Bone Health of Obese Adolescents During Weight Loss

Summary

The long-term goal of this proposal is to understand the impact of obesity and obesity treatment on bone health during adolescence and how to preserve it. The recent pediatric obesity epidemic raises important clinical and public health questions about the effects of childhood-onset obesity and its treatment on bone health. Osteoporotic fractures are a major cause of morbidity and mortality in the aged, and peak bone mass (PBM), achieved shortly after puberty, is a key determinant of bone strength and lifetime fracture risk. Given the current obesity epidemic, obesity treatment during adolescence will continue to be necessary. The benefits of pediatric obesity treatment are unquestionable. However, the potential detrimental effects of weight loss on bone density and dimensions are not known in adolescents and are the focus of this proposal.

This study will focus on the impact of pediatric-onset obesity and its treatment on bone health, using two approaches: comparing obese and non-obese adolescents and comparing obese adolescents before and after weight loss. We hypothesize that (a) compared to non-obese controls, obese adolescents have stronger bones, and that (b) bone strength of obese adolescents decreases during weight loss compared to usual care, which would suggest a need to promote bone health during successful weight loss in obese adolescents.

Conditions

• Pediatric Obesity

Interventions

BEHAVIORAL

Comprehensive behavioral weight control program

Participants will meet weekly for 12 weeks, then every other week for 12 weeks, and once a month thereafter through week 52. Adolescents and parents will receive manuals that provide lessons and homework assignments for each meeting. The program for the first 22 weeks includes the following topics: 1) the causes of obesity; 2) components of healthy nutrition; 3) self-monitoring of calories, physical activity, and inactivity; 4) stimulus control procedures; 5) coping with high-risk social or psychological situations that trigger excess eating; 6) increasing physical activity; and 7) minimizing inactivity. At each session, participants will submit their self-monitoring diaries and completed homework. Incentives for completion of self-monitoring tasks are an integral part of the behavior modification program and a small gift certificate will be given to subjects for successful completion at each intervention session.

OTHER

Individual 12-month nutrition education program

The other half of the participants (44 subjects) will be randomized to this arm of the intervention (usual care), which will also start in five waves. In contrast to the comprehensive behavioral weight control program, the nutrition education program will take place through individual appointments with a clinical dietician to reflect usual care and mimic the present approach used for the treatment of obese adolescents at the Children's Hospital of Philadelphia (CHOP) Nutrition Consultation. Parents will be required to take part in the consultations. The first consultation will last 60 minutes and the following consultations of 30 minutes will take place once a month for the first six months, then every other month for the second six months, as is the usual practice in our clinical setting.

Sponsors & Collaborators

• National Institutes of Health (NIH)

  collaborator NIH

• National Heart, Lung, and Blood Institute (NHLBI)

  collaborator NIH

• Children's Hospital of Philadelphia

  lead OTHER

Principal Investigators

• Babette Zemel, PhD · CHOP

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

NONE

Model

PARALLEL

Eligibility

Min Age

10 Years

Max Age

14 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2007-01-31

Primary Completion

2012-05-31

Completion

2012-05-31

Countries

• United States

Study Locations