Health-related quality of life in racial and ethnic minority adults with type 2 diabetes: validity and responsiveness of the EQ-5D-3L

Health-related quality of life (HRQL) assessment provides insights into the lived experiences of diverse populations. This study evaluated the convergent validity and responsiveness of the EQ-5D-3L in racial/ethnic minority populations with type 2 diabetes and elevated hemoglobin A1c (HbA1c). Secondary data from a clinical trial of a diabetes adherence support intervention for African-American and Latinx patients with type 2 diabetes (NCT02990299) were analyzed. Clinical (HbA1c, systolic blood pressure [SBP], body mass index [BMI]), psychological (brief 4-item diabetes distress scale [DDS4] for diabetes-related distress, 9-item patient health questionnaire [PHQ-9] for depressive symptoms), and HRQL (EQ-5D-3L) data were collected at baseline and every 6 months for 2 years. Convergent validity was assessed by examining the strength of associations between clinical/psychological measures and EQ-5D scores. A responder analysis using generalized estimating equation models was used to evaluate the EQ-5D's sensitivity to changes in clinical/psychological factors over time. Among 221 individuals analyzed, HbA1c and SBP levels did not differ across those reporting varying levels of problems in any EQ-5D dimension. Individuals with higher BMI were more likely to report problems with mobility, usual activities, pain/discomfort, and anxiety/depression. DDS4 scores were moderately correlated with EQ-5D anxiety/depression dimension and index score, while PHQ-9 scores were strongly correlated with both. EQ-5D index score was insensitive to improvements in clinical measures but sensitive to improvements in psychological measures over time. The EQ-5D-3L captured variations in BMI and psychological measures but not in HbA1c and SBP. This study provides HRQL estimates that can be compared with other populations or studies.