Response of the Gut Microbiome and Circulating Metabolome to Diet in Children: Ancillary Study to KIDFIT (NCT03405246)

Study Overview
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Brief Summary
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This is an ancillary study to KIDFIT (NCT03405246). KIDFIT tests whether preschool-age children, born to overweight or obese mothers, respond to a healthy DASH diet intervention with better cardiovascular health. This ancillary study to KIDFIT investigates how the children's gut microbiomes (bacteria in the intestines) and blood metabolomes (small molecules in the blood) are affected by the DASH diet intervention, and how the microbiome and metabolome relate to the children's cardiovascular health over time. The investigators hypothesize that (1) the DASH diet will modify the gut microbiome and blood metabolome, (2) the gut microbiome and blood metabolome will be related to each other, and (3) the microbiome and metabolome will be associated with the children's cardiovascular health profiles (things like weight, body fat, blood pressure, and cholesterol).

Detailed Description
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The majority of deaths from cardiovascular disease (CVD) in US adults ages 25-54 years are associated with suboptimal diet. While diet is an important target of CVD prevention efforts in adults, intervention on the childhood diet may be more effective. Animal data suggest that early-life diet has the unique potential to modulate biological systems and durably program a child's biology for long-term health or disease. The objective of this study is to define the molecular effects of a dietary pattern intervention on the gut microbiome and circulating metabolome in young children. This objective will be attained through an ancillary study to KIDFIT, a clinical trial that tests the effects of a 12-month Dietary Approaches to Stop Hypertension (DASH) diet intervention on adiposity and other cardiovascular health (CVH) metrics (e.g., blood pressure, lipids) in 3- to 5-year old children. Using additional participant samples, deep phenotyping and advanced bioinformatics, the ancillary study will address three specific aims. First, it will test the effect of the DASH diet intervention on the gut microbiome, including abundances of microbial taxa, communities, and metabolism-related genes and transcripts. Second, it will define the associations of diet and the gut microbiome with the circulating metabolome. Using targeted and nontargeted metabolomics approaches, blood metabolites, metabolite networks, and metabolic pathways will be evaluated. Finally, in an exploratory fashion, it will probe pathways linking the diet intervention with subsequent adiposity and CVH metrics, through the gut microbiome and serum metabolome. The expected outcome is a preliminary model of how the DASH diet alters the gut microbiome and circulating metabolome in young children, and how these alterations relate to short-term CVH outcomes.

Official Title
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Response of the Gut Microbiome and Circulating Metabolome to Diet Intervention in Young Children: Ancillary Study to the Keeping Ideal Cardiovascular Health Family Intervention Trial (KIDFIT)

Conditions
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Gastrointestinal Microbiome, Metabolome, Pediatric Obesity, Dietary Approaches to Stop Hypertension

Intervention / Treatment
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* Behavioral: KIDFIT Healthy
* Behavioral: KIDFIT Safe


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: - participating in KIDFIT (NCT03405246) Exclusion Criteria: - none

Ages Eligible for Study
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Minimum Age: 3 Years
Maximum Age: 5 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: KIDFIT Healthy<br> | Behavioral: KIDFIT Healthy<br>* The KIDFIT Healthy intervention promotes the DASH diet, physical activity, limited screen time, and adequate sleep, through a combination of traditional in-person and electronic participant contacts. See NCT03405246 for details.<br>* Other names: Intervention Group;|
| Active Comparator: KIDFIT Safe<br> | Behavioral: KIDFIT Safe<br>* The KIDFIT Safe active control provides electronic material about safe home environments and activities (e.g., sun screen, choking hazards, pet safety) for children. See NCT03405246 for details.<br>* Other names: Control Group;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Gut microbiome | abundances of gut microbial taxa, communities, and metabolic pathways activity | changes from baseline to 12 months | 
| Blood metabolome | abundances of blood metabolites, metabolic networks, and metabolic pathways activity | changes from baseline to 12 months |