Prevalence and demographics of marijuana users in a Lung Cancer Screening cohort

Abstract

<b>Introduction:</b> Marijuana is the most widely used illicit drug in the world but its use is not included in models used to determine eligibility for Lung Cancer Screening (LCS) and if smoked with tobacco, may lead to an underestimation of smoking history. Here, we assess the prevalence and demographics of regular marijuana users in a LCS cohort. <b>Methods:</b> The SUMMIT Study aims to assess the implementation of low-dose CT (LDCT) screening for lung cancer in a high-risk population and validate a multi-cancer early detection blood test. Individuals aged 55-77 attended a Lung Health Check (LHC) to assess eligibility for study participation. Questions on smoking history and the use of substances other than cigarettes were included. <b>Results:</b> 16.4% (n=2135) of participants reported a history of marijuana use. 6.3% (n=824) had done so regularly (at least once a week) and 2.7% (n=357) were current, regular marijuana users at the time of the LHC. 74.4% (n=613) of current and former regular marijuana users were male and the mean age was 63.15 years. 81.6% (n=672) were of White ethnicity. 57.2% (n=471) were current cigarette smokers compared to 48.9% of the overall study cohort. Regular marijuana users did not differ significantly from the study cohort in terms of cigarette pack year history (44.9 and 45.3 respectively). 24.2% (n=199) of current and former regular marijuana users had higher education degrees compared to 17.2% (n=2236) of the overall study cohort. <b>Conclusion:</b> 6.3% of participants reported a history of regular marijuana use. They were more likely to be males, current cigarette smokers and have higher education degrees.&nbsp;Further research will determine the independent impact of marijuana use on lung cancer risk.