Patterns of health-related behaviours among adolescents: a cross-sectional study based on the National Survey of School Health Brazil 2012.

OBJECTIVES: The aim of this study was to analyse the clustering of multiple health-related behaviours among adolescents and describe which socio-demographic characteristics are associated with these patterns. DESIGN: Cross-sectional study. SETTING: Brazilian schools assessed by the National Survey of School Health (PeNSE, 2012). PARTICIPANTS: 104 109 Brazilian ninth-grade students from public and private schools (response rate=82.7%). METHODS: Exploratory and confirmatory factor analyses were performed to identify behaviour clustering and linear regression models were used to identify socio-demographic characteristics associated with each one of these behaviour patterns. RESULTS: We identified a good fit model with three behaviour patterns. The first was labelled 'problem-behaviour' and included aggressive behaviour, alcohol consumption, smoking, drug use and unsafe sex; the second was labelled 'health-compromising diet and sedentary behaviours' and included unhealthy food indicators and sedentary behaviour; and the third was labelled 'health-promoting diet and physical activity' and included healthy food indicators and physical activity. No differences in behaviour patterns were found between genders. The problem-behaviour pattern was associated with male gender, older age, more developed region (socially and economically) and public schools (compared with private). The 'health-compromising diet and sedentary behaviours' pattern was associated with female gender, older age, mothers with higher education level and more developed region. The 'health-promoting diet and physical activity' pattern was associated with male gender and mothers with higher education level. CONCLUSIONS: Three health-related behaviour patterns were found among Brazilian adolescents. Interventions to decrease those negative patterns should take into account how these behaviours cluster together and the individuals most at risk.