Changes in Sugar-sweetened Beverage Intake and Metabolic Health: Improving Metabolic Profile Very Effortlessly

Study Overview
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Brief Summary
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Sugar-sweetened beverages (SSBs) have been epidemiologically linked to serious health problems including heart disease, liver disease, and diabetes. This study will recruit frequent SSB drinkers who are employees at the University of California, San Francisco (UCSF) and measure markers of metabolic health on two occasions, 10 months apart. During this time, UCSF will cease selling SSBs at all campus and medical center locations. Additionally, at the first assessment half of participants will be randomly assigned to a brief intervention to help reduce SSB consumption, consisting of a 10-20 minute semi-structured interview designed to share health information about SSBs, elicit motivations to reduce consumption, and help set concrete plans to reduce consumption. The investigators will be able to compare changes in metabolic health among those who do and do not reduce SSB consumption. This will make a unique contribution to the growing evidence regarding both the effects of SSB consumption on health and the modifiability of SSB-related health conditions.

Detailed Description
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Sugar-sweetened beverages (SSBs) have been epidemiologically linked to serious health problems including heart disease, liver disease, and diabetes. This study will recruit frequent SSB drinkers who are employees at the University of California, San Francisco (UCSF) and measure markers of metabolic health on two occasions, 10 months apart. During this time, UCSF will cease selling SSBs at all campus and medical center locations. Additionally, at the first assessment half of participants will be randomly assigned to a brief intervention to help reduce SSB consumption, consisting of a 10-20 minute semi-structured interview designed to share health information about SSBs, elicit motivations to reduce consumption, and help set concrete plans to reduce consumption. We will be able to compare changes in metabolic health among those who do and do not reduce SSB consumption. This will make a unique contribution to the growing evidence regarding both the effects of SSB consumption on health and the modifiability of SSB-related health conditions. Two key clarifications about the design of this study: The cessation of sugar-sweetened beverage sales is a pre-existing workplace initiative. This study is taking advantage of its initiation but it is not part of the study intervention. The primary predictor in this study is SSB consumption, not condition assignment. Although we will report on the efficacy of the brief intervention, the main goal of the study is to examine the correlational relationship between changes in SSB consumption and changes in health, whether the reduction is associated with the intervention or with other factors. Planned analyses: For all outcomes other than sugar consumption and SSB consumption (see below), the primary analytic strategy will be to correlate changes in SSB consumption with changes in the outcome. We will additionally assess the efficacy of the university initiative and the brief counseling intervention using a linear mixed regression model estimating the effects of 1) time (pre to post), representing the effect of the university SSB initiative, and 2) assignment to the brief intervention interacting with time. For both types of analysis, we will include demographic and job-related covariates based on fit criteria to guide model selection.

Official Title
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Effects of Sugar-sweetened Beverage Consumption Changes on Metabolic Health: Improving Metabolic Profile Very Effortlessly (IMPROVE)

Conditions
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Metabolic Health

Intervention / Treatment
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* Behavioral: Brief intervention


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Employed at UCSF Reports drinking an average of 60oz or more of sugar-sweetened beverages per week (approximately 8oz/day), over the past month. Exclusion Criteria: Unwilling or medically advised not to fast in preparation for a fasting blood draw Reports vasovagal response (fainting) following blood draws or needle sticks in the past. Pregnant (health outcome measures from pre- to post-partum will not be comparable). Diagnosed with diabetes (type 1 or type 2) Not fluent in English
Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

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


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: Observation<br> | |
| Experimental: Brief intervention<br> | Behavioral: Brief intervention<br>* An interviewer provides health information, elicits motivation to reduce SSB consumption, and helps participants make implementation plans. Booster phone calls occur at 1 week after the intervention visit, and at 2 weeks and 24 weeks following the date on which SSBs sales ended at the participant's work location.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Homeostatic Model Assessment ratio (HOMA) | insulin sensitivity measure derived from fasting glucose and insulin | 10 month minus baseline | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Waist-hip circumference ratio | A measure of abdominal adiposity | 10 month minus baseline | 
| Consumption of sugar-sweetened beverages | outcome for intervention efficacy analysis only | 2 weeks post-SSB sales ban (1-3 months after initial visit) minus baseline | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Sugar-Sweetened beverages, Metabolic health, Soft drinks