Association between poor periodontal health and 15‐year risk of incident dementia

Abstract

AbstractBackgroundPoor oral health, particularly tooth loss, has been highlighted as a potential modifiable risk factor for dementia. However, longitudinal evidence concerning the association of poor periodontal health with dementia is limited. This study examines the impact of poor periodontal health on 15‐year risk of incident dementia.MethodThis study included 4596 dementia‐free and dentate (i.e., having ≥1 teeth remaining) participants, aged 30‐93 years, from population‐based Finnish Health 2000 Survey. Periodontal health at baseline was evaluated through bleeding on probing (BOP), periodontal pocket depths (PPD), and alveolar bone loss (ABL). BOP for each sextant and PPD for each tooth (excluding third molars and residual roots) were recorded clinically during oral examination. Based on BOP, participants were dichotomized into having ≥1 sextant with BOP versus no BOP.Tooth with PPD of ≥4mm was considered as having deepened periodontal pocket. Based on PPD, participants were dichotomized into having ≥1 teeth with deepened PPD versus no PPD. ABL for each tooth was examined through orthopantomographs and defined as vertical bone loss extending apically to at least the middle third of tooth root. Based on ABL, participants were dichotomized into having ≥1 teeth with ABL versus no ABL. Dementia diagnosis until 2015 was retrieved from national health registers.Cox proportional regression was conducted and adjusted for age, gender, education, cardiovascular risk, socioeconomic status, depression, alcohol consumption, c‐reactive protein, and overall tooth count. Sensitivity analysis accounting for potential reverse causality bias was conducted by excluding incident dementia during the first five years of follow‐up.Result183 participants developed dementia over 15 years. Fully adjusted hazard ratio among participants with ≥1 sextant with BOP was 1.15 (CI:0.80‐1.65), with ≥1 teeth having deepened PPD was 0.94 (CI:0.67–1.31), and with ≥1 teeth having ABL was 0.97 (CI:0.64–1.49). Findings from sensitivity analysis for potential reverse causality bias corroborated with results for main analyses.ConclusionPreliminary findings indicate no association of BOP, PPD, or ABL with 15‐year dementia risk. However, further well‐designed longitudinal studies with more comprehensive periodontal assessment (e.g., clinically diagnosed periodontitis and severity of periodontitis) are warranted to conclusively assess its impact on dementia risk.