Prevalence and Factors Associated with the Use of Psychoactive Substances by Adolescents in Public Schools in a Brazilian municipality

Objective: To estimate the prevalence and identify factors associated with the use of psychoactive substances by adolescents in public schools. Methods: : Cross-sectional study, which used randomized sample of adolescents from five public schools located in a city in the central-west region of the state of São Paulo, Brazil. Information on demographic and socioeconomic characteristics, and drug use were collected through self-reported questionnaires. The sample consisted of 1460 students, 716 (49.0%) boys, aged 10-19 years (13.19±2.04 years); 459 of the 744 girls were in post-menarche, with a mean age at menarche of 11.07±0.82 years. Results: : The prevalence of use of psychoactive substances in the last month was 51.0% for analgesics; alcohol 48.8%; tobacco 37.3%; tranquilizers 30.8%; marijuana 23.1%; anabolic steroids 22.6%; ecstasy 21.6%; amphetamines/stimulants 15.3%; phencyclidine 13.4%; cocaine/crack 12.9%; inhalants/solvents 12.6%; opiates 11.5%; hallucinogens 11.4%; and other unclassified drugs 16.2%. In the correlation analysis between different types of drugs, positive relationships of strong magnitude (r = .400 to .690) and highly significant (p< .01) were identified between the use of several psychoactive drugs. Elementary school students were more likely to consume tobacco (OR= 2.306; 95%CI 1.733, 3.068; p< 0.001), and male students were more likely to consume any type of substance. Conclusion: We identified a high use of psychoactive substances among the participants in this study, with a higher prevalence among male students.