3rd Edition of Dementia World Conference 2026

Abstract

Alzheimer’s disease (AD) is characterized by progressive cognitive impairment, neuropsychiatric manifestations such as depression, and emerging evidence of gut microbiome dysregulation. Yoga has been shown to improve cognitive and emotional well-being and may influence the gut–brain axis; however, integrated clinical and metagenomic evidence in AD remains scarce.

Objective:
To evaluate the impact of a 12-week structured yoga intervention on cognitive performance, depressive symptoms, and gut microbial diversity, composition, and functional pathways in Indian patients with mild AD.

Methods:
In this hospital-based exploratory case–control study, 16 patients with mild AD and 17 cognitively healthy controls (HCs) were recruited at AIIMS, New Delhi. AD diagnosis was established according to NIA-AA criteria and supported by Montreal Cognitive Assessment (MoCA) and Patient Health Questionnaire-9 (PHQ-9) scores. Patients with AD participated in supervised 60-minute daily yoga sessions for 12 weeks. Cognitive function, depressive symptoms, and stool samples were assessed at baseline and post-intervention. Shotgun metagenomic sequencing was performed for taxonomic and functional profiling. Microbial alpha diversity, beta diversity (Bray–Curtis dissimilarity), and differential abundance analyses were conducted using standard bioinformatics pipelines.

Results:
Post-intervention, AD participants showed significant improvement in cognitive function (MoCA: 22.33 ± 2.34 to 25.44 ± 2.01; p = 0.001) and a marked reduction in depressive symptoms (PHQ-9: 5.78 ± 3.11 to 2.22 ± 1.71; p = 0.007). Although alpha diversity remained unchanged, beta diversity analyses demonstrated a significant post-yoga shift of the AD gut microbiome toward the HC microbial profile. This shift was characterized by increased abundance of beneficial taxa, including Faecalibacterium prausnitzii, Roseburia intestinalis, Bifidobacterium, and Akkermansia, alongside reduced levels of pro-inflammatory taxa such as Collinsella aerofaciens and Klebsiella spp. Functional pathway analysis indicated partial restoration of metabolic and short-chain fatty acid–associated pathways.

Conclusions:
A 12-week yoga intervention was associated with improved cognition, reduced depressive symptoms, and partial normalization of gut microbial composition and function in patients with mild AD. These findings support the potential of yoga as an adjunct lifestyle intervention targeting the gut–brain axis in AD. Larger randomized controlled trials integrating lifestyle monitoring and multi-omics approaches are warranted to confirm these observations and clarify underlying mechanisms.

Keywords:
Alzheimer’s disease; yoga intervention; gut microbiome; cognitive function; depressive symptoms; metagenomics; short-chain fatty acids; microbiome diversity; neurodegeneration; gut–brain axis