(P22-008-23) Protocol for an Observational Study of Microbiome Profiles, Sleep, and Cognition Among Latinx Midlife Adults

Objectives: Growing evidence suggests that sleep disturbance, a risk factor for the development of Alzheimer’s disease (AD) is linked to changes in the gut microbiome in a bidirectional manner. Nutrient ingestion and diet quality play a role in both gut microbe composition and sleep regulation, implying a link between diet, gut microbiome, and sleep. Limited research on Latinx adults has found a unique gut microbial profile for this population. We seek to expand existing findings by incorporating diet quality assessments, cognitive measures, cortisol sampling, and objective sleep measures, as an innovative way to explore the possible correlations among these factors. This study aims to examine the impact of sleep behaviors on cognition while accounting for dietary intake and gut microbiome composition in a midlife Latinx community-based sample and examine socio-cultural factors at various levels of influence that may impact diet, sleep, cognition, and gut microbes.

Methods: This study will utilize staggered recruitment and existing resources to seek the participation of 150 Latinx midlife adults over time. Each participant will be given a battery of neurocognitive and sleep assessments and provide saliva samples to assess salivary cortisol, and a stool sample to examine and characterize the gut microbiome via whole-genome shotgun sequencing. Fecal samples will be self-collected by participants using the OMNIgene-GUT kit. Considering the role of dietary intake on gut microbial composition, three detailed 24-hour recalls using the Automated Self-Administered Recall System (ASA24) will be collected. Diet quality will then be evaluated using the Healthy Eating Index (HEI) to determine how closely intake adheres to the Dietary Guidelines for Americans.

Results: PROTOCOL ABSTRACT

Conclusions: In community-based samples, studies focusing on the microbiota-gut-brain axis are crucial to identifying modifiable risk factors for cognitive decline and guiding innovative therapies. The findings of this study will yield indispensable data to recognize the influence of diet quality and gut microbiota on cognition and sleep. Changes in sleep patterns and ingestion of nutrients could affect gut microbial composition and diversity, impacting circadian rhythms and hormones that regulate sleep and waking and eventually impacting AD risk.

Funding Sources: NIMHD 2U54MD012393