Shifting Substance Use Patterns Across Generations Revealed

The co-use of substances confers risks above single-product use and has significant public health implications. This study investigated trends in past 30-day co-use of nicotine/tobacco products with alcohol and cannabis in the US using Population Assessment of Tobacco and Health Study data from Waves 4-6 (December 2016-November 2021). All wave 4-6 PATH participants age 15+ were included in analyses. Changes across wave in past 30-day co-use of cigarettes, e-cigarettes, and other tobacco products (OTP; cigars, filtered cigars, smokeless, hookah, snus, and cigarillo) with alcohol and cannabis, moderated by age (15-17,18-24, 25-34,35-64, 65+), and controlling for demographics were investigated. Changes in co-use of tobacco products with cannabis and alcohol varied across age and product. Cigarette and alcohol co-use was most prevalent across all adult ages, with rates declining over time among young adults (18-24, 25-34) but stable in older adults (65+). Rates of e-cigarette and alcohol co-use increased among young adults, possibly supplanting alcohol and cigarette co-use. E-cigarette and alcohol co-use was the most popular pattern of co-use in youth, with initially increasing and then declining prevalence. Co-use of e-cigarette and cannabis increased at Wave 5 among those 15-17, 18-24, and 25-34, although this increase lessened in all groups except those age 25-34 at Wave 6. Cigarette and cannabis co-use rates, and co-use rates of OTP with both cannabis and alcohol were generally stable or decreasing. Findings highlight the complex interplay between substance use patterns and developmental stages and the dynamic nature of co-use in ever-evolving tobacco and cannabis marketplaces.