Association of dietary behaviors with health-related quality of life among primary and high school students in urban and rural Nanjing, China

  Objective  To explore the correlation between dietary behaviors and health-related quality of life (HRQoL) among primary and high school students in urban and rural regions of Nanjing municipality, China.

  Methods  Using multistage random cluster sampling, we recruited 4 498 students of grade 4 – 12 in 108 classes of 36 primary and junior/senior high schools in all administrative districts of Nanjing. On-site self-administered questionnaire survey and anthropometric measurement were conducted among the students during May – June 2018. Child Health Utility 9D – Chinese Version (CHU9D-CHN), Item-Specific Physical Activity Scale for Chinese Children and Adolescents (I-PASCA), and the Food Frequency Questionnaire were adopted in the survey. Multivariate linear regression model was used to analyze the association of dietary behavior with HRQoL among the students.

  Results  For the 4388 participants completed the survey (response rate = 97.6%), the mean value of HRQoL was 0.78 (standard deviation = 0.17). After adjusting for confounders and potential class-level clustering effects, the score of CHU9D decreased for the students with low frequency of vegetable intakes (mean difference MD = – 0.022, 95% confidence interval 95% CI: – 0.043 – – 0.001) and fruit intakes (MD = – 0.015, 95% CI: – 0.034 – 0.004) compared to those with high frequency of vegetable and fruit intakes; decreased CHU9D scores were also measured in the students with high consumption frequency of snack (MD = – 0.030, 95% CI: – 0.041 – – 0.020) and soft-drink (MD = – 0.024, 95% CI: – 0.034 – – 0.013) in comparison to those with low frequency of snack and soft-drink consumption; moreover, the results of multivariate analysis demonstrated that a – 0.22 (95% CI: – 0.03 – – 0.01) increment in the CHU9D score was correlated with each of the four unhealthy dilatory behaviors additively (low intake of vegetable and fruit and high consumption of snack and soft-drink) after adjusting for other variables.

  Conclusion  The intake frequency of vegetables and fruits are inversely associated with HRQoL, but the frequency of snack and soft-drink consumption are positively correlated to HRQoL; the four dietary behaviors are of synergistic effect on HRQoL among primary and high school students in Nanjing, China