Plain language summary
The global spread of COVID-19 and subsequent lockdown measures have presented challenges worldwide. Previous research has highlighted the importance of six key lifestyle behaviours, including diet, physical activity, sleep, sedentary behaviour (including recreational screen time), alcohol use and smoking—collectively referred to as the ‘Big 6’—for the short-term and long-term health of adolescents. The aim of this study was to examine changes in the prevalence of six key chronic disease risk factors from before to during the COVID-19 pandemic, and also to explore whether differences over time are associated with gender and lockdown status. This study is a prospective cohort study among a large and geographically diverse sample of adolescents. The sample included 983 students (girls = 54.8%) from 22 schools. Results show that: - over the 2-year period, the prevalence of excessive recreational screen time, insufficient fruit intake and alcohol and tobacco use increased. - alcohol use increased more among girls compared to boys. - the prevalence of insufficient sleep reduced in the overall sample; yet, increased among girls. - being in lockdown was associated with improvements in sugar-sweetened beverages consumption and discretionary food intake. Authors conclude that supporting young people to improve or maintain their health behaviours, regardless of the course of the pandemic, is important, alongside targeted research and intervention efforts to support groups that may be disproportionately impacted, such as adolescent girls.
OBJECTIVE To examine changes in the prevalence of six key chronic disease risk factors (the "Big 6"), from before (2019) to during (2021) the COVID-19 pandemic, among a large and geographically diverse sample of adolescents, and whether differences over time are associated with lockdown status and gender. DESIGN Prospective cohort study. SETTING Three Australian states (New South Wales, Queensland and Western Australia) spanning over 3000 km. PARTICIPANTS 983 adolescents (baseline Mage=12.6, SD=0.5, 54.8% girl) drawn from the control group of the Health4Life Study. PRIMARY OUTCOMES The prevalence of physical inactivity, poor diet (insufficient fruit and vegetable intake, high sugar-sweetened beverage intake, high discretionary food intake), poor sleep, excessive recreational screen time, alcohol use and tobacco use. RESULTS The prevalence of excessive recreational screen time (prevalence ratios (PR)=1.06, 95% CI=1.03 to 1.11), insufficient fruit intake (PR=1.50, 95% CI=1.26 to 1.79), and alcohol (PR=4.34, 95% CI=2.82 to 6.67) and tobacco use (PR=4.05 95% CI=1.86 to 8.84) increased over the 2-year period, with alcohol use increasing more among girls (PR=2.34, 95% CI=1.19 to 4.62). The prevalence of insufficient sleep declined across the full sample (PR=0.74, 95% CI=0.68 to 0.81); however, increased among girls (PR=1.24, 95% CI=1.10 to 1.41). The prevalence of high sugar-sweetened beverage (PR=0.61, 95% CI=0.64 to 0.83) and discretionary food consumption (PR=0.73, 95% CI=0.64 to 0.83) reduced among those subjected to stay-at-home orders, compared with those not in lockdown. CONCLUSION Lifestyle risk behaviours, particularly excessive recreational screen time, poor diet, physical inactivity and poor sleep, are prevalent among adolescents. Young people must be supported to find ways to improve or maintain their health, regardless of the course of the pandemic. Targeted approaches to support groups that may be disproportionately impacted, such as adolescent girls, are needed. TRIAL REGISTRATION NUMBER Australian New Zealand Clinical Trials Registry (ACTRN12619000431123).