Correlates of solitary alcohol and cannabis use among American Indian adolescents

Background: Solitary substance use, or using substances while alone, is common among adolescents but understudied. This is the first study to examine solitary substance use among American Indian (AI) adolescents. The objective was to examine correlates of solitary alcohol use and solitary cannabis use that occur within the individual, family, school, peer, and cultural domains of the social ecology. Method: Data were from the 2009-2013 Drug Use Among Young American Indians Study, a cross-sectional cohort study. Two sets of hierarchical logistic regressions were conducted to examine solitary alcohol use (getting drunk) among lifetime alcohol users (n = 2082; Mage = 15.12 years; SD = 1.68; 54.2% female) and solitary cannabis use among lifetime cannabis users (n = 2085; Mage = 14.99 years; SD = 1.69; 50.5% female), including adjustment for level of substance involvement. Results: Prevalence of solitary alcohol use among lifetime drinkers was 24.9%. Among lifetime cannabis users, 53.6% reported solitary cannabis use. Regression analyses for solitary alcohol use showed statistically significant positive associations with coping motive, descriptive norms, violent behavior, depression, peer models for use, and (unexpectedly) peer sanctions against use and a negative association with family sanctions against use. Regression analyses for solitary cannabis use showed statistically significant positive associations with coping motive, violent behavior, and peer models for use and a negative association with family sanctions against use. Conclusions: Solitary alcohol and cannabis use are prevalent among AI adolescents and might, in particular, reflect attempts to cope with adversity. Findings could help guide the development of screening and prevention efforts.