Low Fat Vegan or American Heart Association Diets & Cardiovascular Risk in Obese 9-18 y.o. With Elevated Cholesterol

Not Applicable

Completed

Conditions: Obesity
Cardiovascular Disease
Hypercholesterolemia
Fatty Liver

Interventions: Other: American Heart Association Diet
Other: Reduced Fat Vegan Diet

Registration Number: NCT01817491

Lead Sponsor: The Cleveland Clinic

Brief Summary: The purpose of this study is to investigate the short-term effects of a reduced fat plant-based diet on biomarkers of inflammation, oxidative stress and cardiovascular risk. This plant-based diet consists of whole grains, fruits and vegetables and little amounts of nuts and seeds, with no limitations on the amount of food intake. Animal products are not allowed. The results of the plant-based diet will be compared with the diet recommended by American Heart Association. This diet also emphasizes fruits and vegetables, but allows healthy fats, low-fat meats, fish and low-fat dairy in moderation. The results of the study might be useful in understanding whether or not plant-based diets are protective against cardiovascular disease.

Detailed Description: Scientific Question: In obese, hypercholesterolemic (\>169 mg/dl) 9-18 year olds and one of their parents are biomarkers of inflammation, oxidative stress and cardiovascular risk significantly reduced after a randomized 4 week trial of a reduced fat, vegan diet, or the American Heart Association (AHA) diet (which also encourages fruits, vegetables and whole grains, but permits low fat meat and dairy, and fish)? Rationale: "Cardiovascular disease remains the leading cause of death in North Americans, but manifest disease in childhood and adolescence is rare. By contrast, risk factors and risk behaviors that accelerate the development of atherosclerosis begin in childhood, and there is increasing evidence that risk reduction delays progression toward clinical disease". Myeloperoxidase is an early biomarker of inflammation, oxidative stress and cardiovascular risk in prepubertal obese children and is over expressed in children with hypercholesterolemia. Trimethylamine N-oxide, global arginine bioavailability ratio, arginine methylation index, paraoxonase 1 gene, and F2-isoprostane are all also associated with future major adverse cardiovascular events. Studies have suggested that a low-fat, vegan diet is effective in promoting weight loss, lowering body mass index, improving lipoprotein profiles, insulin sensitivity and in preventing cardiovascular disease in overweight individuals. Vegetarian diets have been shown to not only prevent but also to reverse heart disease in adults. Dietary habits (e.g. vegan/vegetarian versus omnivore/carnivore) are associated with significant alterations in intestinal microbiota composition and function. The diet-microbe interaction may play a significant role in the cardiovascular protective effects of a vegan/vegetarian diet. One small report of 15 adults on a reduced fat, vegan "Engine 2 Diet" for four weeks reported decreases in mean total cholesterol from 197 mg/dl to 135 mg/dl and mean LDL cholesterol falling from 124 mg/dl to 74 mg/dl.

Innovation: This is the first randomized trial comparing a low fat vegan diet to the standard AHA diet. If one diet proves superior in this brief pilot study, future larger long term studies will be needed to clearly define the health implications of our results.

Methods: Obese hypercholesterolemic children ages 9-18 will be identified by reviewing medical records and recruited initially by letters. Child, parent/guardian pairs will be randomly assigned to either the reduced fat vegan diet or the AHA diet.

During the 4-week study, participants will be asked to attend a group teaching and cooking session once a week on Saturday to learn about their assigned diets. The participants will also be requested to record their diet history on 2 weekdays and 1 weekend day before and again during the 4 weeks of the study.

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 60

Inclusion Criteria

Children ages 9-18
BMI > 95th percentile
Hypercholesterolemia (>169 mg/dl)

Exclusion Criteria

Pregnant women
Patients already on vegetarian diets

Study & Design

Study Type: INTERVENTIONAL

Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
American Heart Association Diet	American Heart Association Diet	Diet emphasizing fruits, vegetables and whole grains but also low fat dairy, low fat meat and fish.
Reduced Fat Vegan Diet	Reduced Fat Vegan Diet	Plant based diet with as few added oils and fats as possible.

Primary Outcome Measures

Name	Time	Method
Change in Circumference	baseline, 4 weeks
Change in Liver Enzymes	baseline, 4 weeks
Change in Blood Pressure (BP)	baseline, 4 weeks
Change in IL-6 (Interleukin-6)	baseline, 4 weeks
Change in MPO (Myeloperoxidase)	baseline, 4 weeks
Children Change in BMI Z Score	baseline, 4 weeks	Body mass index z-scores, also called BMI standard deviation (s.d.) scores, are measures of relative weight adjusted for child age and sex. Given a child's age, sex, BMI, and an appropriate reference standard, a BMI z-score (or its equivalent BMI-for-age percentile) can be determined. Negative BMI z-scores indicate a BMI that is lower than the population mean, while positive BMI scores indicate a value that is higher than the population mean. A decrease in the BMI z-score over time indicate a lowering of the BMI. Z-scores of 1.03 and 1.64 correspond to the 85th and 95th percentiles of BMI-for-age, which are the definitions of overweight and obesity in children.
Change in Body Mass Index BMI Percentile	baseline, 4 weeks
Change in Lipid Profile	baseline, 4 weeks
Change in PAQ (Physical Activity Questionnaire)	baseline, 4 weeks	PAQ self reported questions based on activity level from 1 (low activity) to 5 (high activity), overall PAQ score is a mean of the questions.
Change in hsCRP (High-sensitivity C-reactive Protein)	baseline, 4 weeks
Change in Insulin	baseline, 4 weeks
Change in Weight	baseline, 4 weeks
Change in Glucose	baseline, 4 weeks
Change in HgbA1c (Hemoglobin A1c)	baseline, 4 weeks

Secondary Outcome Measures

Name	Time	Method
PB/AHA - Adjusted Mean Difference PAQ Children	Baseline, 4 weeks	PAQ self reported questions based on activity level from 1 (low activity) to 5 (high activity), overall PAQ score is a mean of the questions.
PB/AHA - Adjusted Mean Lipid Profile	Baseline, 4 weeks
PB/AHA - Adjusted Mean Difference BMI	Baseline, 4 weeks
PB/AHA - Adjusted Mean Ratio MPO	Baseline, 4 weeks
PB/AHA - Adjusted Mean Ratio HgbA1c	Baseline, 4 weeks
PB/AHA - Adjusted Mean Difference Circumference	Baseline, 4 weeks
PB/AHA - Adjusted Mean Difference Weight	Baseline, 4 weeks
PB/AHA - Adjusted Mean Ratio Glucose	Baseline, 4 weeks
PB/AHA - Adjusted Mean Ratio Liver Enzymes	Baseline, 4 weeks
PB/AHA - Adjusted Mean Difference BMI Z Score Children	Baseline, 4 weeks
PB/AHA - Adjusted Mean Ratio hsCRP	Baseline, 4 weeks
PB/AHA - Adjusted Mean BP	Baseline, 4 weeks
PB/AHA - Adjusted Mean Ratio IL-6	Baseline, 4 weeks
PB/AHA - Adjusted Mean Ratio Insulin	Baseline, 4 weeks