Determinants of health‐related quality of life in adults with type 1 diabetes: The predominant role of sleep among lifestyle parameters

AIM: To examine the effect of lifestyle parameters on health-related quality of life (HrQoL) in people with type 1 diabetes (PwT1D); specifically, whether aggregated lifestyle indices or individual components better explain variations in HrQoL. METHODS: Dietary intake, physical activity, sleep habits and HrQoL were evaluated using validated questionnaires. Diet quality was assessed with the MedDiet and PURE Diet Scores. Two composite healthy lifestyle indices (MLI: Mediterranean Lifestyle Index, PLI: PURE Lifestyle Index) were constructed based on diet, physical activity, smoking and sleep. Participants were classified according to overall quality of life (OQoL) as worse, average or better. RESULTS: A total of 236 PwT1D participated [median age 38.0 (25.0, 48.8) years; 42.4% men; median T1D duration 19.0 (10.0, 29.0) years; HbA1c 7.4% (6.8, 8.2)], with 24.2%, 52.1%, and 23.7% reporting worse, average and better OQoL, respectively. After adjustments for sociodemographic and clinical factors, higher MLI and PLI scores were associated with greater odds of better OQoL (MLI: OR = 1.41, 95% CI: 1.15-1.72; PLI: OR = 1.40, 95% CI: 1.15-1.70). These associations became non-significant when the sleep component was excluded. In individual analyses, poor sleep quality was the only lifestyle parameter associated with OQoL (OR = 0.55, 95% CI: 0.45-0.68), physical (OR = 0.89, 95% CI: 0.82-0.98) and mental (OR = 0.73, 95% CI: 0.65-0.82) components. CONCLUSION: Lifestyle indices (MLI, PLI) were associated with better compared to worse HrQoL in PwT1D; however, this was entirely driven by sleep quality, with poor sleep linked to lower physical, mental and overall HrQoL.