Among Multiple Mental Health Symptoms, Only Attention Deficit/Hyperactivity Problems Predict Poorer BMI Outcomes in Family-Based Behavioural Treatment for Youth With Severe Obesity.
Among multiple mental health symptoms examined, only Attention Deficit/Hyperactivity problems predicted poorer BMI outcomes in family-based behavioural treatment for youth with severe obesity, while self-worth, emotional dysregulation, internalizing, and externalizing problems were not associated with differences in BMI outcomes.
Key Findings
Results
Higher Attention Deficit/Hyperactivity (ADH) Problems scores were associated with smaller BMI reductions during family-based treatment.
Each one-unit T-score increase on the ADH problem scale was associated with 0.31 units less reduction in %IOTF25 (p = 0.02) and 0.01 units less reduction in BMIz (p = 0.03).
ADH Problems was the only mental health predictor among those tested that significantly predicted BMI outcomes.
A multivariate multilevel Bayesian linear mixed-effects model with repeated measures was used to estimate these effects.
The sample consisted of 90 participants aged 5.9–18.6 years (mean ± SD: 13.2 ± 3.1) enrolled in a 17-session FBT programme.
Results
On average, participants showed reductions in BMI measures over the course of family-based treatment.
Average change in BMI during FBT was -3.80 units for %IOTF25 and -0.08 units for BMIz.
Baseline mean %IOTF25 was 146 ± 13, indicating severe obesity well above the overweight threshold.
Baseline BMIz was 3.02 ± 0.52.
The sample was 58.9% girls with a mean age of 13.2 years.
Results
Self-Worth, Emotional Dysregulation, Internalizing Problems, and Externalizing Problems were not associated with differences in BMI outcomes.
Mental health predictors were assessed using the Self-Perception Profile for Children and the Child Behaviour Checklist.
Five mental health constructs were examined as predictors: Self-Worth, Emotional Dysregulation, Internalizing Problems, Externalizing Problems, and ADH Problems.
Only ADH Problems reached statistical significance among all predictors tested.
A multivariate Bayesian modelling approach was used, allowing simultaneous estimation of multiple predictors.
Methods
The study enrolled 90 youth with severe obesity in a 17-session family-based behavioural treatment programme.
Participants ranged in age from 5.9 to 18.6 years (mean ± SD: 13.2 ± 3.1).
58.9% of participants were girls.
Baseline mean percentage above the IOTF threshold for overweight (%IOTF25) was 146 ± 13.
Mental health was assessed at baseline using the Self-Perception Profile for Children and the Child Behaviour Checklist.
Conclusions
The authors recommend identifying children with higher ADH problems and incorporating additional family support strategies within FBT as a focus for further treatment development.
Large variability in FBT outcomes was noted as the motivation for examining mental health predictors.
The findings suggest ADH problems may be a clinically relevant moderator of treatment response.
The authors propose that standard FBT protocols may benefit from augmentation for youth with elevated ADH symptoms.
No other mental health symptom domains tested were identified as targets for treatment adaptation.
What This Means
This research suggests that among children and teenagers with severe obesity participating in a family-based weight management program, those with higher levels of attention deficit and hyperactivity (ADHD-type) problems tended to lose less weight than their peers. The study followed 90 young people aged approximately 6 to 19 years through a 17-session family-based behavioural treatment program, measuring changes in body mass index (BMI) alongside several aspects of mental health at the start of treatment. On average, all participants showed some improvement in BMI, but those with more attention and hyperactivity difficulties showed notably smaller reductions.
Importantly, the study also found that other mental health challenges — including low self-worth, emotional dysregulation, internalizing problems (like anxiety and depression), and externalizing problems (like aggression or rule-breaking) — did not significantly affect how well children responded to the weight treatment. This suggests that ADHD-related symptoms may have a specific and distinct influence on treatment outcomes, rather than mental health difficulties in general being the issue.
This research suggests that clinicians running family-based obesity treatment programs should consider screening for ADHD-type symptoms at the outset and potentially adapt their approach for children who score higher on these measures. Adding extra family support strategies tailored to the challenges that attention and hyperactivity difficulties create — such as difficulty following routines or impulse control around food — may help improve outcomes for this subgroup. The findings point to a potential area for treatment refinement rather than a reason to exclude children with these difficulties from care.
Skodvin V, Skjåkødegård H, Molde H, Wilfley D, Conlon R, Júlíusson P, et al.. (2026). Among Multiple Mental Health Symptoms, Only Attention Deficit/Hyperactivity Problems Predict Poorer BMI Outcomes in Family-Based Behavioural Treatment for Youth With Severe Obesity.. Pediatric obesity. https://doi.org/10.1111/ijpo.70147