Periodontal health, cognitive decline, and dementia: A systematic review and meta-analysis of longitudinal studies.
Level 3 - non-randomized controlled study
Systematic review of non-randomized longitudinal cohort studies
PubMed 36073186 · doi:10.1111/jgs.17978
What was done
Five electronic databases were searched through April 2022 for longitudinal studies assessing the impact of poor periodontal health (periodontitis, tooth loss, deep periodontal pockets, or alveolar bone loss) on cognitive decline and dementia. Random-effects models generated pooled odds ratios (OR) for cognitive decline and hazard ratios (HR) for dementia, with heterogeneity assessed by I2 and evidence quality formally evaluated.
What was found
From 47 included studies (24 for cognitive decline, 23 for dementia): - Poor periodontal health was associated with cognitive decline (OR = 1.23; 95% CI: 1.05–1.44) and dementia (HR = 1.21; 95% CI: 1.07–1.38). - Tooth loss was independently associated with cognitive decline (OR = 1.23; 95% CI: 1.09–1.39) and dementia (HR = 1.13; 95% CI: 1.04–1.23). - Partial tooth loss was associated with cognitive decline (OR = 1.50; 95% CI: 1.02–2.23), and complete tooth loss was associated with dementia (HR = 1.23; 95% CI: 1.05–1.45).
Why it matters
This review synthesizes longitudinal evidence connecting oral disease and tooth loss to long-term neurocognitive decline, highlighting oral health as a potential target in dementia risk research.
Limits
The abstract notes that overall evidence quality was low, methodology across studies lacked robustness, and heterogeneity was present. The associations may be partly driven by reverse causality, where early cognitive impairment leads to neglected oral hygiene. Total individual participant sample size was not reported in the abstract.
Cited by
- supports Oral health is significantly linked to cognitive function.