FEED-Cystic Fibrosis (FEED-CF)
Trial statusRecruiting
Trial phaseNot applicable
Trial typeInterventional
Biological sexAll
Age18+
SponsorEmory University
About this trial
The goal of this study is to determine the extent to which excess dietary sugars serve as a precipitating factor in glucose intolerance in adults with cystic fibrosis (CF), a population at especially high risk for a unique form of diabetes (CF-related diabetes, CFRD) and with standard-of-care dietary recommendations (high-calorie, high-fat) that conflict with recommendations for other forms of diabetes.
This trial will investigate if the typical high-sugar, high-fat CF diet plays a role in diabetes risk and visceral fat accumulation in people with CF. A total of 30 participants will get a low-added sugar, high-fat diet and the other 30 will get a standard CF diet with no sugar restrictions. Participants will be randomized to the diet group they are assigned. All foods will be provided for 8 weeks.
Eligibility criteria
This trial does not accept healthy volunteersQualifiers
Confirmed CF diagnosis
Ages 18 years and older
Baseline estimated daily total added sugar intake >16 tsp, as estimated from the Dietary Screener Questionnaire (DSQ).
Disqualifiers
Nocturnal tube feeds
BMI <18.5 kg/m2
Life expectancy < 12 months
Confirmed diagnosis of CFRD
Trial design
Design model
Parallel
Treatments tested in this trial
Low-added sugar, high-fat diet
Other interventionConsist of \<5% kcal from added sugars as recommended by the American Heart Association, and the glycemic index will be 45 or lower (25% lower than typical CF diet). The macronutrient composition of both study diets will reflect the general CF recommendations for macronutrients: 35-40% of total kcal from fat and 15-20% total kcal from protein.
High-added sugar, high-fat CF diet
Other interventionConsist of ≥13% kcal from added sugars and the glycemic index will be \>60. The macronutrient composition of both study diets will reflect the general CF recommendations for macronutrients: 35-40% of total kcal from fat and 15-20% total kcal from protein.
Treatment groups
60 Participants
are divided into 2 treatment groupsGroup A: Low-added sugar, high-fat diet ArmExperimental treatment 1 intervention
Group B: Typical CF diet ArmActive comparator 1 intervention
Trial outcomes
Primary outcomes
1
Change in acute insulin response to arginine (AIRarg) from baseline
Participants will undergo a Glucose-Potentiated Arginine Stimulation (GPA) Test after a 10-12 hour overnight fast to measure acute insulin (AIRarg) responses during a 230 and 340 mg/dl glucose clamp. This test will measure changes in beta cell secretory capacity.
Time frame
Baseline and 8 weeks post intervention2
Change in acute C-peptide (ACRarg) from baseline
Participants will undergo a Glucose-Potentiated Arginine Stimulation (GPA) Test after a 10-12 hour overnight fast to measure acute C-peptide (ACRarg) responses during a 230 and 340 mg/dl glucose clamp. This test will measure changes in beta cell secretory capacity.
Time frame
Baseline and 8 weeks post intervention3
Change in visceral adipose tissue from baseline
Dual energy X-ray absorptiometry (DEXA)-derived measurement of visceral adipose tissue (VAT) will be assessed with a GE Lunar iDXA machine. This will enable assessment of changes in body composition over the study.
Time frame
Baseline and 8 weeks post intervention4
Change in fasted plasma Eh[CySS] from baseline
Change in plasma Cysteine/Cystine Redox Potential (Eh\[CySS\]) will be measured.
Time frame
Baseline and 8 weeks post interventionSecondary outcomes
1
Change in Gastrointestinal Symptom Rating Scale (GSRS) scale
The GSRS is a 15 items combine into five symptom clusters: Reflux, Abdominal pain, Indigestion, Diarrhea and Constipation. Possible score range is 0-7, with 7 being the worst and 0 being the best (no symptoms).
Time frame
Baseline and 8 weeks post intervention2
Change in hepatic and pancreatic fat volume
Dual energy X-ray absorptiometry (DEXA)-derived measurement of visceral adipose tissue (VAT) for hepatic and pancreatic fat volume. Will be assessed with a GE Lunar iDXA machine.
Time frame
Baseline and 8 weeks post intervention3
Change in fasted plasma Eh[GSSG]
Change in plasma glutathione disulfide (GSSG) (Eh\[CySS\]) will be measured.
Time frame
Baseline and 8 weeks post interventionSponsors and contacts
Click on the lead sponsor to view all of their trials.
Emory University
Lead sponsor
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Collaborator
Source ClinicalTrials.gov