BACKGROUND: Though recent data suggest that multidisciplinary outpatient interventions can have a positive effect on childhood obesity, it is still unclear which program components are most beneficial and how they affect quality of life (QoL). The aim of this study was to determine if a 1-year multidisciplinary, family-centered outpatient intervention based on social cognitive theory would be effective in (i) preventing further increases in BMI and BMI z-score, and (ii) improving QoL in obese children and adolescents.

METHODS: Obese children and adolescents 8-17 years of age and their families participated in this 1-year longitudinal pilot intervention study. The intervention consisted of fifteen 90-minute educational sessions led by a dietitian, exercise specialist, and social worker. Anthropometric measures, body composition, and QoL (Pediatric Quality of Life Inventory 4.0), were assessed at baseline, 3 months, and 12 months. Laboratory values were measured at baseline and 12 months. The primary outcome measures were change in BMI and BMI z-score, secondary outcome measures included change in QoL and body composition. A paired sample t-test was used to assess within-group differences and 95% confidence intervals were reported for the mean differences.

RESULTS: 42 obese children and adolescents (21 girls) completed the 1-year intervention (mean age 12.8 ± 3.14 years). Mean baseline BMI was 31.96 ± 5.94 kg/m(2) and BMI z-score was +2.19 ± 0.34. Baseline QoL (self-assessments and parental assessments) was impaired: mean baseline scores were 74.5 ± 16.5 and 63.7 ± 19.4 for physical functioning and 69.0 ± 14.9 and 64.0 ± 18.3 for emotional functioning, respectively. At 12 months, BMI z-score had decreased (-0.07 ± 0.11, 95% CI: -0.11 to -0.04). BMI (0.80 ± 1.57 kg/m(2), 95% CI 0.31 to 1.29) and fat-free mass (4.02 ± 6.27 kg, 95% CI 1.90 to 6.14) increased, but % body fat and waist circumference did not. Both the parent-reported physical (11.3 ± 19.2, 95% CI 4.7 to 17.9) and emotional (7.7 ± 15.7, 95% CI 2.3 to 13.0) functioning QoL scores and the children's self-reported physical (5.3 ± 17.1, 95% CI 0.5 to 11.1) and emotional (7.9 ± 14.3, 95% CI 3.2 to 12.7) functioning scores significantly improved.

CONCLUSIONS: Following a 1-year intervention, the participants' BMI z-scores and QoL improved, while other adiposity-related measures of body composition remained unchanged.

TRIAL REGISTRATION: UMIN Clinical Trials Registry UMIN000015622 .