ANZCTR - Registration

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Trial registered on ANZCTR

Registration number

ACTRN12615001294549

Ethics application status

Approved

Date submitted

16/11/2015

Date registered

27/11/2015

Date last updated

5/02/2018

Type of registration

Prospectively registered

Titles & IDs

Public title

Does 12 weeks of eating different snack foods improve cognitive performance and cardiometabolic health in adults?

Scientific title

Does 12 weeks of eating a habitual diet including almonds, compared with a habitual nut-free diet, affect cognitive performance and cardiometabolic health in healthy overweight adults?

Secondary ID [1]

Nil

Universal Trial Number (UTN)

Trial acronym

Linked study record

Health condition

Health condition(s) or problem(s) studied:

Cognitive performance

Vascular function

Cardiometabolic health

Condition category

Condition code

Cardiovascular

Normal development and function of the cardiovascular system

Diet and Nutrition

Other diet and nutrition disorders

Mental Health

Studies of normal psychology, cognitive function and behaviour

Intervention/exposure

Study type

Interventional

Description of intervention(s) / exposure

12-week randomized, controlled, parallel-arm study that investigates the effects of daily unsalted almond consumption on cognitive function and established and emerging cardiometabolic biomarkers of disease in healthy participants in a free-living environment. Participants will be randomly allocated to consuming unsalted almonds (at 15% of energy intake) in conjunction with their habitual diet for 12 weeks. Overall calorie intake will remain the same as their habitual diet so participants will be advised by a dietitian on how to substitute foods to maintain the equivalent energy intake. Test foods can be eaten at any time of the day as decided by the participant. Test food checklists, serum and erythrocyte alpha-tocopherol (Vitamin E) levels will used to assess compliance.

Intervention code [1]

Lifestyle

Comparator / control treatment

12-week randomized, controlled, parallel-arm study that investigates the effects of daily unsalted almond consumption on cognitive function and established and emerging cardiometabolic biomarkers of disease in healthy participants in a free-living environment. Participants will be randomly allocated to consuming an isocaloric snack food (at 15% of energy intake) in conjunction with their habitual diet for 12 weeks. The control snack foods will contain an equal amount of energy and will be provided by the study. Participants' overall calorie intake will remain the same as their habitual diet so participants will be advised by a Dietitian on how to substitute foods to maintain the equivalent energy intake. Test food checklists will used to assess compliance. Participants will be advised to avoid nuts, including nuts as snacks, ingredients in a recipe (either as whole or ground nuts) or in packaged products more than or equal to 5% nuts as listed in the ingredients. All participants will have a 2 week period prior to stating the trial where they do not eat nuts or nut products.

Control group

Active

Outcomes

Primary outcome [1]

Change in the the composite scores for the cognitive domain, Attention, from baseline to the end of the dietary phase in each group will be assessed and the change scores compared between groups. The Attention domain will be assessed by the following tasks : Simple Reaction Time, Choice Reaction Time, Four-Choice Reaction Time, Rapid Visual Information Processing (RVIP) task and Serial Subtractions.

Timepoint [1]

Baseline and after completion of 12 weeks dietary intervention

Primary outcome [2]

Change in the the composite scores for the cognitive domain, Working Memory, from baseline to the end of the dietary phase in each group will be assessed and the change scores compared between groups. Participants' Working Memory will be assessed by the following tasks : Numerical Working Memory, N-back, Corsi blocks, Serial Subtraction and Rapid Visual Information Processing.

Timepoint [2]

Baseline and after completion of 12 weeks dietary intervention

Primary outcome [3]

Change in the the composite scores for the cognitive domain, Long term Memory, from baseline to the end of the dietary phase in each group will be assessed and the change scores compared between groups. Participants' Long Term Memory will be assessed by the following tasks : Word Recall, Word Recognition, Picture Recognition and Verbal Fluency.

