Changes in Adiposity without Impacting Bone Health in 9- to 12-Year-Old Children with Overweight and Obesity after a One-Year Family-Centered Lifestyle Behavior Intervention

Abstract
Background: Few family-centered lifestyle interventions (FCLIs) for children with overweight or obesity (OW/OB) have assessed regional adiposity and bone health. This study assessed changes in adiposity in 9- to 12-year olds with OW/OB in a 1-year FCLI. Methods: Children were randomized to FCLI (six registered dietitian-led sessions) or no intervention (Control, CTRL). The FCLI focused on physical activity, nutrition education, and behavioral counseling children with families present. Assessments occurred at baseline and every 3 months for 1 year to assess changes in waist circumference (WC), body mass index for age-and-sex Z-scores (BAZ), body composition (dual-energy x-ray absorptiometry), and cardiometabolic biomarkers. Mixed models were used to determine the effects of group and time or group-by-time interactions for all outcomes. Results: Sixty children (age: 11.1 ± 1.1 years, BAZ: 2.7 ± 0.6) were enrolled; 55 participants (n = 28 CTRL, n = 27 FCLI) completed the study. There were no between group differences from baseline to follow-up for any measure. The FCLI group had significant decreases in BAZ over 12 months (−0.18 ± 0.27, p = 0.03) but not CTRL (−0.05 ± 0.32, p = 0.92). WC and android fat mass did not change in FCLI (p > 0.20) but increased in CTRL (p < 0.02). Whole body bone area, content, and areal bone mineral density (aBMD) increased in both groups (p < 0.010); whole body aBMD Z-score decreased by 5.8% and 1.6% in CTRL and FCLI, respectively (p < 0.001). There were no significant within group changes in biomarkers. Conclusion: The FCLI resulted in small reductions in BAZ and a plateau in android fat mass, which suggest that FCLIs are suitable as an intervention for 9- to 12-year-old children with OW/OB. Clinical Trial Registration number: NCT01290016. Impact statement The family-based intervention for 9- to 12-year-old children that was based on Canadian dietary, physical activity, and sedentary behavior recommendations resulted in favorable changes in body composition, specifically reducing body mass index z-scores and changes in lifestyle behaviors without compromising bone health.