Young adults exposed to second-hand nicotine vape were at increased risk of bronchitic symptoms and shortness of breath, US researchers report.

Researchers surveyed 2,097 participants annually between 2014 (mean age 17.3 years) and 2019.

The proportion exposed to second-hand nicotine vape at home rose from 11.7 to 15.6 per cent, while second-hand smoking declined from 26.6 to 20.6 per cent.

The proportion that self-reported wheeze and bronchitic symptoms increased during this time.

Allowing for confounders, exposure to second-hand vape was associated with a 40 per cent increase in the risk of bronchitic symptoms and a 53 per cent increase in shortness of breath in the previous year.

The 21 per cent increase in the risk of wheeze was not statistically significant. Since participants self-reported respiratory health for the previous year, some symptoms may have been under-reported.

Nevertheless, the authors comment that, “the estimated effects of second-hand nicotine vape exposure on bronchitic symptoms in this study were similar in magnitude to those of second-hand smoking”.

(Thorax doi:10.1136/thoraxjnl-2021-217041)