Oral Health, Periodontal Status, and Cognitive Function in Middle-Aged and Older Adults: A Cross-Sectional Analytical Pilot Study

Background: Cognitive aging is a physiological process that involves gradual and mild changes in mental functions. When these changes significantly affect cognitive performance, it is considered cognitive decline. Objective: This analytical cross-sectional pilot study examined the association between periodontal status, systemic conditions, and cognitive performance in middle-aged and older adults. Methods: Forty adults aged 35–59 years (n = 20) and ≥60 years (n = 20) from northeastern Mexico were evaluated. Oral assessments included the Modified Gingival Index and detection of Porphyromonas gingivalis and Fusobacterium nucleatum using qPCR. Cognitive function was evaluated with the Mini-Mental State Examination (MMSE), and frailty with the Clinical Frailty Scale (CFS) and Oral Frailty Checklist (OF-5). Systemic medical history and oral hygiene habits were determined using a questionnaire. Results: MMSE scores were lower in older adults compared with middle-aged adults, and the magnitude of the difference was small. The presence of P. gingivalis or F. nucleatum was similar between groups. Frailty indicators were more prevalent in older adults. Logistic regression identified age and frailty-related variables as the strongest predictors of lower cognitive performance, whereas microbiological findings were not significant predictors. Conclusions: Age and frailty indicators, rather than bacterial presence alone, were associated with reduced cognitive performance in this pilot sample. Although no microbiological differences were observed, the findings highlight the need for larger analytical studies incorporating quantitative bacterial load and additional confounders to better understand the oral–systemic–cognitive interactions.