Objectives

Smoking is associated with shifts in the composition of the oral microbiome that can contribute to the development and progression of periodontitis in adults [1]. While most smokers start smoking before the age of 18 [2], data on the effects of smoking on the oral microbiome in adolescents is very limited. The current study investigates the effects of smoking on the composition of the oral microbiome in a local cohort of secondary-school pupils.

Materials and Methods

The adolescent cohort of this study comprised 196 secondary-school pupils aged 14 to 21, who were sampled between June and December 2020. We collected a swab of the buccal mucosa as well as information on smoking behavior from every participant. 98 adolescent smokers fulfilled the inclusion criteria. Their oral microbiome composition was compared to that of 98 non-smokers matched for age, gender, BMI and medication intake. The oral microbiome composition was analysed using high-throughput sequencing of the full-length 16S rRNA gene. Analyses of bacterial diversity, abundance comparisons of individual bacterial taxa in smokers and non-smokers, and other statistical analyses were performed.

Results

Smoking pupils were distributed over five categories of smoking frequencies from "less than once/month" to "every day". Thirteen of 98 smokers smoked daily. None of the pupils met the definition for heavy smokers (more than 20 cigarettes per day). Overall microbiota composition as measured by weighted UniFrac distances differed significantly between smokers and non-smokers. Smoking exerted a discernible influence on the abundance of several key microbial families, indicating an early onset in smoking-related changes in the oral microbiome.

Conclusion

This study shows the early onset of smoking-related alterations in the oral microbiome.

References

[1] Shchipkova, A. Y., Nagaraja, H. N., & Kumar, P. S. (2010). Subgingival microbial profiles of smokers with periodontitis. Journal of dental research, 89(11), 1247–1253. https://doi.org/10.1177/0022034510377203

[2] DEBRA: https://www.debra-study.info/wp-content/uploads/2022/12/Factsheet-09-v3.pdf