Biobehavioral Mechanisms of Activity and Loss of Control Eating in Children

The study involves a clinical interview, physical measurements, questionnaires, brain imaging (MRI), and a 10-day monitoring period during which participants will complete mobile phone surveys and physical activity will be monitored. Study sessions occur once a year for 3 years and will include virtual and in-person visits, each of which will last between 1-2 hours.

Procedure:

Screening - Study advertisements will direct interested parents/legal guardians of children to an online screening (via QR code). The online screening survey will be administered by REDCap and completed on their device. The screener will also include a document with mental health and eating disorder referral information because the screening process may raise awareness of these concerns. Potentially eligible families will be contacted via email or phone to set up a time for the study visit at UTD.

Study visits - Participants will complete 3 annual data collection visits that will be 12 months apart (Year 1, 2, and 3). During Years 1-2, participants and parents/guardians will complete a virtual session with researchers followed by an in-person visit at the UTD Brain Health Imaging Center (BHIC) where participants will complete the neuroimaging (fMRI) protocol. The Year 3 study visit will take place at Dr. Smith's research laboratory in the UTD Department of Psychology. During scheduling of study visits involving fMRI (Years 1-2), families will also be informed that participants will be asked to abstain from eating for 4 hours prior to fMRI to standardize procedures and capture representative physiological states prior to eating meals (during which inhibitory control, emotion regulation, and reward processing may influence subsequent eating behavior). We will provide mental health and eating disorder referral information to all families at study visits because the assessment process may raise awareness of concerns the parent was not previously aware of.

Informed by published ethical guidance for pediatric research developed for the NIH-funded Adolescent Brain and Cognitive Development (ABCD) study, parents will not be shown their child's individual interview or survey responses, with two exceptions: (1) current suicidal ideation or self-harm, and (2) eating disorder symptoms indicating the child is at serious medical or psychiatric risk (e.g., significantly low weight/weight loss or dangerous compensatory behaviors such as frequent purging). This will be operationalized as evidence of:

• BMI percentile below the 5th percentile for age/sex
• Rapid and significant weight loss
• Self-report during the clinical interview indicating compensatory behaviors (self-induced vomiting, laxative/diuretic misuse, fasting, compulsive exercise) occurring several times per week For consistency, and to protect the validity of adolescent self-report, we align the threshold of disclosing eating disorders with the same imminent/serious-risk standard as outlined in the ABCD study.

Year 1:

Virtual session - At the first virtual session, parents/guardians and participants will complete the initial informed consent and assent process with researchers virtually. During the informed consent process and in the consent form, it will also be explained that participants may be ruled out after enrollment if they do not meet study eligibility criteria (e.g., based on information provided during the clinical interview or their height/weight) or if MRI is not appropriate for participants due to contraindications. Following the informed consent process, participants' eligibility will be confirmed based on a clinical interview (Child Eating Disorder Examination administered virtually) and anthropometric (height/weight/waist circumference) measurements at the in-person visit. During the virtual session, participants and parents/guardians will complete self-report surveys online and receive mobile phone and accelerometer instructions.

In-person visit (UTD Brain Health Imaging Center) - Participants will complete a neuroimaging protocol and anthropometric assessments at the UTD Brain Health Imaging Center (accompanied by their parent/guardian), which will be scheduled within 2 weeks of the virtual session.

10-day data collection - Over the next 10 days after the in-person visit, participants will proceed through a 10-day data collection period in their daily life. This includes an ecological momentary assessment (EMA) protocol during which participants will be asked to proceed with their daily routines as normal. Participants will also wear an accelerometer across all 10 days. Staff will contact families by phone during the 10-day monitoring period to encourage compliance and address technical issues.

Year 2:

Virtual session - The consent and assent process will be repeated. Participants will repeat the clinical interview, and participants and parents/guardians will complete online surveys.

In-person visit (UTD Brain Health Imaging Center) - Participants will repeat the neuroimaging protocol and anthropometric assessments at the UTD Brain Health Imaging Center (accompanied by their parent/guardian), which will be scheduled within 2 weeks of the virtual session.

10-day data collection - Participants will repeat the 10-day data collection period.

Year 3:

In-person visit (UTD Psychology Department) - The consent and assent process will be repeated. Participants will repeat the clinical interview, anthropometric assessments, and participants and parents/guardians will complete online surveys.

10-day data collection - Participants will repeat the 10-day data collection period.

Data collection measures will include the following:

Anthropometric assessment (Years 1-3) - At each in-person study visit, height, weight, and waist circumference of the participant will be measured in duplicate using an electronically calibrated digital scale and professional stadiometer to the nearest 0.1 kg and 0.1 cm, respectively. Blind weight will be measured (i.e., they will not see their weight) to mitigate any distress or reactivity. These measurements will be completed at the BHIC in Years 1-2, and in Dr. Smith's research laboratory during Year 3.

