Journal of the American Medical Directors Association
Review ArticleDose-Response Meta-Analysis on Tooth Loss With the Risk of Cognitive Impairment and Dementia
Section snippets
Protocol and Registration
This meta-analysis protocol was registered in the National Institute for Health Research, International Prospective Register of Systematic Reviews (PROSPERO, registration number: CRD42019128023). The reporting of this study was in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Guideline (Supplementary Material 1).20
Search Strategy
We searched 6 databases, including PubMed/MEDLINE, Medline (Ovid), EMBASE (Ovid), CINAHL (EBSCO), Web of Science, and Cochrane Library
Literature Search
Fourteen studies were identified in this review. The study selection process and the literature search results are depicted in Supplementary Material 3. Among the 14 articles, 3 articles conducted separate analyses on either education level (higher and lower),26 cognitive function (cognitive impairment and dementia),27 or gender (male and female);28 therefore, the final meta-analysis contained 17 datasets. Eight studies were included in the dose-response analysis.27, 28, 29, 30, 31, 32, 33, 34
Assessment of Tooth Loss
Discussion
This meta-analysis revealed the association between tooth loss and risk of cognitive impairment and dementia based on 14 longitudinal studies containing 34,074 participants and 4689 cases with diminished cognitive function. Our results indicated that more tooth loss increased the risk of cognitive impairment by 1.48 times and dementia by 1.28 times, even after controlling for a range of potential confounders. A further dose-response analysis detected linear associations between tooth loss and
Conclusions and Implications
In summary, this study provided further support of tooth loss as a risk factor for cognitive impairment and dementia. Furthermore, this review highlights that maintaining good oral health may help preserve cognitive function. The findings also indicate that timely prosthodontic treatment may slow the progression of cognitive decline. In clinical practice, health professionals can play an important role in educating patients and family members on the importance of improving oral health.
Author Contributions
Xiang Qi had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis. Concept and design: Bei Wu. Acquisition, analysis, and interpretation of data: Xiang Qi and Zheng Zhu. Drafting of the manuscript: Xiang Qi. Critical revision of the manuscript for important intellectual content: Brenda L. Plassman, Bei Wu. Statistical analysis: Xiang Qi. Obtained funding: Bei Wu. Supervision: Bei Wu.
References (57)
- et al.
Racial and ethnic estimates of Alzheimer’s disease and related dementias in the United States (2015–2060) in adults aged ≥65 years
Alzheimers Dement
(2019) - et al.
Potentially modifiable risk factors for dementia in identical twins
Alzheimers Dement
(2006) - et al.
Twenty-year trends in dependency in residential aged care in Auckland, New Zealand: A descriptive study
J Am Med Dir Assoc
(2011) - et al.
Tooth loss is associated with increased risk of dementia and with a dose-response relationship
Front Aging Neurosci
(2018) - et al.
Tooth loss is associated with accelerated cognitive decline and volumetric brain differences: A population-based study
Neurobiol Aging
(2018) - et al.
Oral disease in relation to future risk of dementia and cognitive decline: Prospective cohort study based on the action in diabetes and vascular disease: Preterax and Diamicron Modified-Release Controlled Evaluation (Advance) Trial
Eur Psychiatry
(2013) - et al.
Tooth loss, dementia and neuropathology in the Nun Study
J Am Dent Assoc
(2007) - et al.
Cognitive status of edentate elders wearing complete denture: Does quality of denture matter?
J Dent
(2015) - et al.
Effect of bite-raised condition on the hippocampal cholinergic system of aged SAMP8 mice
Neurosci Lett
(2012) - et al.
Vitamin D inhibits the expression of interleukin-8 in human periodontal ligament cells stimulated with Porphyromonas gingivalis
Arch Oral Biol
(2013)
Testing the Newcastle Ottawa Scale showed low reliability between individual reviewers
J Clin Epidemiol
Estimating the global mortality from Alzheimer’s disease and other dementias: A new method and results from the Global Burden of Disease study 2019: Epidemiology/prevalence, incidence, and outcomes of MCI and dementia
Alzheimers Dement
Mild cognitive impairment as a clinical entity and treatment target
Arch Neurol
Mild cognitive impairment: Conceptual, assessment, ethical, and social issues
Clin Interv Aging
Burden of oral disease among older adults and implications for public health priorities
Am J Public Health
Oral hygiene and oral health in older people with dementia: A comprehensive review with focus on oral soft tissues
Clin Oral Investig
Tooth loss increases the risk of diminished cognitive function: A systematic review and meta-analysis
JDR Clin Transl Res
Evidence summary: The relationship between oral health and dementia
Br Dent J
Tooth loss as a risk factor for dementia: Systematic review and meta-analysis of 21 observational studies
BMC Psychiatry
Association between residual teeth number in later life and incidence of dementia: A systematic review and meta-analysis
BMC Geriatr
Association between tooth loss and dementia among older people: A meta-analysis: Association between tooth loss and dementia among older people
Int J Geriatr Psychiatry
Periodontal disease, tooth loss and dementia: Is there a link? A systematic review
Gerodontology
Association between oral health and cognitive status: A systematic review
J Am Geriatr Soc
Influence of lack of posterior occlusal support on cognitive decline among 80-year-old Japanese people in a 3-year prospective study: Influence of occlusion on cognition
Geriatr Gerontol Int
Association between tooth loss and cognitive impairment in community-dwelling older Japanese adults: A 4-year prospective cohort study from the Ohasama study
BMC Oral Health
Preferred reporting items for systematic reviews and meta-analyses: The PRISMA Statement
PLoS Med
Critical evaluation of the Newcastle-Ottawa Scale for the assessment of the quality of non-randomized studies in meta-analyses
Eur J Epidemiol
GRADE: An emerging consensus on rating quality of evidence and strength of recommendations
BMJ
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XQ and ZZ contributed equally to this study and shared first authorship.
This study is partially supported by the National Institutes of Health (1R56AG067619 and U01DE027512).
The authors declare no conflicts of interest.