This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. ABSTRACT To facilitate and accelerate research in Bariatric Surgery, the National Institute of Diabetes & Digestive, and Kidney Diseases (NIDDK) established the Longitudinal Assessment of Bariatric Surgery consortium (LABS). The LABS research project, as originally conceived, focused only on adult subjects undergoing bariatric surgery. However, an ancillary studies mechanism was also established to support other related research projects. Teen-LABS is one such related project. The primary goal of this observational Teen-LABS study is to collect baseline characteristics and postoperative outcomes of adolescents who are undergoing bariatric surgery in an effort to assess safety and efficacy of bariatric surgery. By mirroring LABS data collection, the Teen-LABS study will also allow us to estimate the relative merits of early surgery compared to delayed surgery for extremely obese youth. This comparison will lead to a better understanding of the plasticity of important medical and psychosocial obesity-related comorbidities. Moreover, this study will provide critical scientific information to inform clinical decision-making regarding appropriate timing of bariatric surgery. I. HYPOTHESIS Severe obesity in adolescence is associated with medical and psychosocial impairments which may be more effectively treated with surgery during adolescence rather than later in adulthood. II. SPECIFIC AIMS Specific Aim 1: To determine whether health significantly differs between adolescents and adults seeking bariatric surgery and thereby determine whether there are potential age-related health benefits in performing bariatric surgery earlier rather than later in the lifetime. Specific Aim 2: To identify early (30 day) and intermediate term (1-2 year) health risks for adolescents and adults undergoing bariatric surgery. Specific Aim 3: To document the psychosocial status of adolescents and adults with extreme obesity before bariatric surgery and 1 and 2 years after surgery. Psychosocial status will be examined in three major domains: depressive symptoms, eating behaviors, and quality of life. Specific Aim 4: To obtain and store biospecimens (serum, plasma, whole blood, and liver tissue) for research related to the aims of this study, and for future use by this consortium and ancillary studies for research into the pathophysiology and genetics of obesity and obesity related issues. III. BACKGROUND AND SIGNIFICANCE Bariatric surgery is effective in treating extreme obesity in adults, and is most commonly used in the 5th decade of life. As more adolescents develop extreme obesity and seek bariatric surgery, our long term goal is to elucidate the health benefits and risks of surgical weight loss for adolescents. Our central hypothesis is that severe obesity in adolescence is associated with medical and psychosocial impairments which may be more effectively treated with surgery during adolescence rather than later in adulthood. This is based on our clinical observations that adolescents undergoing bariatric surgery 1) present with clinically occult manifestations of metabolic disease and have already developed significant health and psychosocial problems which are likely to worsen, 2) lose significant weight following bariatric surgery, and 3) experience significant improvement of a number of serious obesity-related conditions such as insulin resistance, myocardial hypertrophy, hypertriglyceridemia, and obstructive sleep apnea, depressive symptoms, and quality of life. However, compliance by adolescents with prescribed medical regimens may be limited and thus may adversely affect nutritional outcomes of bariatric surgery performed in adolescence. Thus, the purpose of this study is to elucidate for the first time the benefits and define complications for bariatric surgery performed in adolescence compared to the more standard approach of performing bariatric surgery in adulthood. Our Specific Aims are: 1) To determine whether health significantly differs between adolescents and adults seeking bariatric surgery and determine whether there is an age-related health benefit in performing bariatric surgery earlier rather than later in the lifetime; 2) To identify complications to be expected for adolescents and adults undergoing bariatric surgery; 3) To document the psychosocial status of adolescents and adults with extreme obesity before and after bariatric surgery. Adolescents will be recruited from several adolescent bariatric centers and a comparison cohort of adults will be recruited from adult bariatric centers participating in the Longitudinal Assessment of Bariatric Surgery (LABS). By comparison of key anthropometric features, metabolic features, sleep apnea indices, complications, nutritional and psychosocial status, we will begin to understand medical and psychological health outcomes of bariatric surgery using obesity duration as a moderating variable. This information will scientifically inform clinical decision-making regarding appropriate timing of surgery in the life-course of Americans whose health is increasingly threatened by extreme obesity.