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Trial details imported from ClinicalTrials.gov

For full trial details, please see the original record at https://clinicaltrials.gov/show/NCT02629952




Registration number
NCT02629952
Ethics application status
Date submitted
3/12/2015
Date registered
15/12/2015
Date last updated
25/03/2019

Titles & IDs
Public title
Metabolic Benefits of Drinking Blueberry Tea in Type 2 Diabetes
Scientific title
Metabolic Benefits of Drinking Blueberry Tea in Type 2 Diabetes
Secondary ID [1] 0 0
H0014873
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Type 2 Diabetes 0 0
Condition category
Condition code
Metabolic and Endocrine 0 0 0 0
Diabetes

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Other interventions - Blueberry Tea

Experimental: Blueberry Tea - 3 cups of blueberry tea per day x 4 weeks

No Intervention: No Treatment - No Treatment


Other interventions: Blueberry Tea
Blueberry Tea

Intervention code [1] 0 0
Other interventions
Comparator / control treatment
Control group

Outcomes
Primary outcome [1] 0 0
Improvement in Glucose Tolerance after 4 weeks of drinking blueberry tea. - Oral glucose tolerance test (75g glucose) measured on 3 occasions: at baseline, after 4 weeks of drinking blueberry tea, and after 4 weeks of no treatment (randomized cross-over design). Blood glucose and plasma insulin levels measured at 0, 15, 30, 60, 90 and 120 min following consumption of glucose load.
Timepoint [1] 0 0
4 weeks
Secondary outcome [1] 0 0
Improvement in Hemoglobin A1c (HbA1c) levels after 4 weeks of drinking blueberry tea. - HbA1c levels measured on 3 occasions: at baseline, after 4 weeks of drinking blueberry tea, and after 4 weeks of no treatment (randomized cross-over design).
Timepoint [1] 0 0
4 weeks.
Secondary outcome [2] 0 0
Improvement in fasting Serum Lipid (cholesterol, HDL, LDL,triglycerides) levels after 4 weeks of drinking blueberry tea. - Fasting serum lipids (cholesterol, HDL, LDL,triglycerides) measured on 3 occasions: at baseline, after 4 weeks of drinking blueberry tea, and after 4 weeks of no treatment (randomized cross-over design).
Timepoint [2] 0 0
4 weeks
Secondary outcome [3] 0 0
Improvement in fasting serum pro-inflammatory cytokine (IL-6, IL-1b, CRP, TNFa) levels after 4 weeks of drinking blueberry tea. - Fasting serum pro-inflammatory cytokines (IL-6, IL-1b, CRP, TNFa) assessed by ELISA will be measured on 3 occasions: at baseline, after 4 weeks of drinking blueberry tea, and after 4 weeks of no treatment (randomized cross-over design).
Timepoint [3] 0 0
4 weeks
Secondary outcome [4] 0 0
Improvement in fasting serum albumin levels after 4 weeks of drinking blueberry tea.. - Fasting serum albumin levels measured on 3 occasions: at baseline, after 4 weeks of drinking blueberry tea, and after 4 weeks of no treatment (randomized cross-over design).
Timepoint [4] 0 0
4 weeks
Secondary outcome [5] 0 0
Fasting serum electrolytes (Na, K, Cl, HCO3). - Fasting serum electrolytes (Na, K, Cl, HCO3) measured on 3 occasions: at baseline, after 4 weeks of drinking blueberry tea, and after 4 weeks of no treatment (randomized cross-over design).
Timepoint [5] 0 0
4 weeks
Secondary outcome [6] 0 0
Improvement in Resting Blood Pressure (central and brachial blood pressure) after 4 weeks of drinking blueberry tea. - Blood Pressure (central and brachial blood pressure) will be measured by Mobil-O-Graph and assessed on 3 occasions: at baseline, after 4 weeks of drinking blueberry tea, and after 4 weeks of no treatment (randomized cross-over design).
Timepoint [6] 0 0
4 weeks
Secondary outcome [7] 0 0
Improvement in resting Augmentation Index after 4 weeks of drinking blueberry tea. - Augmentation index will be measured by Mobil-O-Graph and assessed on 3 occasions: at baseline, after 4 weeks of drinking blueberry tea, and after 4 weeks of no treatment (randomized cross-over design).
Timepoint [7] 0 0
4 weeks
Secondary outcome [8] 0 0
Improvement in large artery stiffness after 4 weeks of drinking blueberry tea. - Large artery stiffness will be measured by Mobil-O-Graph and assessed on 3 occasions: at baseline, after 4 weeks of drinking blueberry tea, and after 4 weeks of no treatment (randomized cross-over design).
Timepoint [8] 0 0
4 weeks

Eligibility
Key inclusion criteria
- Aged 18-75 years.

- Normal to overweight (BMI 19-35 kg/m2).

- On lifestyle or metformin only diabetes treatment.

