Age Differences in Daily and Nondaily Cannabis Use in the United States, 2002–2014

Objective:Adult cannabis use has increased in the United States since 2002, particularly after 2007, contrasting with stable/declining trends among youth. We investigated whether specific age groups disproportionately contributed to changes in daily and nondaily cannabis use trends.Method:Participants ages 12 and older (N = 722,653) from the 2002–2014 National Survey on Drug Use and Health reported past-year cannabis use frequency (i.e., daily = ≥300 days/year; nondaily = 1–299 days/year; none). Multinomial logistic regression was used to model change in past-year daily and nondaily cannabis use prevalence by age group (i.e., 12–17, 18–25, 26–34, 35–49, 50–64, ≥65), before and after 2007. Multinomial logistic regressions estimated change in relative odds of cannabis use frequency over time by age, adjusting for other sociodemographics.Results:Daily cannabis use prevalence decreased in ages 12–17 before 2007 and increased significantly across adult age categories only after 2007. Increases did not differ s...