Body weight trends in adolescents of Central Italy across 13 years: social, behavioural, and psychological correlates

Aim The study aimed to determine trends in the prevalence of underweight, overweight, obesity and their putative risk factors in different cohorts from a representative population of adolescents in Central Italy. Subject and methods After random sampling, five cohorts of adolescents attending public high schools – aged 14 to 18 years – were evaluated from 2005 to 2018 (n: 25,174). Collected information included self-reported body mass index (BMI), descriptors of family environment, eating behaviour, physical activity, screen use, bullying victimisation, sexual behaviour (age at first intercourse, number of partners) and perceived psychological distress. For these data, between-cohort prevalence differences were used to esteem prevalence variations across time. In the 2018 cohort, the association between these factors and body weight was evaluated through multinomial regressions with sex-specific crude relative risk ratios for different BMI categories. Results An increased prevalence of overweight was observed for both boys and girls. The study outlined a transition towards higher parental education and unemployment, reduced soft drinks consumption and higher psychological distress. Sex-specific changes were observed for physical and sexual activity, and a rising percentage of girls reported being bullied and distressing family relationships. Parental education and employment, together with physical activity, confirmed to be protective factors against pathological weight. The latter clustered with reduced soft drinks consumption, bullying victimisation, early sexual activity, worse family relationships and higher distress. Conclusion An increased prevalence of both overweight and underweight was observed across time. Economic factors associated with unemployment and changes in behavioural patterns may have contributed to this trend.