Social Development Measures Associated with Problem Behaviours and Weight Status in Australian Adolescents.

During the adolescent years, substance use, anti-social behaviours and overweight/obesity are amongst the major public health concerns. We investigate if risk and protective factors associated with adolescent problem behaviours and substance use are also associated with weight status in young Australian adolescents. Data comes from the 2006 Healthy Neighbourhoods study, a cross-sectional survey of students attending primary (grade 6, mean age 11) and secondary (grade 8, mean age 12) schools in 30 communities across Australia. Adolescents were classified as not overweight, overweight or obese according to international definitions. Logistic and linear regression analyses, adjusted for age, gender and socio-economic disadvantage quartile, were used to quantify associations between weight status (or BMI z-score) and the cumulative number of problem behaviour risk and protective factors. Prevalence of overweight and obesity was 22.6 % (95 % confidence interval (CI), 21.2-24.0 %) and 7.2 % (CI, 6.3-8.3 %). Average number of risk and protective factors present was 4.0 (CI, 3.7-4.2) and 6.2 (CI, 6.1-6.3). Independently, total number of risk factors present was positively associated with likelihood of overweight and obesity, while number of protective factors present was inversely associated with the likelihood of being above a healthy weight. When both risk and protective factors were included in a regression model, only risk factors were associated with the likelihood of being overweight or obese. Average BMI z-score increased by 0.03 units with each additional risk factor present. Prevention programmes targeting developmental risk and protective factors in adolescents that reduce substance use and problem behaviours may also benefit physical health.