children s growth and behavior study

Conditions: Obesity; Eating Behaviors; Healthy Volunteers

Summary: background: - studies show that many factors affect children's eating behavior and health. these include sleep, mood, thinking skills, and genetics. studying children over time may identify children at higher risk for eating-related health concerns. objective: - to understand how genes and environment influence eating behavior and health over time. eligibility: - children ages 8-17 in good general health. design: * screening visit 1: medical history, physical exam, body measurements, and questions. * 14 days: participants will wear a wrist monitor and answer smartphone prompts about eating and mood. they may give a stool sample. * screening visit 2: * body measurements. * saliva, urine, and blood samples. * heart tests. * meals provided (after fasting overnight). * questionnaires and interview. * behavior, thinking, and exercise tests. * x-ray of left wrist and full body.\ * some parents may have medical history, physical exam, and questions at screening visits. they may answer questions at the yearly visits. * participants will have up to 6 yearly visits. they will give a urine sample and body measurements, and repeat the x-rays. they will have questions and behavior and thinking tasks. they may give stool samples. visits will range from 3 to 8 hours. * participants may choose to participate in other studies: * stress and hormones, 1 visit: while resting, participants will give saliva samples and have their heart monitored. then they will do math. they will repeat the resting part, then do a computer task. * brain imaging, 2 visits: twice, participants will perform tasks with a magnetic cone on their head then answer questions. once, they will have an mri, lying still in a scanner with a coil on their head. before the first visit, participants will collect at-home saliva samples once a day for three days. during both visits, participants will perform tasks and answer questions that gauge their thinking skills and mood. * experiment 3 (sleep/fatigue): participants will complete 2 additional visits. during these visits, participants will complete a task on the computer for 2 hours, or watch a movie for two hours. after completion of the task/movie, they will answer questions and be provided with food. participants will be compensated for the time and inconvenience involved with completing study procedures.

this study aims to disentangle the varying disinhibited eating patterns, or eating behavior endophenotypes, that lead to excessive weight gain and obesity-related comorbidities in youth. extensive baseline evaluations, including three separate experimental paradigms, and annual follow-up assessments will assist with identifying biopsychosocial mechanisms that appear to increase risk for, and maintain, these eating behaviors and lead to weight gain. illumination of early risk factors for specific eating behavior endophenotypes and their associated health outcomes will inform the development of targeted interventions for pediatric obesity. participants for the current study will include 500 healthy obese and non-obese boys and girls (8 to 17yo at baseline) and their parents/caregivers. youth will first complete two visits in order to ensure study eligibility and to evaluate self-regulatory, motivational, and neurocognitive factors that appear to be salient to the development and maintenance of disinhibited eating behavior, including: psychological distress, sleep behavior, food reinforcement, reward sensitivity, executive functioning, attention bias, and a range of related genetic and physiological factors. eating behavior will be observed in the laboratory using several validated paradigms. for two weeks, participants will monitor their sleep using wrist actigraphy, as well as record their mood, eating behavior, and eating cognitions using smart phones (via ecological momentary assessment methods). youth will then be invited to complete up to three separate experimental paradigms designed to further elucidate cognitive, emotional, and physiological processes associated with disinhibited eating behavior. all participants will then complete annual evaluations of weight and adiposity for a total of six years, with more extensive evaluations of self-regulatory, motivational and neurocognitive functioning every three years. studying children and adolescents longitudinally will allow for examination of the independent and shared risk factors for pediatric disinhibited eating and excess weight. data from these evaluations will not only be used to test specific hypotheses, but will also be hypothesis-generating in that they will inform the development of additional empirical questions and subsequent experiments. thus, the current protocol will offer the flexibility to examine potentially critical contributions to weight gain in children as they continue their biopsychosocial development.

