Prader-Willi Syndrome Macronutrient Study

This study is ongoing, but not recruiting participants.
Foundation for Prader-Willi Research
Information provided by (Responsible Party):
Duke University Identifier:
First received: December 10, 2013
Last updated: January 22, 2016
Last verified: January 2016

The overall objective is to explore the mechanisms by which macronutrients regulate food intake and weight gain in Prader Willi Syndrome (PWS).

Previous studies from the investigators' labs suggest that the increased appetite of PWS may be triggered or maintained by an increase in the levels of ghrelin, an appetite-stimulating hormone produced primarily by the stomach. This study will compare the effects of low carbohydrate diet versus low fat diet on levels of ghrelin, appetite suppressing hormones and markers of insulin sensitivity in patients with PWS.

The investigators hypothesize that the low carbohydrate diet will suppress plasma active ghrelin and increase appetite-suppressing hormones to a greater degree and for longer duration than the low fat diet and will thereby reduce hyperphagia and increase satiety. The investigators also hypothesize that the low carb diet will improve hormonal and metabolic markers (fatty acids, amino acids and organic acids) of insulin sensitivity and inflammatory cytokine profiles of children with PWS.

Condition Intervention
Prader Willi Syndrome
Syndromic Obesity
Childhood Obesity
Other: Low Carbohydrate diet
Other: Low Fat diet

Study Type: Interventional
Study Design: Allocation: Non-Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Crossover Assignment
Masking: Open Label
Official Title: Evidence-Based Approach to Dietary Management of Prader-Willi Syndrome (PWS)

Resource links provided by NLM:

Further study details as provided by Duke University:

Primary Outcome Measures:
  • Suppression of ghrelin [ Time Frame: 10 hour fast following completion of dietary intervention ] [ Designated as safety issue: No ]
    Fasting labs will be obtained immediately following dietary intervention. These labs will include total and active ghrelin.

Secondary Outcome Measures:
  • Changes in satiety [ Time Frame: During the 72 hour dietary intervention ] [ Designated as safety issue: No ]
    Changes in subjective hunger will be assessed by an appetite and hyperphagia questionnaire validated for PWS children. This will be completed by the children, with assistance of their parents, at completion of the 72 hour dietary intervention.

  • Improvements in insulin sensitivity [ Time Frame: During the 72 hour dietary intervention. ] [ Designated as safety issue: No ]
    The analysis will include measurements of adiponectin, GLP-1, glucose, insulin, AST, ALT, insulin sensitivity and a detailed profile ("metabolomics") of amino acids, fatty acids, acylcarnitines, and adipocytokines on the day prior to and immediately following dietary intervention.

Other Outcome Measures:
  • Improvement in inflammatory cytokine profile [ Time Frame: During the 72 hour dietary intervention ] [ Designated as safety issue: No ]
    The analysis will include measurements of adiponectin, GLP-1, glucose, insulin, AST, ALT, insulin sensitivity and a detailed profile ("metabolomics") of amino acids, fatty acids, acylcarnitines, and adipocytokines on the day prior to and immediately following dietary intervention.

Estimated Enrollment: 10
Study Start Date: May 2014
Estimated Study Completion Date: June 2016
Estimated Primary Completion Date: April 2016 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Low carbohydrate diet
Low carbohydrate diet: 15%carb; 65%fat; 20% protein. This will be administered over 72 hour hospital stay.
Other: Low Fat diet
Low Fat diet: 65%carb; 15%fat; 20% protein
Low Fat diet
Low fat diet: 65%carb; 15%fat; 20% protein. This will be administered over a 72 hour hospital stay.
Other: Low Carbohydrate diet
Low carbohydrate diet: 15%carb; 65%fat; 20% protein


Ages Eligible for Study:   5 Years to 17 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • diagnosis of Prader Willi syndrome confirmed by chromosome analysis (ie. interstitial deletion of paternally-derived chromosome 15q, uniparental maternal disomy or other chromosome 15 abnormalities)
  • age 5 years to 17 years
  • written informed consent and assent obtained and willingness to comply with the study schedule and procedures
  • free T4, TSH values in the normal range (either endogenous or with thyroxine replacement)
  • weight stable (BMI percentile fluctuation of <5 percentiles) over the preceding 2 months prior to the study

Exclusion Criteria:

  • presence of other clinically significant disease that would impact body composition including diabetes mellitus, chronic inflammatory bowel disease, chronic severe liver or kidney disease or neurologic disorders
  • concomitant use of medications known to affect body weight or investigational drug in the past year
  Contacts and Locations
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Please refer to this study by its identifier: NCT02011360

United States, North Carolina
Duke University Medical Center
Durham, North Carolina, United States, 27705
Canada, Alberta
University of Alberta
Edmonton, Alberta, Canada, T6G 2B7
Sponsors and Collaborators
Duke University
Foundation for Prader-Willi Research
Principal Investigator: Michael Freemark, MD Duke University
Principal Investigator: Andrea M Haqq, MD University of Alberta
  More Information


Responsible Party: Duke University Identifier: NCT02011360     History of Changes
Other Study ID Numbers: Pro00049226  SFR2382 
Study First Received: December 10, 2013
Last Updated: January 22, 2016
Health Authority: United States: Institutional Review Board
Canada: Ethics Review Committee

Keywords provided by Duke University:
Prader Willi syndrome
childhood obesity
appetite regulation

Additional relevant MeSH terms:
Pediatric Obesity
Prader-Willi Syndrome
Abnormalities, Multiple
Body Weight
Chromosome Disorders
Congenital Abnormalities
Genetic Diseases, Inborn
Intellectual Disability
Nervous System Diseases
Neurobehavioral Manifestations
Neurologic Manifestations
Nutrition Disorders
Pathologic Processes
Signs and Symptoms processed this record on February 04, 2016