Effect of multidimensional lifestyle interventions on metabolic risk reduction in children: a cluster randomised controlled trial

Abstract

Few clinical trials have investigated lifestyle intervention effect on metabolic health in children. The study aimed to examine the effect of diet and physical activity intervention on the reduction of clustered metabolic risk score (CMRS) in children and moderators and mediators of the intervention effect. A multicentre, clustered randomised controlled trial was conducted with examination conducted at baseline and after intervention over one year. 7110 children (49.7% girls) with a mean of 9.06 (95% CI: 9.03, 9.09) years were included in the analysis. In Beijing, each three schools were randomly assigned to diet-only, physical activity-only intervention and control groups. In five other urban cities, each 15 schools were randomly assigned to comprehensive intervention and control groups. CMRS was computed by summing the Z scores of % fat mass, systolic blood pressure, fasting glucose, ratio of cholesterol to high-density lipoprotein, and triglyceride. Compared with controls (n = 2808), children in the comprehensive intervention group (n = 2848) had more reduction in CMRS (multivariate-adjusted mean difference (95% CI): -0.49 (-0.85, -0.14)). The body mass index (BMI) reduction explained 7.3% (95% CI 2.8%-18.1%) of the total intervention effect. The intervention was more effective in children with higher birthweight, lower parental BMI, or complete parental data. Diet-only or physical activity-only intervention had non-significant effects on CMRS reduction. Our multidimensional comprehensive intervention resulted in significant reduction in CMRS in primary school children and this effect was modified by birthweight, parental BMI, and parental involvement. A minority of metabolic risk reduction was mediated through BMI. Clinical Trial Registry number and website: ChiCTR-PRC-09000402, URL: http://www.chictr.org.cn.

Keywords: Clustered metabolic risk; Lifestyle intervention; Mediation; Moderation; Obesity.