Latent Classes of Substance Use Among American Indian and White Students Living on or Near Reservations, 2009-2013.

Objectives: American Indian adolescents who reside on or near reservations report higher levels of substance use than adolescents in other racial/ethnic groups. Little research has addressed patterns of use, which have important implications for prevention and treatment planning. The objective of our study was to describe substance use among a large, population-based sample of American Indian and white students who lived on or near reservations.

Methods: We obtained data from 4964 students in grades 7-12 attending 46 schools on or near reservations throughout the United States during 4 academic years (2009-2013). Measures assessed current substance use for alcohol, heavy drinking, marijuana, cigarettes, inhalants, and other drugs. We used latent class analysis to identify patterns of substance use by grade group (grades 7-8 and grades 9-12) and race (American Indian or white).

Results: For American Indians in both grade groups, we found 4 classes of substance use (in order of size): (1) nonusers; (2) marijuana and cigarette users; (3) alcohol, marijuana, and cigarette users; and (4) polysubstance users. For white students, we found 2 classes (nonusers and polysubstance users) among younger students and 4 classes (nonusers; alcohol, marijuana, and cigarette users; alcohol and cigarette users; and polysubstance users) among older students.

Conclusion: We found significant differences in substance use patterns, especially at younger ages, between reservation American Indian students and white students attending the same schools. Combinations of substances used by American Indian adolescents were most likely to include marijuana, as compared with alcohol for white adolescents. Identifying subpopulations of users allows the design of interventions that will more efficiently and effectively address prevention and treatment needs of groups of individuals than would a one-size-fits-all approach.