Beyond the Pillow: Linking Subjective and Objective Sleep Measures to Gut Microbiome Composition in Community-Dwelling Older Adults.

Background: Sleep-related complaints are common among older adults, and recent research indicates that changes in sleep patterns may be associated with alterations in the composition of the gut microbiome (GM). However, investigations into the relationship between sleep measures and GM abundance among older adults have been limited thus far. This study represents the first large-scale effort to comprehensively explore the connection between GM composition and both subjective and objective sleep measures in older adults. Methods: The study included 279 cognitively-normal older adults from the community who had not used sleep medication, antibiotics, or probiotics for at least one month before providing stool samples. Participants were categorized as good sleepers (GS) or poor sleepers (PS) based on the Pittsburgh Sleep Quality Index (PSQI) scores. GM diversity and relative abundance were compared between both groups, and their associations with PSQI scores and objective sleep measures were also examined. Results: Alpha and beta diversity did not show significant differences between the GS and PS groups. However, significant differences in GM relative abundance across various taxonomic levels were found between the GS and PS groups. In the overall sample, higher PSQI scores were linked to lower abundance of the species Hungatella_hathewayi (p = 0.005, false discovery rate = 0.035). However, there were no significant associations between GM abundance and objective sleep measures after corrections for multiple comparisons. Conclusion: These findings suggest that specific gut microbial taxa are associated with subjective sleep disturbances in older adults.