Oral microbiota profile is related to cognitive status in centenarians: a clinical and biological study

Objectives: A growing body of evidence supports the potential role of the oral microbiota in influencing cognitive function. Centenarians, at the extreme end of the lifespan, are the ideal cohort to study the long-term effects of inflammaging. Study design: Twenty-three centenarians were examined by a neurologist, neuropsychologist and dentist to assess cognitive status and oral health. They were also profiled for oral microbiota and inflammasome. Results: We found less alpha diversity in the oral microbiota of participants with dementia and an overall depletion of typical oral commensals, including Alloprevotella, Prevotella, Veillonella, Fusobacterium and Leptotrichia. The latter two were also underrepresented in edentulous compared with dentate subjects. Moreover, levels of pro-inflammatory cytokines and chemokines tended to be higher in participants with dementia. Conclusions: Our data support a relationship between oral microbiota, cognitive status and inflammation, which deserves further exploration to counteract cognitive decline while promoting healthy aging.