Structured Low-level Intervention vs. Treatment as Usual Evaluated in a Randomized Controlled Trial for Adolescents With Extreme Obesity, Subproject 2

While obese youth are at high risk for co-morbidities, especially the extremely obese individuals rarely seek medical care. The underlying reasons are poorly understood, but patient inherent factors and the lack of adequate treatment options may play a role.

In this multicenter study, we aim to assess the acceptance and effectiveness of a manual based low key group intervention focusing on improving compliance and psychosocial functioning in adolescents with morbid obesity (BMI≥35kg/m2), in comparison to routine care. Youth with more moderate degrees of obesity (BMI 30-34.9kg/m2) will serve as an additional control group. The study is part of the Medical and psychosocial implications of adolescent extreme obesity - acceptance and effects of structured care", short: "Youth with extreme obesity Study (YES), which also comprises the recruitment and characterization of obese (BMI 30-34.9kg/m2) and extremely obese (BMI ≥ 35kg/m2) youth from different healthcare- and non healthcare settings, a structured prospective evaluation of adolescent bariatric surgery, economic assessments of the financial burden of extreme adolescent obesity on the healthcare system, and a long-term prospective observation study.

Based on the current state of knowledge, we will test the a priori ordered hirarchy of hypotheses:

1. The compliance rate 6 months after randomization is higher in subjects in the low key intervention group compared to the standard care group.
2. Covariant-adjusted changes in quality of life (assessed by DISABKIDS scale) between baseline and the 6 months follow up will be more pronounced in the low key intervention group compared to the standard care group.

The five participating university centers are distributed across 4 geographic regions in the North (Berlin), in the West (Essen/Datteln), in the East (Leipzig) and in the South (Ulm) of Germany, and will therefore render data that are representative of Germany as a whole. We will screen a 600 adolescents age 14 to 24.9 years (initially up to 21 years; this was changed in an amendment in February 2013) with extreme obesity (BMI ≥ 35 kg/m2) and 600 adolescents with obesity (BMI 30-34.9 kg/m2) over a 24 months period. A total of 350 subjects will be enrolled. Baseline assessments include an array of standardized questionnaires and validated instruments to assess health, psycho-social situation, psychiatric co-morbidities and health related quality of life, as well as an in-depth medical evaluation. Individuals who complete the baseline evaluations will be invited to participate in 6 group sessions over a 3 months period. Group assignment to the low key intervention vs. standard care group will be at random. The effects of the interventions on health related quality of life and psycho-social functioning will be assessed via questionnaires after 6 months. Subsequently, subjects will be invited to participate in additional components of YES.