Independent associations of mental health and diabetes complications with health‐related quality of life: Evidence from a cross‐sectional study

Abstract Aims Health‐related quality of life (HRQoL) is a key patient‐reported outcome in diabetes care, yet the extent to which somatic and psychological factors are associated with HRQoL remains unclear. This study examined how demographic, diabetes‐related, medical, and psychological factors were independently associated with HRQoL in adults with diabetes. Materials and Methods A cross‐sectional online survey was conducted among adults with diabetes in Germany (September 2024–February 2025). HRQoL was assessed using the EuroQol 5‐Dimension 5‐Level questionnaire (EQ‐5D‐5L). Participants also completed the PHQ‐8 for depressive symptoms, the problem areas in diabetes (PAID) scale, and the hypoglycaemia fear survey (HFS‐II). Clinical variables were self‐reported and included diabetes type, duration, HbA1c, body mass index (BMI), and complications. Tobit regression accounted for the censored EQ‐5D distribution. Blockwise multivariable models evaluated incremental explained variance across demographic, diabetes‐related, comorbidity, and mental‐health domains. Results Of 1581 invitees, 734 completed the EQ‐5D (mean age 56 ± 14 years; 73% type I). In multivariable analyses, female sex (β = −0.045), higher BMI (β = −0.029), diabetic foot syndrome (β = −0.078), neuropathy (β = −0.123), and elevated depressive symptoms (β = −0.212), diabetes distress (β = −0.069), and fear of hypoglycaemia (β = −0.085) were all independently associated with lower EQ‐5D utilities ( p < 0.01). Mental‐health variables explained a similar proportion of variance (≈22%) as diabetes‐related complications (≈20%). Mental health factors like depression, diabetes distress, and fear of hypoglycaemia showed highly significant associations with reduced HRQoL by up to 27%. Conclusions Both diabetes complications and mental health determine HRQoL in people with diabetes. Depression emerged as the strongest independent predictor reducing HRQoL by up to 21%. This underscores the importance of mental health for HRQoL. This findings highlight the relevance of integrating mental health assessment into diabetes management.