There is a paucity of data on nicotine and cannabis use among young adults (YAs) with asthma. This study aimed to do the following among YAs with asthma: (1) describe YAs' active and passive exposure to nicotine and cannabis; (2) identify latent classes of active use of nicotine and cannabis; and (3) explore predictors of class membership (i.e., demographics, parental and friend use of nicotine and cannabis, and hours of environmental exposure to tobacco smoke, e-cigarette vapor, and marijuana smoke). YAs with asthma (N = 178) self-reported on nicotine and cannabis exposure and the included covariates. Latent class analysis was used to identify latent classes of lifetime nicotine and cannabis use. High rates of nicotine and cannabis use among YAs with asthma were found: 37% reporting a lifetime history of using both nicotine and cannabis. Regarding past year use, 25% had smoked cigarettes, 40% had used e-cigarettes, and 35% had used cannabis. Five classes of lifetime use were identified. The largest class was a non-user class (53%); the other four classes indicate concerning patterns of nicotine and cannabis use. The most consistent predictor of being in a class characterized by more nicotine and cannabis exposure (versus being in the non-user class) was past week exposure to cannabis smoke. This is the first study to identify classes of lifetime nicotine and cannabis use, and examine predictors of class membership, among YAs with asthma. There is a critical need to address environmental and active tobacco and marijuana exposure among YAs with asthma.
Keywords: asthma; cannabis; environmental smoke exposure; nicotine.