Timepoint [3]

Baseline and at the completion of 12 weeks dietary intervention

Secondary outcome [1]

Change in body weight/composition (% fat), waist circumference and body mass index from baseline to the end of 12 weeks of either consuming a habitual diet with almonds incorporated or 12 weeks of a habitual nut-free diet.

Timepoint [1]

Baseline and after completion of 12 weeks dietary intervention

Secondary outcome [2]

Change in glucose metabolism; fasting plasma glucose and insulin from baseline to the end of 12 weeks of either consuming a habitual diet with almonds incorporated or 12 weeks of a habitual nut-free diet.

Timepoint [2]

Baseline and after completion of 12 weeks dietary intervention

Secondary outcome [3]

Change in lipid metabolism; fasting blood lipids (Cholesterol, HDL, triglycerides) from baseline to the end of 12 weeks of either consuming a habitual diet with almonds incorporated or 12 weeks of a habitual nut-free diet.

Timepoint [3]

Baseline and after completion of 12 weeks dietary intervention

Secondary outcome [4]

Change in vascular measures; supine blood pressure and arterial compliance of large and small arteries from baseline to the end of 12 weeks of either consuming a habitual diet with almonds incorporated or 12 weeks of a habitual nut-free diet.

Timepoint [4]

Baseline and after completion of 12 weeks dietary intervention

Secondary outcome [5]

Change in serum levels of the inflammatory marker; plasma C-reactive protein, from baseline to the end of 12 weeks of either consuming a habitual diet with almonds incorporated or 12 weeks of a habitual nut-free diet.

Timepoint [5]

Baseline and after completion of 12 weeks dietary intervention

Secondary outcome [6]

Change in urinary markers of oxidative stress and blood a-tocopherol as a measure of compliance to eating almonds from baseline to the end of 12 weeks of either consuming a habitual diet with almonds incorporated or 12 weeks of a habitual nut-free diet. ..

Timepoint [6]

Baseline and after completion of 12 weeks dietary intervention

Secondary outcome [7]

Primary Outcome: Change in the the composite scores for the cognitive domain, Executive Function, from baseline to the end of the dietary phase in each group will be assessed and the change scores compared between groups. The Executive Function domain will be assessed by the following tasks: Stroop, Verbal Fluency, Serial Subtraction and Peg and Ball.

Timepoint [7]

Baseline and at the completion of 12 weeks dietary intervention

Secondary outcome [8]

Primary Outcome: Change in the the scores for the cognitive test, Numerical Working Memory, from baseline to the end of the dietary phase in each group will be assessed and the change scores compared between groups.

Timepoint [8]

Baseline and at the completion of 12 weeks dietary intervention

Secondary outcome [9]

Primary Outcome: Change in the the scores for the cognitive test, Immediate Word Recall, from baseline to the end of the dietary phase in each group will be assessed and the change scores compared between groups.

Timepoint [9]

Baseline and at the completion of 12 weeks dietary intervention

Secondary outcome [10]

Primary Outcome: Change in the the scores for the cognitive test, Simple Reaction Time, from baseline to the end of the dietary phase in each group will be assessed and the change scores compared between groups.

Timepoint [10]

Baseline and at the completion of 12 weeks dietary intervention

Secondary outcome [11]

Primary Outcome: Change in the the scores for the cognitive test, Choice reaction Time, from baseline to the end of the dietary phase in each group will be assessed and the change scores compared between groups.

Timepoint [11]

Baseline and at the completion of 12 weeks dietary intervention

Secondary outcome [12]

Primary Outcome: Change in the the scores for the cognitive test, Four Choice Reaction Time, from baseline to the end of the dietary phase in each group will be assessed and the change scores compared between groups.

Timepoint [12]

Baseline and at the completion of 12 weeks dietary intervention

Secondary outcome [13]

Primary Outcome: Change in the the scores for the cognitive test, Rapid Visual Information Processing task, from baseline to the end of the dietary phase in each group will be assessed and the change scores compared between groups.

