C MCKERCHER1, A VENN1, K SANDERSON1,2, M JOSE1,3,4, A NEIL1
1Menzies Institute for Medical Research, University of Tasmania, Hobart, Australia, 2School of Health Sciences, University of East Anglia, Norwich, UK, 3School of Medicine, University of Tasmania, Hobart, Australia, 4Royal Hobart Hospital, Hobart, Australia
Aim: To investigate agreement between the 3-level EQ-5D (EQ-5D-3L) and the Assessment of Quality of Life 4-dimension (AQoL-4D) questionnaire for assessing utilities in adults with pre-dialysis chronic kidney disease (CKD).
Background: CKD is associated with reduced health-related quality of life (HRQOL), particularly psychosocial QOL. While the EQ-5D is routinely used to assess HRQOL in adults with CKD, the AQoL-4D has greater breadth and good lower end sensitivity.
Methods: Utilities were assessed for adults (N=95, mean age 71.0±11.8 years) with pre-dialysis CKD (eGFR<30mL/min/1.73m²) using both instruments. Associations between utilities, and each utility value and sociodemographic, psychosocial and clinical outcomes including depression (Patient Health Questionnaire), anxiety (Beck Anxiety Inventory) and HRQOL (SF-36) were assessed using Spearman’s rho. Interchangeability/agreement was examined using Bland Altman analysis. Discriminatory attributes were investigated through floor/ceiling effects and dimension-to-dimension comparisons.
Results: Mean utility values were 0.75±0.20 (EQ-5D-3L) and 0.68±0.24 (AQoL-4D) (p<0.001). Both instruments detected statistically and clinically meaningful differences in utilities across self-report measures of depression, anxiety and HRQOL. Overall agreement between the two measures was moderate (r=0.56), with Bland-Altman analysis indicating wide limits of agreement (-0.38 to 0.48). A ceiling effect was observed with the EQ-5D-3L with 20 participants obtaining a utility of 1.00. For these participants, the corresponding mean AQoL-4D utility was 0.80 (range 0.06-1.00). Overall, the psychological well-being dimension provided the greatest variability.
Conclusions: There is moderate individual agreement between utilities assessed using the EQ-5D-3L and AQoL-4D in adults with pre-dialysis CKD. The AQoL-4D is more sensitive to variations in psychosocial QOL while the EQ-5D-3L is prone to ceiling effects. Prospective follow-up will allow a comparison of the sensitivity of these instruments to detect changes in psychosocial QOL over time.
Dr Charlotte McKercher is an epidemiologist and mental health researcher at the Menzies Institute for Medical Research. Her research in population health focusses the role of social, psychological and behavioural factors in the sequelae and progression of chronic kidney disease.