Eligibility criteria:
* inclusion criteria: volunteers will qualify if they meet the following criteria. * age 8-17 years (nb: children may continue to participate as adults during follow-up). * weight, height and bmi \>= 5th percentile for age and sex according to centers for disease control and prevention 2000 us standards. * cognitively capable of completing study procedures (fsiq \>= 70). * good general health based on a normal history and physical examination (with the exception of overweight and minor, well-controlled illnesses). exclusion criteria: individuals will be excluded (and provided treatment referrals as needed) for the following reasons: * history of major cardiovascular disease or any other serious obesity-related complication as assessed during history and physical exam. individuals with untreated or major illnesses relating to the endocrine and/or cardiovascular systems are excluded because these illnesses will likely influence outcomes. such obesity-related comorbidities include hypertension (defined by age- sex- and height- specific standards; and fasting hyperglycemia consistent with diabetes (fasting glucose \> 126 mg/dl). * presence of other major illnesses: renal, hepatic, gastrointestinal, most endocrinologic (e.g., cushing syndrome, untreated hyper- or hypothyroidism), hematological problems or pulmonary disorders (other than asthma not requiring continuous medication). non-serious medical illnesses, such as seasonal allergies, will be reviewed on a case-by-case basis. * regular use of any medication known to affect body weight or eating behavior (e.g., many medications prescribed for attention deficit hyperactivity disorder, or adhd). medication use for non-serious conditions (e.g., acne) will be considered on a case-by-case basis. * current pregnancy or a history of pregnancy. a negative pregnancy test before starting the study will be required for postmenarcheal girls. * current and regular use of tobacco products and/or alcohol. * a significant reduction in weight during the past three months, for any reason, exceeding 5% of body weight. * a history of significant or recent brain injury that may considerably influence performance on neurocognitive measures (i.e., any history of loss of consciousness \>=30 minutes associated with a head injury, any history of memory loss or hospitalization associated with a head injury, or \>=2 concussions within last year). * presence of any significant, full-threshold psychiatric disorder based on dsm criteria such as schizophrenia, bipolar disorder, alcohol or substance abuse, anorexia or bulimia nervosa, or any disorder that, in the opinion of the investigators, would impede competence or compliance or possibly hinder completion of the study. these individuals will not be permitted to enroll in the current study and will be referred for treatment. individuals who present with other psychiatric disorders, including sub-threshold psychiatric disorders, will be permitted to enroll in the study. sub-threshold psychiatric disorders include symptoms that do not meet diagnostic threshold based on the dsm criteria for mental disorders, but which are nevertheless significantly impairing or distressing. if, based on the opinion of the investigators, a participant requires treatment for his/her psychiatric symptoms, the individual will be referred for treatment. participants who develop any psychiatric disorder or significant psychiatric symptoms at any follow-up assessment during the study will not be excluded, but will be provided with treatment referrals. * any other condition in the child or parents/guardians that, in the opinion of the investigators, would impede compliance or possibly hinder completion of the study (e.g., significant learning disorder). additional exclusions for (optional) stool sample collection include: stool sample only: * diagnosis or history of inflammatory bowel disease, including ulcerative colitis or crohn's disease, celiac sprue, irritable bowel syndrome, or other inflammatory disorders of the intestine. * diarrhea within 1 week prior to sampling. * antibiotic use within 4 weeks prior to sampling. in addition, experiments 1 and 2 have specific additional exclusions: experiment 1 only: * regular use of medications that could influence autonomic or endocrine functioning, including alpha and beta blockers, oral contraceptives, or prescription pain medication. * scoring as "highly active" on the international physical activity questionnaire (due to decreased cortisol reactivity). experiment 2 only: * participants will be excluded if mri and meg is contraindicated (metal in/on body, braces, presence of non-organic \[e.g., cochlear\] implants or cerebral clips, permanent tattooed makeup or general tattoos that are recent and/or in a dangerous location on the body or made with colors whose content in iron cannot be definitely ruled out. * youth will be excluded if they are left-handed. all participants will receive a written explanation of the purposes, procedures, and potential hazards of the study. communication of this information and of the participant's assent as well as the consent of the parent or guardian will be documented in the medical record and copies of all signed documents given to each family. all participants will be informed of their right to withdraw from the study.

Keywords: stress response binge eating eating behavior obesity disordered eating natural history