A newly published critical umbrella review in Tobacco Use Insights found that there were no statistically significant changes in respiratory function for e-cigarette (EC) users. Conducted by researchers from the Center of Excellence for the Acceleration of Harm Reduction (CoEHAR), the study highlights the absence of significant short- or medium-term respiratory changes associated with e-cigarette use, regardless of usage patterns.
Led by Giusy Rita Maria La Rosa, Riccardo Polosa, and Renée O’Leary, the review analyzed 12 systematic reviews on e-cigarette effects, categorizing users into three groups: dual users (who smoke and vape), exclusive users (former smokers who switched to vaping), and naïve users (those who have never smoked but use e-cigarettes).
“Studies on the latest products on the market have shown reductions in chemical emissions,” said O’Leary. “Across all user categories, there were no statistically significant changes in respiratory function. The five systematic reviews in our analysis concluded that there is no definitive evidence of harm or benefit regardless of the pattern of EC use”
“Current data do not show significant respiratory variations associated with e-cigarette use in the short or medium term,” La Rosa added. “However, due to the lack of adequate longitudinal studies, no definitive conclusions can be drawn.”
The researchers said their results, which vary from many others around the industry, can be explained by considering several important factors: acute studies provide data on short-term exposure to e-cigarettes and cannot be used to assess long-term effects; studies do not always account for participants’ smoking history; and individuals with low-frequency e-cigarette use are often grouped together with those who use e-cigarettes more frequently.
Regarding the quality of the included studies, only five out of 12 reviews were rated as having high or moderate confidence in their findings. Reporting issues were common.
“The study highlights the importance of distinguishing between different vaping behaviors in future research, as well as addressing methodological weaknesses and biases observed in many previous studies on the topic,” Polosa said. “But it allows us to state once again that vaping cannot be associated to significant changes in respiratory function.”