Location: Children's Nutrition Research CenterTitle: Smaller weight changes in standarized body mass index in response to treatment as weight classification increases Author
Submitted to: Journal of Pediatrics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/16/2010
Publication Date: 4/1/2011
Citation: Johnston, C., Tyler, C., Palcic, J., Stansberry, S., Gallagher, M., Foreyt, J.P. 2011. Smaller weight changes in standarized body mass index in response to treatment as weight classification increases. Journal of Pediatrics. 158:624-627. Interpretive Summary: This study compares the differential efficacy of a school-based weight loss program for Mexican-American children who are overweight, obese or severely obese. Results indicate that the severely obese children demonstrate less benefit from the intervention compared with overweight and obese children. The authors believe that these severely obese children might have significantly more lifestyle barriers to overcome and less support to lose weight. Understanding the reasons for the decreased efficacy of this intervention with severely obese children can aid in tailoring the weight loss program to better address the factors that prevent adherence to a healthier lifestyle. Several factors, including metabolic regulation, the home and neighborhood environments, acculturation, and psychosocial factors, should be examined in order to improve the efficacy of school-based weight loss programs for children with higher weight status.
Technical Abstract: Our objective was to compare the differential efficacy of a weight loss program for Mexican-American children who are overweight, obese, and severely obese. Study participants were enrolled in an intensive weight loss intervention aimed at improving eating and physical activity behaviors with behavior modification strategies. Participants included 212 children (45% female) between the ages of 9 and 14 (mean = 12.0, standard deviation = 0.7). All participants were classified as overweight, obese, or severely obese. Repeated measures analyses revealed that children in the overweight, obese, and severely obese weight categories differed significantly in standardized body mass index (zBMI) decreases at baseline, 3, 6, and 12 months (F = 4.57, P < .01, partial eta * 2 = .06). Follow-up paired sample tests showed a significant change in zBMI from baseline to 3 and 6 months for children in the overweight, obese, and severely obese weight categories. However, at 12 months only the overweight and obese students continued to show significant improvement from baseline in zBMI. In conclusion,these findings suggest that an intensive behavioral weight loss intervention that has demonstrated efficacy for decreasing zBMI may have incrementally smaller effects for children as weight classification increases.