Randomised controlled trial of the effects of kefir on behaviour, sleep and the microbiome in children with ADHD: a study protocol

Lawrence, Kate; Fibert, Philippa; Hobbs, Jemima; Myrissa, Kyriaki; Toribio-Mateas, Miguel A; Quadt, Frits; Cotter, Paul D. and Gregory, Alice M.. 2023. Randomised controlled trial of the effects of kefir on behaviour, sleep and the microbiome in children with ADHD: a study protocol. BMJ Open, 13, e071063. ISSN 2044-6055 [Article]

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Abstract or Description

Introduction Current interventions for children with attention-deficit/hyperactivity disorder (ADHD) are primarily medication, behavioural therapy and parent training. However, research suggests dietary manipulations may provide therapeutic benefit for some. There is accumulating evidence that the gut microbiome may be atypical in ADHD, and therefore, manipulating gut bacteria in such individuals may help alleviate some of the symptoms of this condition. The aim of this study is to explore the effects of supplementation with kefir (a fermented dairy drink) on ADHD symptomatology, sleep, attention and the gut microbiome in children diagnosed with ADHD.

Methods and analysis A 6-week randomised, double-blind, placebo-controlled trial in 70 children aged 8–13 years diagnosed with ADHD. Participants will be recruited throughout the UK, through support groups, community groups, schools, social media and word of mouth. Children will be randomised to consume daily either dairy kefir or a placebo dairy drink for 6 weeks. The primary outcome, ADHD symptomatology, will be measured by The Strengths and Weakness of ADHD-symptoms and Normal-behaviour scale. Secondary outcomes will include gut microbiota composition (using shotgun metagenomic microbiome sequencing), gut symptomatology (The Gastrointestinal Severity Index questionnaire), sleep (using 7-day actigraphy recordings, The Child’s Sleep Habits Questionnaire and Sleep Self Report questionnaire), inattention and impulsivity (with a computerised Go/NoGo test). Assessments will be conducted prior to the intervention and at the end of the intervention. Interaction between time (preintervention/postintervention) and group (probiotic/placebo) is to be analysed using a Mixed Model Analysis of Variances.

Ethics and dissemination Ethical approval for the study was granted by St Mary’s University Ethics Committee. Results will be disseminated through peer-reviewed publications, presentations to the scientific community and support groups.

Trial registration number NCT05155696.

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This research and the APC was supported by Child Development Fund Research Grants from The Waterloo Foundation, (grant numbers: 1961/3248, 1961/4748).

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7 November 2023Accepted
7 December 2023Published

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Date Deposited:

08 Nov 2023 09:26

Last Modified:

05 Jan 2024 12:27

Peer Reviewed:

Yes, this version has been peer-reviewed.



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