Psychosocial outcomes of the Fast Track to Health clinical trial in adolescents with obesity

Introduction: Adolescent obesity requires effective and accessible treatment. Intensive dietary interventions may be used as adjunctive therapy to behavioral interventions, and lead to weight loss. The effects of behavioural interventions on psychosocial outcomes are mixed, and the impact of intensive interventions with shifts away from normal eating habits and social norms is not clear. Methods: Adolescents (13-17years) with obesity and ≥1 complication participated in a 52-week RCT, conducted 2018-2023 (ACTRN12617001630303). The intervention compared a 4-week very low energy diet followed by intermittent or continuous energy restriction (48weeks). Anthropometry and psychosocial health were assessed at baseline, weeks-4, -16, and -52 including Dutch Eating Behaviour Questionnaire (DEBQ), Rosenberg Self-Esteem Scale (RSE), Weight Bias Internalization Scale (WBIS), Body Appreciation Scale (BAS), and Depression Anxiety and Stress Scale (DASS). Intention to treat analysis using linear mixed models investigated changes over time between intervention groups. Results: 141 adolescents (70 female) were enrolled and 97 (48 female) completed the intervention. There were significant reductions in external eating (DEBQ, p<0.001), weight bias internalization (WBIS, p<0.001), anxiety (DASS, p<0.001), and stress (DASS, p=0.082), and significant increases in self-esteem (RSE, p<0.001) and body appreciation (BAS, p<0.001) in both groups. There were increases in dietary restraint (DEBQ, p=0.595), and decreases in emotional eating (DEBQ, p=0.645) and depression (DASS, p=0.381) which returned to baseline by the end of intervention. Reductions in BMIz were significantly associated with improvements in emotional eating (r=0.215, p=0.046, n=87) and body appreciation (r=-0.235, p=0.027, n=88). Conclusion: Intensive interventions incorporating dietary and behavioural components were associated with improvements in psychosocial health among adolescents with obesity associated complication.