Evaluation of dyadic changes of parent-child weight loss patterns during a family-based behavioral treatment for obesity.

BACKGROUND: Family-based treatment (FBT) for children with overweight and obesity is a package that includes nutrition and physical activity education, as well as parenting and behavior therapy skills. To date, the majority of research suggests that one of the best predictors of child weight loss is parent weight loss. However, the bidirectional processes facilitating parent-child weight loss are not well understood. OBJECTIVE: To evaluate the strength and direction of parent-child weight-change patterns during a 6-month intervention with FBT for childhood obesity. METHODS: Parent-child weight change dynamics were evaluated using a bivariate multilevel approach. RESULTS: Significant positive weight reductions throughout treatment were observed among both parents and children (P's < .01 for both parent and child). In the model adjusting for the conditional influence of attendance over time, parents' initial weight loss was associated with subsequent weight loss by their child (B = 0.102, P < .05; d = 0.352) across the first 10 sessions. Child's weight loss also was associated with subsequent weight loss by their parent (B = 0.105, P < .01; d = 0.412) across the first 10 sessions. A small and negative effects of parents' weight loss on children and children's weight loss on parents from sessions 10 to 20 may have been reflective of slowed rates of weight loss as treatment progressed. CONCLUSIONS: Together these data suggest that parent-child dyads mutually influence weight loss in FBT. Future studies should leverage how to make best clinical use of these dynamic effects in the context of family-based interventions.