Compositional shifts within the denture-associated bacteriome in pneumonia - an analytical cross-sectional study

Twigg, Joshua A.; Smith, Ann; Haury, Clotilde; Wilson, Melanie J.; Lees, Jonathan; Waters, Mark; Williams, David W.

Abstract

Introduction. Bacterial pneumonia is a common cause of morbidity and mortality in elderly individuals. While the incidence of edentulism is falling, approximately 19 % of the UK population wear a full or partial removable denture. Despite advances in denture biomaterials, the majority of dentures are fabricated using polymethyl-methacrylate. Growing evidence suggests that colonization of the oral cavity by putative respiratory pathogens predisposes individuals to respiratory infection, by translocation of these microorganisms along the respiratory tract.Hypothesis/Gap Statement. We hypothesized that denture surfaces provide a susceptible colonization site for putative respiratory pathogens, and thus could increase pneumonia risk in susceptible individuals.Aim. This study aimed to characterize the bacterial community composition of denture-wearers in respiratory health compared with individuals with a confirmed diagnosis of pneumonia.Methodology. This was an analytical cross-sectional study, comparing frail elderly individuals without respiratory infection (n=35) to hospitalized patients with pneumonia (n=26). The primary outcome was the relative abundance of putative respiratory pathogens identified by 16S rRNA metataxonomic sequencing, with quantitative PCR used to identified Streptococcus pneumoniae.Results. There was a statistically significant increase in the overall relative abundance of putative respiratory pathogens (P<0.0001), with a greater than 20-fold increase in the bioburden of these microorganisms. In keeping with these findings, there were significant shifts in bacterial community diversity (Chao index, P=0.0003) and richness (Inverse Simpson index P<0.0001) in the denture-associated microbiota of pneumonia patients compared with control subjects.Conclusion. Within the limitations of this study, our evidence supports the role of denture acrylic biomaterials as a potential colonization site for putative respiratory pathogens, which may lead to an increased risk of pneumonia in susceptible individuals. These findings support prior observational studies which have found denture-wearers to be at increased risk of respiratory infection. Further research is needed to confirm the sequence of colonization and translocation to examine potential causal relationships.

• Journal Article Type: Article
• Acceptance Date: May 1, 2023
• Online Publication Date: Jun 21, 2023
• Publication Date: Jun 21, 2023
• Deposit Date: Jun 23, 2023
• Publicly Available Date: Jun 28, 2023
• Journal: Journal of Medical Microbiology
• Print ISSN: 0022-2615
• Electronic ISSN: 1473-5644
• Publisher: Microbiology Society
• Peer Reviewed: Peer Reviewed
• Volume: 72
• Issue: 6
• DOI: https://doi.org/10.1099/jmm.0.001702
• Keywords: General Medicine, Microbiology, 16S rRNA, metataxonomic sequencing, bacterial pneumonia, denture, bacteriome
• Public URL: https://uwe-repository.worktribe.com/output/10883646
• Publisher URL: https://www.microbiologyresearch.org/content/journal/jmm/10.1099/jmm.0.001702