Effect of Stimulant Medication on Loss of Control Eating in Youth With Attention Deficit/Hyperactivity Disorder

Loss of control eating (LOC-E) in youth predicts the later development of full syndrome eating disorders, such as binge-eating disorder (BED), and therefore, could be a relevant target for prevention interventions. Children with attention deficit/hyperactivity disorder (ADHD) are at higher risk of experiencing LOC-E than healthy controls, and there is evidence that related neurocognitive predisposing factors, such as impulsivity and dysfunctional reward processing, are associated with the pathogenesis of LOC-E. Therefore, it is pertinent to examine whether modifying these neurocognitive symptoms influences LOC-E and the subsequent development of eating disorders. Stimulants are an efficacious treatment for impulsivity in youth with ADHD and have been shown to improve symptoms of binge eating in adults; however, studies have not prospectively explored the effect of stimulants on LOC-E in youth. To explore this gap, the investigators aim to collect prospective observational data in a clinical setting to measure change in LOC-E episodes and secondary outcomes in youth aged 8 to 13 years old with ADHD and LOC-E who are treated with stimulants. The investigators will collect outcome measures prior to stimulant initiation (baseline) and 3 months after stimulant initiation.

This study will use a prospective, observational case series design. Participants will be a prospective cohort sample of males and females aged 8 to 13 years old, and their parents/guardians, who have been referred to either: a) the Atlantic ADHD Centre in Dartmouth, Nova Scotia; b) the Mill Cove Medical Pediatric Clinic in Bedford, Nova Scotia; c) the general pediatrics outpatient clinic at IWK in Halifax, Nova Scotia; or d) the Beyond ADHD virtual clinic based out of New Brunswick. The research team will be based out of the Nova Scotia Health Authority Eating Disorder Clinic (Abbie J Lane Building; QEII Health Sciences Centre) in Halifax, Nova Scotia.

Due to the duration and limited success of recruitment, our team has decided to decrease the sample size. As of June 2024, our study will decrease from an estimated sample size of 40 parent-child pairs (80 total participants) to 10 (20 total). This will allow us to complete the study within the expected timeline and design a study that addresses the slower than expected recruitment (e.g., expand future recruitment sites).

Clinicians in the Atlantic ADHD Centre routinely pre-screen for LOC-E, using the Child Brief Binge-Eating Questionnaire (CBBEQ; Franklin et al., 2019), as part of their standard clinical assessment (see Appendix for schedule of assessments). This assessment also includes a psychiatric history by an ADHD expert and cognitive data using a validated Continuous Performance Test (CPT). Patients who are diagnosed with ADHD and pre-screen positive for LOC-E (score of 8 or above on CBBEQ), and who receive a recommendation to start a stimulant medication and intend to initiate the stimulant, will be invited to a consent and screening visit. Prescreening data collection is standard practice at the centre (i.e., relevant personal health information and scale-based outcomes) and will not be recorded for the study, as consent will not have been obtained. However, clinic staff will record the following non-personal health information that can be used in a participant flow diagram for study purposes: a) number of positive and negative pre-screens, and b) number of patients who are interested or not interested in being contacted by a research team member to learn more about the study.

At the clinics, parents/guardians and children who are interested in participating will be provided with an information sheet about the study. The parent/guardian will be asked to provide written consent to be contacted via their email or telephone by the research team. Parents/guardians who consent to being contacted will be sent a link to the electronic consent form (on REDCap). Once they have reviewed and signed the consent form, they will be asked to answer screening questions about their child (see Inclusion/Exclusion Criteria below). The parent/guardian of eligible potential child participants will be contacted about booking a Screening/Baseline interview, which will be held via Zoom for Healthcare or in-person at the Nova Scotia Health Authority Eating Disorder Clinic.

After a child is diagnosed with ADHD, clinicians at the Mill Cove Medical Pediatric Clinic, the general pediatrics outpatient clinic at IWK, and Beyond ADHD generally prescribe stimulant medications themselves. At the Atlantic ADHD Centre, children are referred back to their general practitioner to initiate a stimulant medication. If a child's scheduled appointment with their general practitioner to initiate a stimulant (which will occur naturalistically outside of the study context) is \>2 weeks away, they will complete an initial Screening interview with a research assistant, and if they are found eligible a separate Baseline interview will be booked within 1-2 weeks of their appointment with the general practitioner. Child participants who are scheduled to see their general practitioner within the next 1-2 weeks will complete the Screening and Baseline measures with a research assistant within the same interview, provided they are found eligible after the screening portion of the interview.

At the start of the Screening interview, a research assistant will review the informed consent form with parent/guardian. Verbal consent to participate will be obtained from the parent/guardian. Then, the research assistant will conduct the assent discussion with the child, by following the Assent Script, and will complete the Assent Form. Verbal assent to participate will be obtained from the child.

This study will obtain baseline and outcome measurements through a series of assessments at 2 time-points: prior to initiating a stimulant (i.e., Baseline) and 3-months post initiation (i.e., follow-up). These assessments will be administered by a trained research assistant.

Within-patient standardized effect size information (i.e., Cohen's d and 95% confidence intervals) from Baseline to 3-Month Follow-Up will be calculated for LOC-E episodes and all secondary outcomes. Clinical outcome data will be analyzed for all youth who remain on a stimulant for the 3-month duration. Descriptive statistics (e.g., means and standard deviations) will be used to report demographic information, medication doses, adverse events, and frequency of medication discontinuation. If available, reasons for medication discontinuation and loss to follow-up will be documented. Given the case series design, there will be no a priori power analysis.

Eligibility Criteria:
Inclusion Criteria:

* Youth 8 to 13 years of age
* Able to provide informed consent
* Meet DSM-V diagnostic criteria for ADHD
* Experienced at least 3 episodes of LOC-E during the past 3 months, accompanied by some degree of distress and 2 of the 5 behavioural symptoms associated with LOC-E

Exclusion Criteria:

* Currently receiving treatment for overweight
* Taking medication with effects on eating behaviour
* Insufficient English language skills