Stress and Health-Related Quality of Life in Adults With Type 1 Diabetes: The Mediating Role of Perceived Support and Treatment Adherence.

Aims: To examine the associations among diabetes-related stress, treatment adherence, perceived social support, and health-related quality of life (HRQoL) in adults with type 1 diabetes mellitus (DM1), and to explore the mediating roles of support and adherence in this relationship.

Design: A cross-sectional observational study using self-report standardised measures and mediation analysis.

Methods: A total of 772 Spanish adults with DM1 completed validated instruments measuring diabetes-related distress, perceived social support, treatment adherence, and HRQoL. Hierarchical multiple regression and serial mediation analysis (PROCESS Model 6, 10,000 bootstraps) were conducted, controlling for age, sex, and time since diagnosis.

Data sources: Not applicable (primary data collection, not a review).

Results: Diabetes-related stress was the strongest predictor of lower HRQoL. Perceived social support and treatment adherence also contributed significantly. Mediation analyses indicated that the impact of stress on HRQoL was partially mediated by perceived social support and, in sequence, by treatment adherence. The indirect path through social support alone and the sequential path involving both mediators were significant.

Conclusion: Stress and social support are critical in understanding and improving HRQoL in adults with DM1. Treatment adherence appears to be influenced by perceived support, highlighting an indirect mechanism linking stress to quality of life.

Implications for the profession and/or patient care: Healthcare professionals should integrate psychosocial assessments and interventions into routine diabetes care. Targeting stress reduction and enhancing social support may improve adherence and overall well-being in adults with DM1.

Impact: What problem did the study address? The study addressed the need to understand how psychosocial factors-specifically stress, perceived social support, and treatment adherence-contribute to HRQoL in adults with DM1. While prior research often focused on paediatric or clinical populations and rarely explored mediation models, this study sought to fill those gaps with data from a large community sample of adults. What were the main findings? The main findings indicate that diabetes-related stress is the most significant predictor of reduced HRQoL. This relationship is partially mediated by perceived social support and, sequentially, by treatment adherence. While stress directly affects HRQoL, its negative impact is also channelled through diminished social support and decreased adherence. The indirect effect through treatment adherence alone was not significant. Where and on whom will the research have an impact? The research has implications for adults living with DM1, particularly those in community settings outside of clinical supervision. It informs healthcare providers, diabetes educators, and policymakers on the importance of addressing emotional distress and strengthening support networks to improve both treatment adherence and overall quality of life.

Reporting method: This study adhered to the STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) guidelines for cross-sectional studies. All methods and results are reported in alignment with EQUATOR Network recommendations for transparent and rigorous research reporting.

Patient or public contribution: The study was conducted in collaboration with the Spanish Diabetes Federation (FEDE), which supported participant recruitment and dissemination through its affiliated associations. Patient input was incorporated throughout the study. A person with lived experience of type 1 diabetes contributed to the conceptual development of the research questions and the interpretation of findings. Their perspective helped ensure that the study design, choice of measures, and implications were relevant and meaningful to people living with the condition. This involvement supported a patient-centred approach to both the research and the manuscript preparation. Patients' participation as voluntary contributors was essential to the data collection process.