RT Journal Article SR Electronic T1 Lifetime cannabis exposure and small airway function in a population-based cohort study JF ERJ Open Research JO erjor FD European Respiratory Society SP 00688-2021 DO 10.1183/23120541.00688-2021 A1 Tan, Hua Shin A1 McAnally, Helena M. A1 Dummer, Jack A1 Hancox, Robert J. YR 2022 UL https://publications.ersnet.org//content/early/2022/03/10/23120541.00688-2021.abstract AB Background and objective The long-term effects of cannabis on small airway function remain unclear. We investigated associations between cannabis use and small airway function in a general population sample.Methods Cannabis use was ascertained at multiple ages from age 18 to 45 years and quantified as joint-years among 895 participants in the Dunedin Multidisciplinary Health and Development Study. Small airway function at ages 38 and 45 years was measured using impulse oscillometry before and after inhalation of salbutamol. Analyses used multiple linear regression adjusting for tobacco use, body mass index, and height. Longitudinal analyses of cannabis use between 38 and 45 years also adjusted for IOS at age 38.Results Lifetime cannabis joint-years with IOS differed between men and women: in women, cannabis use was associated with pre-bronchodilator R5, R20, X5, AX, and Fres and marginally associated with R5-R20. Cannabis use was not statistically significantly associated with any of the pre-bronchodilator IOS measures in men. Cannabis use between ages 38 and 45 was associated with a similar pattern of changes in IOS measures. After salbutamol, cannabis use was only statistically significantly associated with R5 and R20 among women and none of the IOS measures among men.Conclusions Cannabis use is associated with small airway dysfunction at age 45 years, indicating an increase in peripheral airway resistance and reactance. These associations were greater and only statistically significant among women. Associations were weaker and mostly non-significant after bronchodilator use suggesting that cannabis-induced changes in small airways may be at least partially reversible.FootnotesThis manuscript has recently been accepted for publication in the ERJ Open Research. It is published here in its accepted form prior to copyediting and typesetting by our production team. After these production processes are complete and the authors have approved the resulting proofs, the article will move to the latest issue of the ERJOR online. Please open or download the PDF to view this article.Conflict of interest: Dr. McAnally reports support for the present manuscript received from Health Research Council (NZ), MBIE (NZ), MRC (UK), and NIA (US).Conflict of interest: Dr. Hancox reports support for the present manuscript received from Health Research Council (NZ), MBIE (NZ), MRC (UK), and NIA (US). Support for attending meetings and/or travel received from Asian Pacific Society of Respirology Congress 2019, for which the author has an invited speaker, disclosure made outside the submitted work. Leadership or fiduciary role in other board, society, committee or advocacy group for Scientific Committee for Asthma and Respiratory Foundation of NZ, unpaid; disclosure made outside the submitted work.Conflict of interest: Dr. Shin Tan reports support for the present manuscript received from Health Research Council (NZ), MBIE (NZ), MRC (UK), and NIA (US).Conflict of interest: Dr. Dummer has nothing to disclose.