Group-based interventions to reduce diabetes distress in adults with type 1 diabetes: A rapid realist review of the Reduce and TunedIn interventions

AIMS: Diabetes distress is highly prevalent among adults with type 1 diabetes, yet remains under-recognised and rarely addressed in routine diabetes care. This rapid realist review aimed to identify how, why, for whom, and in what contexts group-based interventions reduce elevated diabetes distress in adults with type 1 diabetes, to inform the co-adaption of a new diabetes distress intervention in the UK ('D-Stress Reduce').

METHODS: Following established rapid realist review methods, we synthesised evidence from 27 papers relating to two existing diabetes distress interventions and the psychological and social theories underpinning them. Data extraction and analysis focused on identifying contexts, mechanisms and outcomes, supported by stakeholders including methodological experts and programme architects.

RESULTS: Seven programme theories were generated and articulated through 20 'If-Then-Because' statements. Key theories highlighted emotional regulation, peer support and person-centred facilitation in reducing diabetes distress. Other theories included regular assessment and follow-up, motivation for action, and empowerment in self-management. The review found that interventions were most effective when adults with type 1 diabetes reported feeling emotionally safe, listened to and respected, and when group facilitators shifted from directive, hierarchical communication styles to collaborative approaches. Contextual factors, such as group composition, facilitator skill, and individual readiness for change influenced outcomes.

CONCLUSIONS: This review provides a theory-driven foundation for developing, implementing and evaluating a new co-adapted diabetes distress intervention in the UK ('D-Stress Reduce') and highlights multiple components that can be addressed to improve the care pathway and group-based experience.