Interview (Years 1-3) - Each year, participants will complete a clinical interview 9Child Eating Disorder Examination [ChEDE] diagnostic modules). This interview will be administered virtually in Years 1-2 and in-person at UT Dallas in Year 3. The ChEDE will be used to confirm eligibility at Year 1 and for descriptive purposes in Years 2-3.

Self-report questionnaires (Years 1-3) - Participants will report on their gender identity and sexual orientation, and they will complete a series of self-report questionnaires online.

Neuroimaging (Years 1-2) - In Years 1 and 2, participants will complete an fMRI protocol at the BHIC.

Prior to fMRI participants will also complete online surveys that assess exercise over the previous 24 hours, as well as current hunger state (using a visual analog scale from 0 [not hungry at all] to 10 [very hungry]) that will be considered as covariates in analyses. Participants will be asked to confirm they have abstained from eating for 4 hours prior to MRI. Parent/guardians will be asked to confirm eating abstinence, and imaging will be done at the end of the study session (i.e., after interview/questionnaire assessments) to ensure children have not eaten recently.

After completing pre-scan measures, participants will complete a practice session in the MR (magnetic resonance) simulator to familiarize participants with the scanning environment. Then they will complete the MRI protocol which includes complete three tasks in a randomized order while brain activity is being recorded with fMRI. Tasks will be projected on a screen located at the rear of the magnet and viewed via a head coil mirror. A response keypad will record task responses. The neuroimaging protocol will first acquire T2, T1, field map, and scout scans (~8-10 min) then two runs of the go/no-go task (~5 min/run), two runs of the visual food task (~6 min/run), and four runs of the emotion regulation task (~4 min/run), totaling 46-48 minutes of scanning time. Participants may take breaks as needed between runs.

Ecological momentary assessment (EMA; Years 1-3) - Across the 3 years, participants will complete an annual 10-day EMA protocol in their natural environment using an EMA application for smartphones. Participants will use a smartphone (either their own or one provided) to complete surveys, up to 4 times during non-school time on weekdays (morning wake-up time; 3:30pm-8pm) and up to 7 times on weekend days (9am-9pm). EMA measures will be collected using (1) signal-contingent reporting, which requires youth to complete assessments occurring at various times throughout the day in response to semi-random prompts, and (2) event-contingent reporting, which requires youth complete a survey after they engage in an eating episode. Semi-random prompts will be generated in stratified random sampling windows, with one prompt randomly occurring during each window. Youth will not complete random surveys on weekdays while at school to prevent classroom interruptions. However, they will be asked to record lunch on weekdays at school. At each semi-random signal, participants will also be prompted to report any missed eating episodes. Participants will receive information and training in the completion of EMA reports and behavioral tasks on the smartphone. Participants will be instructed not to complete entries at times when they feel they are not able or when safety is a concern. However, participants will be encouraged to complete the entry as soon as possible when able and will receive reminder prompts. Up to two reminder prompts will be sent within 30 minutes of the initial prompt, after which time the survey will close. Staff will call participants and their caregivers halfway through the protocol to give compliance feedback and to answer questions.

Ambulatory assessment (Years 1-3) - Physical activity and sedentary time will be measured using wrist-worn accelerometers. Participants will wear accelerometers continuously across 10-day monitoring period each year. Activity counts will be recorded in 10-second epochs. Participants will be provided with an accelerometer at each of the in-person visits, and parents/guardians will be provided with a self-addressed prepaid package to return the device after the 10-day monitoring period.

Inclusion criteria

• Can read and speak English.
• At-risk for loss of control eating will be over-sampled (representing minimum 30% of sample) to capture sufficient variability across time in loss of control eating, the online screener will include the Eating Disorders Examination Questionnaire-Short Parent Version (EDE-QS-P). At-risk for loss of control eating is defined on the EDE-QS-P as a global score at least 1 standard deviation above the mean EDE-QS-P score observed among parents of children without eating disorders (i.e., global score > 1.2).

Exclusion criteria

• Diagnosis of an eating disorder other than binge-eating disorder or subthreshold binge-eating disorder (i.e., binge-eating disorder of low frequency/limited duration), or presence of compulsive exercise as assessed by the Child Eating Disorder Examination.
• Health issues that limit physical activity.
• Intellectual disability (assessed with the Child and Adolescent Intellectual Disability Screening Questionnaire embedded within the online eligibility screener), which would interfere with completing ecological momentary assessment.
• Pregnancy.
• Acute suicidality (screened using item 9 on the Patient Health Questionnaire-Adolescent).
• Presence of conditions that would make fMRI unsafe (e.g., pacemaker), as assessed by an MRI screening form.
• Undergoing eating disorder or weight loss treatment.
• Classified as underweight by a body mass index percentile <5% adjusted for sex and age (body mass index z-score<-2.0).
• Schizophrenia, substance use disorders, severe neurological disorder (e.g., epilepsy, brain injury), or diabetes (per caregiver self-report).