How family interactions about lifestyle changes affect adolescents' possibilities for maintaining weight loss after a weight-loss intervention: a longitudinal qualitative interview study.

Aim: This study aims to examine how family interactions related to lifestyle changes influence adolescents' potential for maintaining weight loss after participating in a weight-loss treatment programme.

Background: Obesity among adolescents is a large and complex health problem worldwide. Family support is crucial if adolescents are to benefit from weight-loss intervention.

Design: Qualitative research interviews with families who participated in a weight-loss programme.

Methods: The sample consisted of 10 families selected among participants in a 1-year multidisciplinary family-based weight-loss programme. Three rounds of semi-structured interviews stretching over 5 years (2010-2015) were transcribed verbatim, then analyzed using Kvale and Brinkmann's framework for working with qualitative research interviews.

Findings: Five years after the intervention ended, we found that a family's interactions were a key factor in how the family handled challenges involved in changing its diet and increasing physical activity and that daily activities in modern families influenced their interaction, as activities demanded so much of the family that it was difficult to sustain the lifestyle changes necessary for the adolescent to maintain achieved weight loss. Supporting the adolescent was far more difficult than families expected; more time-consuming and also a cause of family conflicts. Siblings who did not need to lose weight played a major, but overlooked, role.

Conclusion: The family's interactions and its handling of lifestyle changes were important to the adolescent's maintained weight loss. It is fundamental that the entire family is supportive, regardless of family structure and these issues ought to be addressed in future interventions.