Gender differences and the role of parental education, school types and migration on the body mass index of 2930 Austrian school children

Austria faces increasing numbers of childhood overweight and obesity. Despite increasing numbers of studies, associations between parental body mass index (BMI) and education and the school type on overweight/obesity in students have not been reported. The objective of this study was to evaluate the influence of these parameters on the genesis of overweight/obesity in a large cohort representative of youth in Upper Austrian.

A cross-sectional analysis of data from 2930 children and adolescents aged 10, 14 or 17 years from 11 different state school types was conducted. Students and their parents completed a questionnaire and heights and weights were measured.

Of the students 16.9% fulfilled the criteria for overweight and 5.6% for obesity, with the highest rates in the 10-year-olds (19.6% and 5.8%, respectively). While no gender differences were present in the youngest age group, the body mass index (BMI) during adolescence remained higher in boys but decreased significantly in girls. Male gender remained a risk factor through all calculations. Boys were overrepresented in schools with lower education levels and more often had BMIs ≥ 85th and ≥95th percentile. Higher parental education levels and lower parental BMIs were associated with lower BMIs of their offspring. Migration was an additional association factor for BMIs ≥ 85th percentile.

Low parental education levels, higher parental BMIs and migration background were associated with overweight and obesity in 10-year-olds. In adolescence, male gender and higher parental BMIs remained risk factors.