A leading respiratory expert has cautioned against generalising the findings of a study that found vaping was not associated with changes in the lung health of nine people who had never smoked.
The observational study (read full paper here) presented by Professor Riccardo Polosa at the Asian Pacific Respiratory Conference in Sydney at the weekend included vapers with an average age of 27-29 who had never smoked and were exposed to an average of 4mls of e-liquid each day for over three and a half years.
No differences were observed in measures of lung function or exhaled biomarkers of inflammation (breath nitric oxide and carbon monoxide), blood pressure or heart rate at baseline or between a reference group of 12 never smokers.
The research team from Italy also found no significant structural abnormalities on the high resolution CT scans between the groups.
“While the sample size was small the results of the study may provide some preliminary evidence that long-term use of electronic cigarettes is unlikely to raise significant health concerns in relatively young users,” they concluded, while cautioning that is was possible harm could occur at later stages.
They also acknowledged that the study subjects had a generally short duration of regular electronic cigarette (EC) use prior to entering the study (on average 8 months) and vaporised, on average, a modest amount of e-liquid (about 4 ml), which may not be representative of the general population of EC users who never smoked.
“Consequently, firm conclusions cannot be drawn from the results and additional studies in a larger and more diverse group of EC users are needed,” they said.
Professor Matthew Peters, former President of TSANZ, who presented in the same APSR session, agreed with Professor Polosa about the limitations of the study.
“This study shows that there is not a rapid, consistent and dramatic loss of lung function in electronic cigarette users who use low volumes of e-liquid.
“As we would never expect to detect harms in terms of lung function or CT appearance over this short period in a similarly small group of smokers, it is most unwise to conclude that this study tells us anything meaningful about long-term safety,” he said.
“It was pleasing to hear Professor Polosa, who clearly has an interest in the area, emphasise the preliminary nature of this study and express his significant concerns about lung health in those who consume large volumes of e-liquid.”