A meta-analysis of marijuana and alcohol use by socio-economic status in adolescents aged 10-15 years.

OBJECTIVES A majority of population-based studies suggest prevalence of drug and alcohol risk behaviour increases during late adolescence to early adulthood. The purpose of this systematic literature review is to clarify if socio-economic status (SES) is a determinant of marijuana and alcohol risk behaviour in adolescents between the ages of 10-15 years. METHODS We performed a meta-analysis to identify published or unpublished papers between January 1, 1980 and February 9, 2007 that reviewed marijuana and alcohol risk behaviour by SES in adolescents aged 10-15 years. SYNTHESIS We found nine studies that fulfilled our inclusion criteria and passed the methodological quality review. The prevalence of marijuana and alcohol risk behaviour was 22% higher (RR = 1.22; 95% CI 1.14-1.31) in adolescents with low SES in comparison to adolescents with higher SES. Stratification by country of origin revealed that American and New Zealand studies had statistically significant variability in the reported effects as compared to European and UK studies. DISCUSSION The evidence suggests that low SES has an inverse association with the prevalence of marijuana and alcohol risk behaviour in adolescents between the ages of 10-15 years. Higher rates of marijuana and alcohol risk behaviour among lower SES adolescents may impact emotional development, limit future educational and occupational achievement, and increase the likelihood for adult marijuana and alcohol addiction. CONCLUSION Lower SES adolescents have higher rates of marijuana and alcohol risk behaviour than higher SES adolescents.