Timepoint [13]

Baseline and at the completion of 12 weeks dietary intervention

Secondary outcome [14]

Primary Outcome: Change in the the scores for the cognitive test, N-back, from baseline to the end of the dietary phase in each group will be assessed and the change scores compared between groups.

Timepoint [14]

Baseline and at the completion of 12 weeks dietary intervention

Secondary outcome [15]

Primary Outcome: Change in the the scores for the cognitive test, Corsi Blocks, from baseline to the end of the dietary phase in each group will be assessed and the change scores compared between groups.

Timepoint [15]

Baseline and at the completion of 12 weeks dietary intervention

Secondary outcome [16]

Primary Outcome: Change in the the scores for the cognitive test, Delayed Word Recall, from baseline to the end of the dietary phase in each group will be assessed and the change scores compared between groups.

Timepoint [16]

Baseline and at the completion of 12 weeks dietary intervention

Secondary outcome [17]

Primary Outcome: Change in the the scores for the cognitive test, Delayed Word Recognition, from baseline to the end of the dietary phase in each group will be assessed and the change scores compared between groups.

Timepoint [17]

Baseline and at the completion of 12 weeks dietary intervention

Secondary outcome [18]

Primary Outcome: Change in the the scores for the cognitive test, Delayed Picture Recognition, from baseline to the end of the dietary phase in each group will be assessed and the change scores compared between groups.

Timepoint [18]

Baseline and at the completion of 12 weeks dietary intervention

Secondary outcome [19]

Primary Outcome: Change in the the scores for the cognitive test, Serial Subtractions, from baseline to the end of the dietary phase in each group will be assessed and the change scores compared between groups.

Timepoint [19]

Baseline and at the completion of 12 weeks dietary intervention

Secondary outcome [20]

Primary Outcome: Change in the the scores for the cognitive test, Verbal Fluency, from baseline to the end of the dietary phase in each group will be assessed and the change scores compared between groups.

Timepoint [20]

Baseline and at the completion of 12 weeks dietary intervention

Secondary outcome [21]

Primary Outcome: Change in the the scores for the cognitive test, Excluded Letter Task, from baseline to the end of the dietary phase in each group will be assessed and the change scores compared between groups.

Timepoint [21]

Baseline and at the completion of 12 weeks dietary intervention

Secondary outcome [22]

Primary Outcome: Change in the the scores for the cognitive test, Stroop, from baseline to the end of the dietary phase in each group will be assessed and the change scores compared between groups.

Timepoint [22]

Baseline and at the completion of 12 weeks dietary intervention

Secondary outcome [23]

Primary Outcome: Change in the the scores for the cognitive test, Peg and Ball, from baseline to the end of the dietary phase in each group will be assessed and the change scores compared between groups.

Timepoint [23]

Baseline and at the completion of 12 weeks dietary intervention

Secondary outcome [24]

Change in the serum levels of the protein, Vascular Cell Adhesion Molecule, from baseline to the end of 12 weeks of either consuming a habitual diet with almonds incorporated or 12 weeks of a habitual nut-free diet.

Timepoint [24]

Baseline and at the completion of 12 weeks dietary intervention

Secondary outcome [25]

Change in the serum levels of the protein, Intrercellular Cell Adhesion Molecule, from baseline to the end of 12 weeks of either consuming a habitual diet with almonds incorporated or 12 weeks of a habitual nut-free diet.

Timepoint [25]

Baseline and at the completion of 12 weeks dietary intervention

Eligibility

Key inclusion criteria

Overweight healthy adults with BMI between 25-39.9 kg/m2. Non-smokers.
Weight stable in the past 3 months. No diagnosis of cognitive impairment or memory loss or a Montreal Cognitive Assessment (MoCA) score of >18. Non-restrained eaters. No allergies or food intolerances to nuts or ingredients in control foods.

Minimum age

50 Years

Maximum age

80 Years

Sex

Both males and females

Can healthy volunteers participate?

