Trends in alcohol and tobacco use among Brazilian students: 1989 to 2010

OBJECTIVE To analyze temporal trends of the prevalence of alcohol and tobacco use among Brazilian students. METHODS We analyzed data published between 1989 and 2010 from five epidemiological surveys on students from the 6th to the 12th grade of public schools from the ten largest state capitals of Brazil. The total sample consisted of 104,104 students and data were collected in classrooms. The same collection tool – a World Health Organization self-reporting questionnaire – and sampling and weighting procedures were used in the five surveys. The Chi-square test for trend was used to compare the prevalence from different years. RESULTS The prevalence of alcohol and tobacco use varied among the years and cities studied. Alcohol consumption decreased in the 10 state capitals (p < 0.001) throughout 21 years. Tobacco use also decreased significantly in eight cities (p < 0.001). The highest prevalence of alcohol use was found in the Southeast region in 1993 (72.8%, in Belo Horizonte) and the lowest one in Belem (30.6%) in 2010. The highest past-year prevalence of tobacco use was found in the South region in 1997 (28.0%, in Curitiba) and the lowest one in the Southeast in 2010 (7.8%, in Sao Paulo). CONCLUSIONS The decreasing trend in the prevalence of tobacco and alcohol use among students detected all over the Country can be related to the successful and comprehensive Brazilian antitobacco and antialcohol policies. Despite these results, the past-year prevalence of alcohol consumption in the past year remained high in all Brazilian regions.

研究目的：分析巴西学生烟酒使用流行率的时间变化趋势。
研究方法：本研究分析了1989年至2010年间发布的五项流行病学调查数据，调查对象为巴西十大州府公立学校6至12年级的学生，总样本量为104104名学生，数据通过课堂方式采集。五项调查均采用统一的采集工具——世界卫生组织（World Health Organization，WHO）自陈问卷，以及统一的抽样与加权流程。本研究采用趋势卡方检验（Chi-square test for trend）比较不同年份的流行率差异。
研究结果：不同年份与研究城市的烟酒使用流行率存在差异。21年间，十大州府的酒精消费率呈下降趋势（p<0.001）；八个城市的烟草使用流行率也显著下降（p<0.001）。酒精使用流行率最高值出现在1993年的东南部地区贝洛奥里藏特（72.8%），最低值则为2010年的贝伦（30.6%）。过去一年烟草使用流行率最高值出现在1997年的南部地区库里蒂巴（28.0%），最低值为2010年东南部地区圣保罗（7.8%）。
研究结论：巴西全国范围内检测到的学生烟酒使用流行率下降趋势，或与巴西成功推行的全面控烟、控酒政策相关。尽管取得上述成果，巴西各地区学生过去一年的酒精消费率仍处于较高水平。