- Normotensive (seated brachial blood pressure <140/90 mmHg).

- No history of T2D (e.g. fasting plasma glucose <7.0mM); or with clinically diagnosed
T2D on metformin or lifestyle intervention only (e.g. fasting plasma glucose =7.0mM,
HbA1c).

- Willing to drink blueberry tea for 4 weeks (3 times per day with meals).
Minimum age
18 Years
Maximum age
75 Years
Gender
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
- Age <18 yrs or >76 yrs

- Morbidly obese with a BMI =36 kg/m2

- Not on lifestyle and/or metformin only treatment for diabetes (e.g. insulin
injections, sulphonylureas).

- History of myocardial infarction or stroke

- History of malignancy within past 5 years (except for non-melanoma skin cancers)

- Current smoker

- History of severe liver disease

- History of drug or alcohol abuse

- Elective major surgery during the course of the study

- Pregnancy/lactation

- Currently consuming (or have regularly consumed in the past 2 months) blueberry tea,
or supplements containing blueberries, blueberry leaves, raspberry leaves, spearmint
or cinnamon.

- Participation or intention to participate in another clinical research study during
the study period.

- Not willing to consume blueberry tea for 4 weeks.

Study design
Purpose of the study
Treatment
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Crossover
Other design features
Phase
Not Applicable
Type of endpoint(s)
Statistical methods / analysis

Recruitment
Recruitment status
Recruiting
Data analysis
Reason for early stopping/withdrawal
Other reasons
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
TAS
Recruitment hospital [1] 0 0
Menzies Institute for Medical Research - Hobart
Recruitment postcode(s) [1] 0 0
7000 - Hobart

Funding & Sponsors
Primary sponsor type
Other
Name
Menzies Institute for Medical Research
Address
Country

Ethics approval
Ethics application status

Summary
Brief summary
Plant derived compounds, e.g. flavonoids from dark chocolate, green tea, or blueberries, show
great potential as nutraceuticals for the treatment of various diseases such as type 2
diabetes (T2D). Flavonoids have been suggested to improve glucose metabolism, reduce blood
lipids, reduce oxidative stress and improve vascular function. For these reasons we recently
investigated the effects of daily consumption of locally produced blueberry tea and
demonstrated that this could partially restore insulin sensitivity in an animal model. We
propose to translate these findings to assess the efficacy of this nutraceutical as a new
treatment for improving glucose tolerance in people with T2D.
Trial website
https://clinicaltrials.gov/show/NCT02629952
Trial related presentations / publications
DeFuria J, Bennett G, Strissel KJ, Perfield JW 2nd, Milbury PE, Greenberg AS, Obin MS. Dietary blueberry attenuates whole-body insulin resistance in high fat-fed mice by reducing adipocyte death and its inflammatory sequelae. J Nutr. 2009 Aug;139(8):1510-6. doi: 10.3945/jn.109.105155. Epub 2009 Jun 10.
Martineau LC, Couture A, Spoor D, Benhaddou-Andaloussi A, Harris C, Meddah B, Leduc C, Burt A, Vuong T, Mai Le P, Prentki M, Bennett SA, Arnason JT, Haddad PS. Anti-diabetic properties of the Canadian lowbush blueberry Vaccinium angustifolium Ait. Phytomedicine. 2006 Nov;13(9-10):612-23. Epub 2006 Sep 18.
Stull AJ, Cash KC, Johnson WD, Champagne CM, Cefalu WT. Bioactives in blueberries improve insulin sensitivity in obese, insulin-resistant men and women. J Nutr. 2010 Oct;140(10):1764-8. doi: 10.3945/jn.110.125336. Epub 2010 Aug 19.
Couturier K, Batandier C, Awada M, Hininger-Favier I, Canini F, Anderson RA, Leverve X, Roussel AM. Cinnamon improves insulin sensitivity and alters the body composition in an animal model of the metabolic syndrome. Arch Biochem Biophys. 2010 Sep 1;501(1):158-61. doi: 10.1016/j.abb.2010.05.032. Epub 2010 May 31. Review.
Qin B, Nagasaki M, Ren M, Bajotto G, Oshida Y, Sato Y. Cinnamon extract prevents the insulin resistance induced by a high-fructose diet. Horm Metab Res. 2004 Feb;36(2):119-25.
Public notes

Contacts
Principal investigator
Name 0 0
Michelle A Keske, PhD
Address 0 0
Menzies Institute for Medical Research
Country 0 0
Phone 0 0
Fax 0 0
Email 0 0
Contact person for public queries
Name 0 0
Michelle A Keske, PhD
Address 0 0
Country 0 0
Phone 0 0
+61 3 6226 2669
Fax 0 0
Email 0 0
Michelle.Keske@deakin.edu.au
Contact person for scientific queries

Summary results
For IPD and results data, please see https://clinicaltrials.gov/show/NCT02629952