Yes

Key exclusion criteria

Have a BP of > 160/100 mmHg. Regularly consume large amounts of nuts or nut butters (more than 210 g per week). Have cardiovascular disease (including uncontrolled high blood pressure) and chronic diseases including Type 1 and 2 diabetes. Has a history of depression in the prior 2 years or Geriatric Depression Score (GDS)-15 score of more than 10. Has any neurological disorder, including but not limited to, Alzheimer’s disease, Parkinson’s disease, stroke, intracranial haemorrhage and brain lesions including tumours. Has a recent history (within 12 months) or strong potential for alcohol abuse. Defined as >14 standard drinks per week. Are colour blind. Have changed medications in the last 3 months. Take medications or supplements that may have an impact on the study outcomes. Have a history of infective or inflammatory brain disease or head injury. Are planning on dieting to control weight during the study. Are already involved in a research study that may influence the outcomes of this study within 30 days of commencing present study. Are pregnant or breast feeding.

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)

A randomisation schedule will be generated by a random number generator which will match participant identification numbers to a treatment arm. An independent holder of the randomisation schedule will perform treatment allocation without contact with the volunteers.

Methods used to generate the sequence in which subjects will be randomised (sequence generation)

Groups will be allocated to treatment using the process of randomization by minimization to ensure matching based on age, gender and body mass index.

Masking / blinding

Blinded (masking used)

Who is / are masked / blinded?

The people assessing the outcomes
The people analysing the results/data

Intervention assignment

Parallel

Other design features

Phase

Not Applicable

Type of endpoint/s

Efficacy

Statistical methods / analysis

Baseline characteristics between the treatment groups will be compared using one-way ANOVA. The effects of almonds and control foods on the dependent measures over time will be analyzed using random effects mixed models, with treatment (almond group or control group) and time being the factors in the analysis and time being the repeated measurement. For significant interactions, Bonferroni post hoc pairwise comparisons will be performed to identify differences between means. Statistical significance will be set at P<0.05. Primary outcomes for this trial include composite scores for different cognitive domains and also individual cognitive tests. The composite score of speed of memory is known to decline with age and was susceptible to an omega-3 intervention in a healthy cohort. Additionally, the domain of speed of memory incorporates elements of processing speed which was improved by a nut intervention in a previous study by the team. Power analysis indicated that a total of 68 participants per group will be required to detect a difference in cognitive function between the two groups that equates to a medium effect size (0.5), at an -level of 0.05 with a statistical power of 0.80. An additional 7 subjects per group (10%) will be recruited to allow for attrition. Hence, we will recruit 150 participants in total. Based on previous published studies with similar populations and other nuts, we anticipate having sufficient power for secondary outcomes also.

Recruitment

Recruitment status

Completed

Date of first participant enrolment

Anticipated

1/02/2016

Actual

27/01/2016

Date of last participant enrolment

Anticipated

1/08/2017

Actual

29/09/2017

Date of last data collection

Anticipated

Actual

15/12/2017

Sample size

Target

150

Accrual to date

Final

151

Recruitment in Australia

Recruitment state(s)

Funding & Sponsors

Funding source category [1]

Commercial sector/Industry

Name [1]

The Almond Board of California

Address [1]

1150 Ninth St
Suite 1500
Modesto, CA, 95354

Country [1]

United States of America

Primary sponsor type

Individual

Name

Assoc.Prof Alison Coates

Address

University of South Australia
Alliance for Research in Exercise, Nutrition and Activity (ARENA)
Postal address: GPO Box 2471, Adelaide SOUTH AUSTRALIA 5001.

Country

Australia

Secondary sponsor category [1]

Individual

Name [1]

Prof. Jon Buckley

Address [1]

University of South Australia
Alliance for Research in Exercise, Nutrition and Activity (ARENA)
Postal address: GPO Box 2471, Adelaide SOUTH AUSTRALIA 5001.

