations where they relate to diabetes.


Condition Intervention
Diabetes
Prediabetes
Dysglycemia
Overweight
Obesity
Dyslipidemia
Hypertension
Metabolic Syndrome
Cardiovascular Disease Risk
Other: Tree nuts

Study Type: Observational
Study Design: Time Perspective: Prospective
Official Title: Effect of Tree Nuts on Glycemic Control and Features of the Metabolic Syndrome: A Systematic Review and Meta-analysis of Controlled Dietary Trials to Provide Evidence-based Guidance for Nutrition Guidelines Development

Resource links provided by NLM:


Further study details as provided by University of Toronto:

Primary Outcome Measures:
  • Glycemic control measures [ Time Frame: Up to 1.5-years ] [ Designated as safety issue: No ]
    Glycated blood proteins (HbA1c, total glycated hemoglobin, fructosamine, glycated albumin), fasting glucose, fasting insulin, and the homeostasis model assessment of insulin resistance (HOMA-IR)

  • Metabolic syndrome measures [ Time Frame: Up to 1.5-years ] [ Designated as safety issue: No ]
    Harmonized metabolic syndrome diagnostic measures (waist circumference, TG, HDL-C, blood pressure, fasting glucose)


Estimated Enrollment: 1
Study Start Date: May 2012
Estimated Study Completion Date: March 2014
Estimated Primary Completion Date: March 2014 (Final data collection date for primary outcome measure)
Intervention Details:
    Other: Tree nuts
    Almonds, Brazil nuts, cashews, hazelnuts, macadamia nuts, pecans, pine nuts, pistachios and walnuts in whole, meal, or flour form
  Show Detailed Description

  Eligibility

Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No
Sampling Method:   Probability Sample
Study Population

Varied

Criteria

Inclusion Criteria:

  • Dietary trials in humans
  • Randomized treatment allocation
  • >=3-weeks
  • Suitable control (i.e. isocaloric exchange of other dietary components for tree nuts)
  • viable endpoint data

Exclusion Criteria:

  • Non-human studies
  • Nonrandomized treatment allocation
  • 3-weeks
  • Lack of a suitable control (non-isocaloric)
  • no viable endpoint data
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT01630980

Locations
Canada, Ontario
The Toronto 3D (Diet, Digestive tract and Disease) Knowledge Synthesis and Clinical Trials Unit, Clinical Nutrition and Risk Factor Modification Centre, St. Micheal's Hospital
Toronto, Ontario, Canada, M5C 2T2
Sponsors and Collaborators
John Sievenpiper
The International Tree Nut Council Nutrition Research & Education Foundation
Canada Research Chairs Endowment of the Federal Government of Canada
Canadian Institutes of Health Research (CIHR)
Investigators
Study Director: John L Sievenpiper, MD, PhD Department of Pathology and Molecular Medicine, McMaster University and Clinical Nutrition and Risk Factor Modification Centre, St. Michael's Hospital
Study Director: Russell J de Souza, ScD, RD Department of Epidemiology and Biostatistics, McMaster University and Clinical Nutrition and Risk Factor Modification Centre, St. Michael's Hospital
Principal Investigator: Cyril WC Kendall, PhD Department of Nutritional Sciences and Medicine, University of Toronto and Clinical Nutrition and Risk Factor Modification Centre, St. Michael's Hospital
Principal Investigator: David JA Jenkins, MD, PhD, DSc Department of Nutritional Sciences and Medicine, University of Toronto and Clinical Nutrition and Risk Factor Modification Centre, St. Michael's Hospital
  More Information

Publications:
Responsible Party: John Sievenpiper, Knowledge Synthesis Lead, University of Toronto
ClinicalTrials.gov Identifier: NCT01630980     History of Changes
Other Study ID Numbers: INC 2012 KRS
Study First Received: May 18, 2012
Last Updated: January 10, 2014
Health Authority: Canada: Ethics Review Committee

Keywords provided by University of Toronto:
Systematic review and meta-analysis
Evidence-based medicine (EBM)
Evidence-based nutrition (EBN)
Clinical practice guidelines
Clinical trials
Tree nuts
Cardiometabolic risk factors
Triglycerides
Cholesterol
Glycemic control
Insulin resistance
Body weight
Blood pressure

Additional relevant MeSH terms:
Cardiovascular Diseases
Hypertension
Obesity
Dyslipidemias
Glucose Intolerance
Prediabetic State
Overweight
Metabolic Syndrome X
Vascular Diseases
Overnutrition
Nutrition Disorders
Body Weight
Signs and Symptoms
Lipid Metabolism Disorders
Metabolic Diseases
Hyperglycemia
Glucose Metabolism Disorders
Diabetes Mellitus
Endocrine System Diseases
Insulin Resistance
Hyperinsulinism

ClinicalTrials.gov processed this record on July 24, 2014