Investigating how perceived risk and availability of marijuana relate to marijuana use among adolescents in Argentina, Chile, and Uruguay over time

• Published in: Drug and alcohol dependence Vol. 201; pp. 115 - 126
• Main Authors: Schleimer, Julia P., Rivera-Aguirre, Ariadne E., Castillo-Carniglia, Alvaro, Laqueur, Hannah S., Rudolph, Kara E., Suárez, Héctor, Ramírez, Jessica, Cadenas, Nora, Somoza, Matías, Brasesco, Maria V., Martins, Silvia S., Cerdá, Magdalena
• Format: Journal Article
• Language: English
• Published: Ireland Elsevier B.V 01-08-2019; Elsevier Science Ltd
• Subjects: Adolescent; Adolescent Behavior; Adolescents; Argentina - epidemiology; Availability; Bivariate analysis; Cannabis; Chile - epidemiology; Cross-Sectional Studies; Female; Health Surveys; Humans; Male; Marijuana; Marijuana Use - epidemiology; Marijuana Use - psychology; Perceived availability; Perceived risk; Risk analysis; Risk Factors; Risk perception; Teenagers; Time-varying effect modeling; Uruguay - epidemiology; Young Adult; Chile; Uruguay; Argentina; Perceived risk; Marijuana; Perceived availability; Adolescent; Time-varying effect modeling
• ISSN: 0376-8716; 1879-0046
• DOI: 10.1016/j.drugalcdep.2019.03.029

•Adolescent marijuana use increased amid liberalized marijuana regulation.•Perceived risk became a weaker correlate of adolescent marijuana use.•Perceived availability remained strongly associated with use.•Marijuana availability may become an increasingly important driver of use.
Amid changing marijuana policies in the Southern Cone, we examined relationships between marijuana-related risk factors and marijuana use among adolescents in Argentina, Chile, and Uruguay from 2001 to 2016.
Using cross-sectional surveys from 8th, 10th, and 12th graders and weighted time-varying effect models, we estimated associations between perceived risk (no/low risk versus moderate/great risk) and perceived availability (easy/very easy versus difficult/very difficult/not able to obtain) of marijuana, and any past-month marijuana use.
In all countries, marijuana use increased over time and adolescents who perceived no/low risk and easy availability had higher odds of use. In Argentina, the bivariate risk/use association weakened from 2001 (OR = 15.24, 95%CI = 9.63, 24.12) to 2004 [OR = 3.86 (2.72, 5.48)] and strengthened until 2011 [OR = 8.22 (7.56, 10.30)]; the availability/use association strengthened from 2005 [OR = 5.32 (4.05, 6.98)] to 2009 [OR = 20.77 (15.57, 27.70)] and weakened until 2014 [OR = 11.00 (9.11, 13.27)]. In Chile, the risk/use association weakened from 2001 [OR = 7.22 (6.57, 7.95)] to 2015 [OR = 5.58 (4.82, 6.48)]; the availability/use association weakened from 2001 [OR = 5.92 (4.96, 7.06)] to 2015 [OR = 4.10 (3.15, 5.34)]. In Uruguay, the risk/use association weakened from 2003 [OR = 34.22 (22.76, 51.46)] to 2016 [OR = 6.23 (4.96, 7.83)]; the availability/use association weakened from 2005 [OR = 29.13 (13.39, 63.39) to 2007 [OR = 9.42 (3.85, 23.07)], and strengthened until 2016 [OR = 22.68 (12.03, 42.76)].
Overall, the association between risk and use weakened in all countries, suggesting risk perceptions became a weaker determinant of marijuana use. Perceived availability remained strongly associated with use and may become an increasingly important driver of use (particularly in Uruguay and Argentina).