Country [1]

Australia

Secondary sponsor category [2]

Individual

Name [2]

Prof. Andrew Scholey

Address [2]

Centre for Human Psychopharmacology
Swinburne University
Melbourne VIC 3122
Australia

Country [2]

Australia

Secondary sponsor category [3]

Individual

Name [3]

Dr Alison Hill

Address [3]

University of South Australia
Alliance for Research in Exercise, Nutrition and Activity (ARENA)
Postal address: GPO Box 2471, Adelaide SOUTH AUSTRALIA 5001.

Country [3]

Australia

Ethics approval

Ethics application status

Approved

Ethics committee name [1]

University of South Australia Human Ethics Committee

Ethics committee address [1]

Research and Innovation Services
Mawson Lakes Campus
University of South Australia
PO Box 2471
Adelaide,
South Australia 5001
Australia.

Ethics committee country [1]

Australia

Date submitted for ethics approval [1]

09/06/2015

Approval date [1]

08/10/2015

Ethics approval number [1]

0000034452

Summary

Brief summary

The primary aim of this study is to investigate the effects of eating unsalted almonds on major cognitive domains (attention/concentration, executive function, working memory, secondary memory, spatial memory) and the secondary aims are to explore potential cardiovascular, metabolic and inflammatory mechanisms underpinning cognitive enhancement following 12 weeks of almond consumption.This study will be a 12 week
randomized, controlled, parallel arm study that investigates the effects of unsalted almond consumption or alternative snack food (at 15% of energy intake) on cognitive function and established and emerging cardiometabolic biomarkers of disease in healthy participants in a free living environment. Participants will be asked to continue with their usual lifestyle whilst avoiding consumption of other nuts or nut butters apart from study foods. At the start of the study and after 12 weeks of eating almonds or the alternate snack food we will examine cognitive function in a computerised cognitive test battery, as well as cardiometabolic biomarkers (lipids, glucose regulation), vascular function (blood pressure, arterial compliance, circulating adhesion molecules) and markers of systemic inflammation.

Trial website

N/A

Trial related presentations / publications

N/A

Public notes

N/A

Contacts

Principal investigator

Name

A/Prof Alison Coates

Address

University of South Australia
School of Health Sciences
Alliance for Research in Exercise, Nutrition and Activity (ARENA)
Postal address: GPO Box 2471, Adelaide SOUTH AUSTRALIA 5001.

Country

Australia

Phone

+61 8 83022313

Fax

[email protected]

Contact person for public queries

Name

Dr Catherine Yandell

Address

University of South Australia
School of Health Sciences
Alliance for Research in Exercise, Nutrition and Activity (ARENA)
Postal address: GPO Box 2471, Adelaide SOUTH AUSTRALIA 5001.

Country

Australia

Phone

+61 8 83022109

Fax

[email protected]

Contact person for scientific queries

Name

A/Prof Alison Coates

Address

University of South Australia
School of Health Sciences
Alliance for Research in Exercise, Nutrition and Activity (ARENA)
Postal address: GPO Box 2471, Adelaide SOUTH AUSTRALIA 5001.

Country

Australia

Phone

+61 8 83022313

Fax

[email protected]

No information has been provided regarding IPD availability

What supporting documents are/will be available?

No Supporting Document Provided

Results publications and other study-related documents

Documents added manually

No documents have been uploaded by study researchers.

Documents added automatically

Source	Title	Year of Publication	DOI
Embase	Minimal changes in telomere length after a 12-week dietary intervention with almonds in mid-age to older, overweight and obese Australians: Results of a randomised clinical trial.	2022	https://dx.doi.org/10.1017/S0007114521001549
Embase	Application of an Australian dietary guideline index to weighed food records.	2019	https://dx.doi.org/10.3390/nu11061286

N.B. These documents automatically identified may not have been verified by the study sponsor.

Trial Review

Documents added manually

Documents added automatically