Lifestyle-related behaviors and health-related quality of life among children and adolescents in China

Purpose To investigate associations of five typical lifestyle-related behavioral risk factors (insufficient physical activity, prolonged screen viewing, deprived sleeping, consumption of fast food and sugar-sweetened beverage) with health-related quality of life (HRQoL) among school students in China. Methods Students aged 9–17 years (grades 4–12) were randomly selected from primary and high schools in Nanjing, China, to participate in this cross-sectional study in 2018. The outcome variable, HRQoL, was assessed using the Child Health Utility 9D (CHU9D) instrument and scored from 0 (worst) to 1 (best). Physical activity (including screen viewing and sleeping) and dietary intake were measured using a validated Physical Activity Scale and Food Frequency Questionnaire, respectively. Lifestyle-related behaviors were categorized as sufficient/insufficient or no/yes, and their associations with HRQoL were assessed using mixed-effects linear regression models. Results Overall, 4388 participants completed the questionnaire (response rate = 97.6%). Students with insufficient physical activity [mean difference (MD) = − 0.03; 95% confidence interval (CI) = − 0.04, − 0.01], prolonged screen time (MD = − 0.06; 95% CI = − 0.07, − 0.04), insufficient sleeping time (MD = − 0.04; 95% CI = − 0.07, − 0.02), consumption of sugar-sweetened beverage (MD = − 0.02; 95% CI = − 0.03, − 0.01) or fast food intake (MD = − 0.03; 95% CI = − 0.04, − 0.02) reported significantly lower HRQoL scores. When considered additively, each additional lifestyle-related risk factor was associated with an average decrease of 0.03 units (95% CI: − 0.03, − 0.02) CHU9D score. Conclusions For Chinese students, HRQoL was positively associated with physical activity and sleep duration, but negatively with screen time and consumption of sugar-sweetened beverage and fast food. Moreover, lifestyle-related behaviors may have an additive effect on HRQoL.