Association Between Diet Quality and Cardiometabolic Risk Factor Clustering Stratified by Socioeconomic Status Among Chinese Children

Background Few studies have evaluated the long-term relationship between diet quality and cardiometabolic risk factor clustering among children. The moderating effect of socio-economic status (SES) is of interest. Objective To investigate the association between diet quality with cardiometabolic risk among Chinese children and to explore the moderating effect of SES. Design In this cohort study, 5 waves (1997-2009) of the China Health and Nutrition Survey were used. Diet quality was measured by a modified version of the Chinese Children Dietary Index (mCCDI) based on Dietary Guidelines for Chinese. Participants Children between the ages of 7 and 17 (n = 2903) who completed at least 2 surveys were included. Those who missed measures or had hypertension or diabetes at baseline were excluded. Main outcome measures The fasting blood samples were collected in 2009. Waist circumference (WC) and blood pressure (BP) were measured in each survey. Statistical analysis performed A continuous cardiometabolic risk score (MetScore) was derived by a confirmatory factor analysis of 5 components: WC, BP, glucose, tri-glycerides, and high-density lipoprotein cholesterol. Considering the latency period of the effect of behaviors, the mCCDI was lagged by the period between surveys. Linear regression was used to analyze the association of mCCDI with MetScore and its components. Mixed effect linear regression and lagged mCCDI were used for WC and BP models. Results Higher mCCDI was independently associated with a lower MetScore at followup (beta: -.11; 95% CI: -.18 to -.04). Higher lagged mCCDI over time was associated with a lower WC z score overall (beta: -.05; 95% CI: -.08 to -.01) and among children in the low SES group (beta: -.09; 95% CI: -.14 to -.04) but not those in the high SES group. When examining the 15 mCDDI components separately, scores for 5 components: more grains, vegetables, soybeans and its products; less sugar-sweetened beverages; and more diet variety were significantly associated with a lower MetScore. Conclusions Among Chinese children, higher diet quality measured by mCCDI was independently associated with a lower MetScore at follow-up.