RT Journal Article SR Electronic T1 Cigarette smoking and oral microbiota in low-income and African-American populations JF Journal of Epidemiology and Community Health JO J Epidemiol Community Health FD BMJ Publishing Group Ltd SP 1108 OP 1115 DO 10.1136/jech-2019-212474 VO 73 IS 12 A1 Yaohua Yang A1 Wei Zheng A1 Qiu-Yin Cai A1 Martha J Shrubsole A1 Zhiheng Pei A1 Robert Brucker A1 Mark D Steinwandel A1 Seth R Bordenstein A1 Zhigang Li A1 William J Blot A1 Xiao-Ou Shu A1 Jirong Long YR 2019 UL http://jech.bmj.com/content/73/12/1108.abstract AB Background Cigarette smoking is a common risk factor for diseases and cancers. Oral microbiota is also associated with diseases and cancers. However, little is known about the impact of cigarette smoking on the oral microbiota, especially among ethnic minority populations.Methods We investigated cigarette smoking in relationship with the oral microbiota in a large population of predominately low-income and African-American participants. Mouth rinse samples were collected from 1616 participants within the Southern Community Cohort Study, including 592 current-smokers, 477 former-smokers and 547 never-smokers. Oral microbiota was profiled by 16S ribosomal RNA gene deep sequencing.Results Current-smokers showed a different overall microbial composition from former-smokers (p=6.62×10−7) and never-smokers (p=6.00×10−8). The two probiotic genera, Bifidobacterium and Lactobacillus, were enriched among current-smokers when compared with never-smokers, with Bonferroni-corrected p values (PBonferroni ) of 1.28×10−4 and 5.89×10−7, respectively. The phylum Actinobacteria was also enriched in current-smokers when compared with never-smokers, with a median relative abundance of 12.35% versus 9.36%, respectively, and with a PBonferroni =9.11×10−11. In contrast, the phylum Proteobacteria was depleted in current smokers (PBonferroni =5.57×10−13), with the relative abundance being almost three times that of never-smokers (7.22%) when compared with that of current-smokers (2.47%). Multiple taxa within these two phyla showed differences in abundance/prevalence between current-smokers and never-smokers at PBonferroni <0.05. The differences in the overall microbial composition and abundance/prevalence of most taxa were observed among both African-Americans and European-Americans. Meanwhile, such differences were not observed between former-smokers and never-smokers.Conclusion Smoking has strong impacts on oral microbial community, which was recovered after smoking cessation.