No genetic causal associations between periodontitis and brain atrophy or cognitive impairment: evidence from a comprehensive bidirectional Mendelian randomization study

Bibliographic Details
Title: No genetic causal associations between periodontitis and brain atrophy or cognitive impairment: evidence from a comprehensive bidirectional Mendelian randomization study
Authors: Zhixing Deng, Jiaming Li, Yuhao Zhang, Yinian Zhang
Source: BMC Oral Health, Vol 24, Iss 1, Pp 1-16 (2024)
Publisher Information: BMC, 2024.
Publication Year: 2024
Collection: LCC:Dentistry
Subject Terms: Mendelian randomization analysis, Periodontitis, Brain atrophy, Cognitive impairment, Dentistry, RK1-715
More Details: Abstract Background Observational studies have explored the relationships of periodontitis with brain atrophy and cognitive impairment, but these findings are limited by reverse causation, confounders and have reported conflicting results. Our study aimed to investigate the causal associations of periodontitis with brain atrophy and cognitive impairment through a comprehensive bidirectional Mendelian randomization (MR) research. Methods We incorporated two distinct genome-wide association study (GWAS) summary datasets as an exploration cohort and a replication cohort for periodontitis. Four and eight metrics were selected for the insightful evaluation of brain atrophy and cognitive impairment, respectively. The former involved cortical thickness and surface area, left and right hippocampal volumes, with the latter covering assessments of cognitive performance, fluid intelligence scores, prospective memory, and reaction time for mild cognitive impairment to Alzheimer's disease (AD), Lewy body dementia, vascular dementia and frontotemporal dementia for severe situations. Furthermore, supplementary analyses were conducted to examine the associations between the longitudinal rates of change in brain atrophy and cognitive function metrics with periodontitis. The main analysis utilized the inverse variance weighting (IVW) method and evaluated the robustness of the results through a series of sensitivity analyses. For multiple tests, associations with p-values < 0.0021 were considered statistically significant, while p-values ≥ 0.0021 and < 0.05 were regarded as suggestive of significance. Results In the exploration cohort, forward and reverse MR results revealed no causal associations between periodontitis and brain atrophy or cognitive impairment, and only a potential causal association was found between AD and periodontitis (IVW: OR = 0.917, 95% CI from 0.845 to 0.995, P = 0.038). Results from the replication cohort similarly corroborated the absence of a causal relationship. In the supplementary analyses, the longitudinal rates of change in brain atrophy and cognitive function were also not found to have causal relationships with periodontitis. Conclusions The MR analyses indicated a lack of substantial evidence for a causal connection between periodontitis and both brain atrophy and cognitive impairment.
Document Type: article
File Description: electronic resource
Language: English
ISSN: 1472-6831
Relation: https://doaj.org/toc/1472-6831
DOI: 10.1186/s12903-024-04367-7
Access URL: https://doaj.org/article/fb48e0727ab74adf913a212bc4266d6a
Accession Number: edsdoj.fb48e0727ab74adf913a212bc4266d6a
Database: Directory of Open Access Journals
More Details
ISSN:14726831
DOI:10.1186/s12903-024-04367-7
Published in:BMC Oral Health
Language:English