Assessing the effect of anthocyanins through diet and supplementation on cognitive function in older adults at risk for dementia: protocol for a randomised controlled trial

Vinicius do Rosario; Elnaz Lorzadeh; Henry Brodaty; Kaarin J Anstey; Karina Chan; Steven Roodenrys; Katherine Kent; Vida Bliokas; Lyn Phillipson; Katrina Weston-Green; Monique E Francois; Xiaotao Jiang; Jenson George; Jan Potter; Marijka J Batterham; Karen Charlton

doi:10.1136/bmjopen-2024-086435

Assessing the effect of anthocyanins through diet and supplementation on cognitive function in older adults at risk for dementia: protocol for a randomised controlled trial

BMJ Open. 2024 Sep 10;14(9):e086435. doi: 10.1136/bmjopen-2024-086435.

Authors

Vinicius do Rosario¹, Elnaz Lorzadeh¹, Henry Brodaty², Kaarin J Anstey^{3

4}, Karina Chan², Steven Roodenrys⁵, Katherine Kent^{1

6}, Vida Bliokas⁵, Lyn Phillipson⁷, Katrina Weston-Green^{1

8}, Monique E Francois¹, Xiaotao Jiang⁹, Jenson George¹⁰, Jan Potter¹¹, Marijka J Batterham¹², Karen Charlton¹³

Affiliations

¹ School of Medical, Indigenous and Health Sciences, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, New South Wales, Australia.
² Centre for Healthy Brain Ageing, School of Clinical Medicine, Faculty of Medicine and Health, University of New South Wales, Sydney, New South Wales, Australia.
³ Neuroscience Research Australia, University of New South Wales, Sydney, New South Wales, Australia.
⁴ UNSW Ageing Futures Institute, Sydney, New South Wales, Australia.
⁵ School of Psychology, Faculty of Arts and Social Science, University of Wollongong, Wollongong, New South Wales, Australia.
⁶ School of Health Sciences, Western Sydney University, Sydney, New South Wales, Australia.
⁷ School of Health and Society, Faculty of Arts and Social Science, University of Wollongong, Wollongong, New South Wales, Australia.
⁸ Molecular Horizons Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, New South Wales, Australia.
⁹ Microbiome Research Centre (MRC), University of New South Wales, Sydney, New South Wales, Australia.
¹⁰ Department of Agriculture and Fisheries, Queensland Government, Brisbane, Queensland, Australia.
¹¹ Division of Aged Care, Rehabilitation and Palliative Care, Illawarra Shoalhaven Local Health District, Wollongong, New South Wales, Australia.
¹² National Institute for Applied Statistical Research Australia and the Statistical Consulting Centre, School of Mathematics and Applied Statistics, University of Wollongong, Wollongong, New South Wales, Australia.
¹³ School of Medical, Indigenous and Health Sciences, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, New South Wales, Australia karenc@uow.edu.au.

Abstract

Introduction: Promising evidence is emerging for the procognitive, anti-inflammatory and neuroprotective properties of dietary flavonoids, particularly anthocyanins that provide red, purple and blue plant pigments.

Methods and analysis: The 'Food for Thought' study is a multicentre, 6-month randomised, parallel 3-arm clinical trial. Its primary aim is to investigate whether anthocyanin consumption, either through diet or supplementation, can prevent memory loss progression and improve inflammatory and cardiovascular health in older adults at risk for dementia. Eligible participants will include those aged 60-85 years with a diagnosis of amnestic mild cognitive impairment or with a self-referral of memory concerns and scoring ≤13 on the Memory Index Score within the Telephone Montreal Cognitive Assessment screening test. Participants will be randomised to one of three arms: High anthocyanin ('purple foods') diet (aiming for a target of 250 mg anthocyanins/day); freeze-dried product derived from blackcurrants (250 mg anthocyanins/day); or control (coloured maltose powder). The primary outcome is auditory anterograde memory functioning assessed by the Buschke and Grober Free and Cued Selective Reminding Test-Immediate Recall. Secondary outcomes are additional cognitive functions including processing speed, working memory, aspects of executive functioning (attentional shifting and word generativity) and premorbid estimate as well as subjective memory problems and self-reported depression symptoms. Additional secondary outcomes are blood pressure, inflammatory biomarkers, brain-derived neurotrophic factor, fatty acid profile, apolipoprotein E and polyphenol metabolites, gut microbiota composition and function and vascular and microvascular endothelial function tests. Repeated measures analysis of variance and/or mixed linear modelling will evaluate changes over time, with the inclusion of covariates.

Ethics and dissemination: Ethics approval has been obtained from the Greater Western Human Research Ethics Committee (2021/ETH12083). A Consumer Advisory Group was established to guide and review the protocol and dissemination strategy. The results of this trial are intended to be published in a peer-reviewed journal.

Trial sponsor: National Health and Medical Research Centre Dementia Collaborative Research Centre.Start date of clinical trial: 02 September 2022.Expected end date: 11 October 2024.

Trial registration number: ACTRN12622000065796.

Keywords: aging; clinical trial; cognition; dementia; nutrition & dietetics.

Publication types

Clinical Trial Protocol

MeSH terms

Aged
Aged, 80 and over
Anthocyanins* / administration & dosage
Cognition* / drug effects
Cognitive Dysfunction* / prevention & control
Dementia* / prevention & control
Dietary Supplements*
Female
Humans
Male
Middle Aged
Multicenter Studies as Topic
Randomized Controlled Trials as Topic*

Substances

Anthocyanins