Clinical trial NCT05293340: Continuous Glucose Monitoring and Hass Avocado Trial ("CHAT")
Official title: Avocado Voucher Impact on Health Outcomes in Hispanic/Latino Adults With or At-risk of Type 2 Diabetes
Study type: INTERVENTIONAL
Overall status: TERMINATED
Phase: NA
Conditions: Dietary Habits
Diabetes Mellitus, Type 2
Keywords: Glycemic control
Minority Health
Plants, Edible
Food prescriptions
Food security
Time in Range
Lead sponsor: Sansum Diabetes Research Institute
Sponsor class: OTHER
Collaborators: name: Hass Avocado Board
First posted: 2022-03-24
Enrollment: 50
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Intervention model description: This study will consist of two groups into which participants will be randomly assigned 1:1. One (active) group will receive vouchers for free avocados. The other (control) group will not receive avocado vouchers (to control for the impact of seasonal changes on diet that are outside the influence of the trial).
Primary purpose: PREVENTION

Brief summary: Hispanic/Latino adults in the United States (U.S.) bear a disproportionate burden of type 2 diabetes (T2D). Dietary changes, facilitated by increased access and adherence to healthy foods, are necessary. In this study, continuous glucose monitoring (CGM) will be used to quantify changes in glycemic control in Hispanic/Latino (predominantly of Mexican origin) adults with or at-risk of T2D before and after receiving free avocados for 12 weeks. Beyond CGM-measured glycemic control, wearable activity and sleep monitors, physical exams, laboratory analyses, and questionnaires/logs will be used to track the impact of free avocado vouchers. The findings are anticipated to help clinicians provide new information to support positive behavior change to reduce the risk of T2D or progression from pre-diabetes to T2D and make it easier for patients to access healthier food, potentially leading to improved health.

Detailed description: In this study, continuous glucose monitoring (CGM) will be used to quantify changes in glycemic control in Hispanic/Latino adults with and at-risk of T2D before and after receiving free avocado vouchers. The impact of using CGM to determine the effect of improving access to avocados on glycemic profiles and food related-behaviors for Hispanic/Latino adults with or at risk of T2D is not known at present. To address this need, increased avocado consumption will be combined with CGM to assess post-prandial glucose responses. This is based on evidence showing that one half of a Hass avocado at lunch is associated with increased satisfaction and reduced desire to eat over the subsequent 3-5 hours in overweight or obese adults.

For CGM, there is a lack of prospective data on the relationship between derived metrics and complications for adults with non-insulin treated T2D or at-risk of T2D, but glucose profiles from non-diabetic subjects suggest very tight glycemic control, with only brief postprandial excursions \>140 mg/dL. Cross-sectional data suggests more time spent between 140 and 180 mg/dl comparing predominantly Mexican American adults at risk of T2D to adults with pre-T2D and to adults with diagnosed T2D. Further, in a study examining the thresholds for CGM at which vascular disease can be detected, Lu and colleagues reported time in ranges above 140 mg/dL was associated with abnormal values for retinopathy and carotid intima-medial thickness, a measure of macrovascular disease risk. Hence, the focus in this study will be time in range between 140 and 180 mg/dl between 6 am and 12 am (waking hours).

Eligibility criteria: Inclusion Criteria:

1. Adults ≥ 18 years of age at enrollment.
2. Self-reported Hispanic/Latino heritage.
3. Self-reported diagnosis of T2D or self-reported as at risk for developing T2D using the American Diabetes Association diabetes risk assessment tool \[25\].

Exclusion Criteria:

1. Use of insulin
2. Pregnancy
3. Any active clinically significant disease or disorder which in the investigator's opinion could interfere with participation in the study.

