Effects of oral health intervention strategies on cognition and microbiota alterations in patients with mild Alzheimer's disease: A randomized controlled trial.

We explored the effects of an oral health intervention on the oral microbiome and cognitive function of patients with mild Alzheimer's disease (AD) and determined the influence on disease progression. Sixty-six patients with mild AD were randomly assigned to intervention or control groups and received a 24-week oral health intervention and routine care, respectively. Data were collected at baseline and week 24. 16 S rRNA sequencing was used to analyze oral microbiota. After 24 weeks of oral health intervention, Kayser-Jones Brief Oral Health Status Examination (BOHSE), Mini-Mental State Examination (MMSE), Neuropsychiatric Inventory (NPI), Nursing Home Adjustment Scale (NHAS), and Alzheimer's Disease Cooperative Study-ADL (ADCS-ADL) scores were different between groups (p < 0.05). Subgingival plaque in patients with AD showed significant differences in the diversity and abundance of oral microbiomes, with a higher abundance of normal oral flora in the intervention group. We found oral health intervention strategies are effective in modifying subgingival microbiota differences and slowing cognitive decline in mild AD patients.