Development and feasibility testing of a physical activity intervention for youth with anxiety and depression: a study protocol.

Background: Anxiety and depressive disorders in children and adolescents are highly prevalent and account for more than half of all youth psychiatric disorders. Left untreated, anxiety, and depression lead to numerous detrimental outcomes, including reduced quality of life, psychiatric, and somatic comorbidity and even reduced lifespan. This puts a large strain on child and adolescent mental healthcare services (CAMHS) to provide effective treatments. However, even when provided the best evidence-based treatment, between 40-50% of patients continue to report significant symptom burdens. Thus, there is an immediate need for supplemental and/or new treatment approaches. Physical activity as a supplementary treatment may be such an approach. However, research investigating this approach within this population is scant. This protocol paper describes the development and feasibility trial of a physical activity-based intervention targeting anxiety and depressive symptoms in youth treated in CAMHS.

Methods/design: The study is based on the UK Medical Council Research Framework (MRC) for developing and evaluating complex interventions. Feasibility and acceptability of the physical activity intervention (confident, active, and happy youth) will be evaluated in an uncontrolled open-label trial using qualitative and quantitative data. Twenty youths with anxiety and/or depressive symptoms will be recruited. Acceptability of assessment procedures, the intervention, and perceived benefits and barriers to participation will be assessed, and qualitative interviews with participants, caregivers, and referring specialists will explore contextual and practical factors associated with intervention delivery. Physical activity will be measured using the Actigraph GT3X+ monitor at baseline, and post-intervention and change in anxiety and depression will be assessed.

Discussion: This study will contribute to the development of supplementary physical treatment interventions for youth with anxiety and depression in contact with CAMHS. The goal is to examine new avenues of treatment that ultimately may improve upon current treatment outcomes of anxiety and depression. This work will be in preparation for a future definitive randomized controlled trial (RCT) of this approach, in line with the MRC Framework.

Trial Registration: ClnicalTrials.gov, NCT05049759 . Registered on August 19, 2021. Retrospectively registered.