Primary outcomes:
measure: Time in range (TIR) between 140 and 180 mg/dL [TIR (140-180)]- Change from Prior to Intervention, to Final Two Weeks of Intervention
timeFrame: Prior to Intervention (Week 0), and During Final 2 Weeks of Intervention (Week 13 or 14)
Secondary outcomes:
measure: Waist Circumference- Change from Enrollment Visit to Study Conclusion Visit
timeFrame: At Enrollment Visit and at 14 weeks from Enrollment Visit
measure: Blood Pressure- Diastolic and Systolic- Change from Enrollment Visit to Study Conclusion Visit
timeFrame: At Enrollment visit and at 14 weeks from Enrollment Visit
measure: HbA1c- Change from Enrollment Visit to Study Conclusion Visit
timeFrame: At Enrollment Visit and at 14 weeks from Enrollment Visit
measure: Insulin resistance- Change from Enrollment Visit to Study Conclusion Visit
timeFrame: At Enrollment visit and at 14 weeks from enrollment visit
measure: Lipids- Change from Enrollment Visit to Study Conclusion Visit
timeFrame: At enrollment visit and at 14 weeks from enrollment visit
measure: Prescribed medicines for T2D and/or hypertension- Change from Enrollment Visit to Study Conclusion Visit
timeFrame: At enrollment visit and at 14 weeks from enrollment visit
measure: Self-reported sleep, mood, and pain via 100 mm Likert scale questionnaire- Change from Enrollment, and to Final Visit
timeFrame: At enrollment visit, and at 14 weeks from enrollment visit
measure: Self-reported Food security via United States Dept. of Agriculture U.S. Household Food Security Survey Module: Six-Item Short Form - Change from Enrollment, and at Final Visit
timeFrame: At enrollment visit, and at 14 weeks from enrollment visit
measure: Depression via the Depression, Anxiety and Stress Scale (DASS-21)
timeFrame: At enrollment visit, and at 14 weeks from enrollment visit
measure: Anxiety via the Depression, Anxiety and Stress Scale (DASS-21)
timeFrame: At enrollment visit, and at 14 weeks from enrollment visit
measure: Stress via the Depression, Anxiety and Stress Scale (DASS-21)
timeFrame: At enrollment visit, and at 14 weeks from enrollment visit
measure: Change in Eating Self-Efficacy Scale (ESES) score
timeFrame: Prior to intervention (Week 0), and during final 2 weeks of intervention (Week 13 or 14)
measure: Change in Self-Report Habit Index (SRHI) score
timeFrame: Prior to intervention (Week 0), and during final 2 weeks of intervention (Week 13 or 14)
measure: Change in Self-Regulation of Eating Questionnaire (SREBQ) score
timeFrame: Prior to intervention (Week 0), and during final 2 weeks of intervention (Week 13 or 14)
measure: Physical Activity- Daily step count, Changes from first to final Fitbit application
timeFrame: First Fitbit application (pre-intervention) to second Fitbit application (in final 14 days of intervention)
measure: Sleep Duration
timeFrame: First Fitbit application (pre-intervention) to second Fitbit application (in final 14 days of intervention)
measure: Secondary Continuous Glucose Monitoring Endpoints- Time in Range (TIR) 140-180 mg/dl, Waking Hours
timeFrame: first CGM application (pre-intervention) to second CGM application (in final 14 days of intervention).
measure: Secondary Continuous Glucose Monitoring Endpoints- Average Glucose
timeFrame: first CGM application (pre-intervention) to second CGM application (in final 14 days of intervention).
measure: Secondary Continuous Glucose Monitoring Endpoints- Time in Range (TIR) 70-180 mg/dL
timeFrame: first CGM application (pre-intervention) to second CGM application (in final 14 days of intervention).
measure: Secondary Continuous Glucose Monitoring Endpoints- Time >180 mg/dL
timeFrame: first CGM application (pre-intervention) to second CGM application (in final 14 days of intervention).
measure: Secondary Continuous Glucose Monitoring Endpoints- Time <70 mg/dL
timeFrame: first CGM application (pre-intervention) to second CGM application (in final 14 days of intervention).
measure: Adherence to the intervention
timeFrame: 12-week intervention monitoring period running weeks 2-14
measure: Acceptability of the intervention
timeFrame: 12-week intervention monitoring period running weeks 2-14
measure: Regression analysis between avocado adherence measured as an average number of avocados consumed as reported via the daily avocado consumption log (DACL) and personality traits assessed via the Mini International Personality Item Tool.
timeFrame: Average over 12 weeks
measure: Regression analysis between the average number of avocados consumed as reported via the daily avocado consumption log (DACL) and motives underlying the selection of food assessed by the Food Choice Questionnaire (FCQ)
timeFrame: Average over 12 weeks
measure: Regression analysis between average composite acceptability score on the weekly Avocado Acceptability Questionnaire and Personality traits assessed via the Mini International Personality Item Tool.
timeFrame: Average over 12 weeks
measure: Regression analysis between average composite acceptability score on the weekly Avocado Acceptability Questionnaire and motives underlying the selection of food assessed by the Food Choice Questionnaire (FCQ)
timeFrame: Average over 12 weeks
Other outcomes:
Locations:
city: Santa Barbara
country: United States
facility: Sansum Diabetes Research Institute
state: California
Study officials:
affiliation: Sansum Diabetes Research Institute
name: David Kerr, MBChB
role: PRINCIPAL_INVESTIGATOR
References: