Association between binge drinking, type of friends and gender: A cross-sectional study among Brazilian adolescents

BACKGROUND Hazardous drinking among adolescents is a major public health concern. The purpose of this study was to examine the prevalence of binge drinking/alcohol consumption and its association with different types of friendship networks, gender and socioeconomic status among students in Belo Horizonte, Minas Gerais, Brazil. METHODS We conducted a cross-sectional study on a representative random sample of 891 adolescents (41% male, aged 15-19 years) from public and private schools in 2009-2010. Information on friendship networks and binge drinking was collected using two validated self-administered questionnaires: the Integrated Questionnaire for the Measurement of Social Capital and the first 3 items in the Alcohol Use Disorders Identification Test (AUDIT C). We used the area-based Social Vulnerability Index (SVI), mother and father's educational background, and the type of school to assess socioeconomic status. The chi-squared test was used to examine the associations between sample characteristics or the type of friends and binge drinking (p-values <0.05 were considered statistically significant). Ordinal logistic regression was used to estimate the association between binge drinking and the independent variables. RESULTS A total of 321 (36%) adolescents reported binge drinking (5 or more drinks in one occasion), and among them, 233 (26.2%) adolescents reported binge drinking less than monthly to monthly, and 88 (9.9%) weekly to daily. Binge drinking was associated with being male (OR = 1.52, 95% CI 1.01-2.28) and with living in a low vulnerability area (having the best housing conditions, schooling, income, jobs, legal assistance and health) (OR = 1.66, 95% CI 1.05-2.62). Students who reported that their closest friends were from school (as opposed to friends from church) had an increased risk of binge drinking (OR = 3.55, 95% CI 1.91-5.87). In analyses stratified by gender, the association was significant only among the female students. CONCLUSIONS The prevalence of binge drinking was high in this sample of Brazilian adolescents, and gender, low social vulnerability and friendship network were associated with binge drinking.