Using e-cigarettes may alter oral microbiome, increase gum disease risk: Study

Vaping may alter the community of different species of bacteria living in the mouth, making users more prone to inflammation and infection, according to a study that may lead to stronger interventions against e-cigarette use.

The study, published in the journal iScience, noted that the mouth harbours many microbial species (microbiome) that colonise our respiratory and digestive tracts, and said smoking raises the risk of gum disease by fostering an environment conducive for infection-causing bacteria to flourish.

"Given the popularity of vaping, it is critical that we learn more about the effects of e-cigarette aerosols on the oral microbiome and host inflammatory responses in order to better understand the impact of vaping on human health," said Xin Li, study co-author from New York University (NYU) in the US.

"The oral microbiome is of interest to us because research shows that changes in its microbial community as a result of environmental and host factors contribute to a range of health issues, including cavities, gum disease, halitosis, and medical conditions such as diabetes, cardiovascular disease, and cancers," said Deepak Saxena, another co-author from NYU.

In the study, Saxena and his colleagues examined e-cigarette vapour, and its influence on the oral microbiome and immune health.

They also evaluated how vaping affects the infection efficiency of oral pathogens in cell lines.

The scientists studied the oral microbiome of 119 human participants from three groups -- e-cigarette users, regular cigarette smokers, and those who had never smoked.

They found that gum disease or infection was significantly higher among cigarette smokers (72.5 percent), followed by e-cigarette users (42.5 percent), and non-smokers (28.2 percent).

The researchers observed different microorganisms in the saliva of e-cigarette users, cigarette smokers, and non-smokers.

They said e-cigarette users had an abundance of Porphyromonas bacteria, while an increase in Veillonella bacteria was found in both e-cigarette and cigarette users.

"The predominance of these periodontal pathogens in the mouths of e-cigarette users and traditional smokers is a reflection of compromised periodontal health," Li said.

The scientists also found that the altered microbiome in e-cigarette users influenced the local host immune environment compared to non-smokers and cigarette smokers.

According to the study, e-cigarette aerosols made cells prone to bacterial infection, pointing to a greater risk for infection in e-cigarette users.

"Our study suggests that vaping electronic cigarettes causes shifts in the oral environment and highly influences the colonisation of complex microbial biofilms, which raises the risk for oral inflammation and infection," Saxena said.