Water pipe smoking and its association with cigarette and cannabis use in young adults in Switzerland

Background: Water pipe is a traditional method of tobacco use, which is epidemically spreading throughout Europe. There are scarce data about the use of water pipe and its relation to other addictive behaviors among young adults in Western countries. Objectives: It was our aim to identify the sociodemographic characteristics of water pipe users in Switzerland and to describe concurrent cigarette and cannabis smoking habits. Methods: Young adults aged 16-30 years were evaluated based on a 16-item standardized questionnaire on tobacco consumption and exhaled carbon monoxide. Current water pipe smoking was defined as water pipe use at least once within the last 4 weeks; regular water pipe smoking was defined as water pipe use at least once a week during the last 52 weeks. Results: Out of 353 volunteers, a total of 204 subjects (mean age 21 ± 3.5 years, 113 males) met the inclusion criteria for the study. A total of 78% (n = 160), 30.0% (n = 55) and 3.9% (n = 8) reported ever, current and regular water pipe smoking, respectively. Males smoked more often than females: 2.8 sessions/year (interquartile range 1.1-8) versus 2 sessions/year (interquartile range 0-4; p = 0.022). The major risk factor for ever smoking water pipe was cigarette smoking (odds ratio 6.22, 95% confidence interval 2.33-16.62), followed by cannabis consumption (odds ratio 1.44, 95% confidence interval 1.29-1.62). Ever water pipe smoking was more common among current cannabis users (100 vs. 0%; p > 0.0001) and related to higher exhaled carbon monoxide values (6.0 ± 9.0 vs. 2.1 ± 4.6 ppm; p > 0.001). Conclusion: Water pipe smoking is common among young adults and strongly associated with cigarette smoking and cannabis consumption.