Mexicans' use of illicit drugs in an era of drug reform: national comparative analysis by migrant status.

Background: Although rates of illicit drug use are considerably lower in Mexico than in the United States, rates in Mexico have risen significantly. This increase has particular implications for Mexican women and US migrants, who are considered at increased risk of drug use. Due to drug reforms enacted in Mexico in 2008, it is critical to evaluate patterns of drug use among migrants who reside in both regions.

Methods: We analysed a sample of Mexicans (N=16,249) surveyed during a national household survey in 2011, the Encuesta Nacional de Adicciones (National Survey of Addictions). Comparative analyses based on Mexicans' migrant status - (1) never in the United States, (2) visited the United States, or (3) lived in the United States (transnationals) - featured analysis of variance and Chi-square global tests. Two multilevel regressions were conducted to determine the relationships among migrant status, women, and illicit drug use.

Results: Comparative findings showed significant differences in type and number of drugs used among Mexicans by migrant status. The regression models showed that compared with Mexicans who had never visited the United States, Mexican transnationals were more likely to report having used drugs (OR=2.453, 95% CI=1.933, 3.113) and using more illicit drugs (IRR=2.061, 95% CI=1.626, 2.613). Women were less likely than men to report having used drugs (OR=0.187, 95% CI=0.146, 0.239) and using more illicit drugs (IRR=0.153, 95% CI=0.116, 0.202).

Conclusions: Overall, the findings support further exploration of risk factors for illicit drug use among Mexican transnationals, who exhibit greater drug use behaviours than Mexicans never in the United States. Because drug reform mandates referrals to treatment for those with recurrent issues of drug use, it is critical for the Mexican government and civic society to develop the capacity to offer evidence-based substance abuse treatment for returning migrants with high-risk drug behaviours.