INTRODUCTION: Waterpipe smoking is increasingly popular among North American youth. However, the extent to which waterpipe use is sustained over time is not known. The objective of this study was to describe the frequency and the predictors of sustained waterpipe use over 4 years among young adults.

METHODS: Data were available in a prospective cohort investigation of 1,293 seventh-grade students recruited in a convenience sample of 10 secondary schools in Montreal, Canada, in 1999. Data on past-year waterpipe use were collected from 777 participants when they were age 20 years on average (in 2007-2008) and again when they were age 24 years (in 2011-2012) in mailed self-report questionnaires. Twenty potential predictors of sustained waterpipe use were tested, each in a separate multivariable logistic regression model.

RESULTS: About 51% of 182 waterpipe users at age 20 reported waterpipe use 4 years later. Most sustained users (88%) smoked a waterpipe less than once a month. Parental smoking, being currently employed, less frequent cigarette smoking, and more frequent marijuana use were associated with sustained waterpipe use.

CONCLUSIONS: Half of the young adults who used waterpipe during young adulthood reported use 4 years later. Young adults who sustain waterpipe use appear to do so as an activity undertaken occasionally to socialize with others.