Oral Health and Pneumonia in Adults With Intellectual and Developmental Disabilities: A Scoping Review

Pneumonia is a leading cause of death for people with intellectual and developmental disabilities (IDD), who also have increased risk of oral disease. Given the known relationship between oral disease and pneumonia in similar populations, this review aims to explore what is known about the association between oral health and pneumonia among people with IDD.

This systematic scoping review was carried out in accordance with the Joanna Briggs Institute methods and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews checklist (PRISMA-ScR). A systematic search of Medline (Ovid), Embase, Cochrane Trials, Cochrane Review, CINAHL and PubMed was conducted, guided by a registered protocol. The PCC framework informed the search and inclusion criteria. Titles and abstracts were independently screened by two reviewers, with full texts assessed for relevance to oral health and pneumonia in adults with IDD.

Following a protocol and defined criteria, (2544) articles were abstract screened; a further (31) reached full-text review, with (7) included in this review. Study designs included cross-sectional studies (2), retrospective cohorts (2), prospective cohorts (2) and one RCT pilot (1). Six studies reported oral carriage of respiratory pathogens such as Streptococcus pneumoniae, Pseudomonas aeruginosa and Klebsiella pneumoniae. Two studies reported predictive relationships between oral pathogens and pneumonia, with increased odds of respiratory illness associated with positive PCR results for specific pathogens (OR 9.0, 95% confidence interval [CI] 2.3-38.8). Two studies identified poor oral health as a predictor of pneumonia, using validated tools such as the ROAG (OR 1.6, 95% CI 1.1-2.5). Mediating factors included enteral feeding, level of IDD, and history of oral disease.

Research consistently finds carriage of potential respiratory pathogens in the oral microbiome of people with IDD. Despite this, there is a significant lack of research into the relationship between the oral microbiome, poor oral health, and pneumonia in this population, though the latter two are both prevalent and consequential. There is an urgent need for further research exploring the role that oral health and the oral microbiome play in pneumonia among people with IDD.