Association of periodontal condition with cognitive impairment and the mediating role of accelerated biological aging among US older adults

Abstract

AbstractBackgroundIncreasing evidence has shown the associations between periodontitis and cognitive impairment or dementia; however, few studies have explored the role of accelerated biological aging that affects this association. Biological aging is the gradual and progressive decline in system integrity that occurs with advancing age. In this study, we examined the mediating effect of biological aging on the association between periodontal conditions and cognitive impairment in US older adults.MethodWe analyzed data from 2,186 participants aged 60 and older from the US National Health and Nutrition Examination Survey 2011‐2014. Data included sociodemographic, behavioral, and health‐related characteristics, periodontal status (measured by mean clinical attachment loss and pocket depth), blood‐chemistry measures of biological age (using KDM‐biological age and PhenoAge algorithms), and cognitive functioning (measured by Digit Symbol Substitution Test). We created an accelerated biological aging measure using residuals from regressing each blood‐chemistry measure on chronological age. The biological ages’ residual discrepancies with chronological age were defined as the biological age accelerations (BAA). Mediation analysis, weighted for complex survey design, assessed the effect of BAA on the association between periodontal conditions and cognitive functioning.ResultAfter adjusting for covariates, participants with periodontitis exhibited greater KDM BAA (β [SE] = ‐0.40 [0.17]), PhenoAge BAA (β [SE] = ‐0.57 [0.21]), and lower level of cognitive function (β [SE] = ‐1.50 [0.33]) than those without periodontitis. Both KDM and PhenoAge BAA were significantly associated with lower cognitive functioning (β [SE] = ‐0.27 [0.10] and β [SE] = ‐0.29 [0.07]), mediating 11.0% and 9.7% of the total effects of periodontitis on cognitive functioning, respectively. Furthermore, KDM and PhenoAge BAA mediated 11.7% and 5.8% of the association between mean pocket depth and DSST, respectively.ConclusionOur findings suggest that periodontitis is partially associated with worse cognitive functioning through accelerating the biological aging process. Efforts to improve oral health or slow biological aging have the potential to help reserve cognitive health in later life.