Introduction: Patients with chronic kidney disease (CKD) suffer from significant survival and quality of life (QoL) as a consequence to the associated complications, symptom burden and comorbidities such as cardiovascular disease, cancer, infections, fatigue and pain. While previous studies have reported high symptom burden in CKD, they do not track changes in QoL over time due to cross-sectional nature of the data.  In this study, we bridge the gap longitudinally assessing the relationship between CKD progression and both overall and domain-specific QoL. Additionally, we identify factors that were predictive of QoL change.
Method: Data was sourced from the DETECT study, a prospective, multi-centre cohort study of 1,706 patients. We collated demographic information, medical history and the patients quality of life metrics measured using EQ5D-3L baseline and follow-ups at two and four years. The overall QoL was modelled using pairwise and mixed effect linear models and the domain specific QoL was modelled using mixed effect logistic regression. We identify predictive factors for quality of life (QoL) using a hybrid variable selection method that combines random forest with classical stepwise selection, leading to an analysis stratified by age.
Results: Our study established a significant association between QoL and the progression of chronic kidney disease (CKD) through its CKD stage, dialysis, and post-transplantation phases. Notably, patients post-transplant exhibited a significant improvement in QoL compared to those on dialysis (p = 0.02). We observed an association of reduced QoL with the females (p = 0.03) and cardiovascular disease (p ≤ 0.001). While our analysis did not identify a significant relationship between QoL and changes in CKD stages within each specific domain, we observed some differential trends within selected domain based on age stratified analysis. In particular, under the “Mobility” domain, we observed the QoL in younger patients (< 45 yrs) are less affected by CKD stages than older (> 65 yrs) patients. In addition, under the “Activity” domain, we observed QoL among patients between 45 and 65 years of age had a positive change in QoL compared to older patients. Across all five domains, other covariates identified as significant factors improving QoL included age, higher education level, and ethnicity. Notably, having a university-level education and certain ethnic backgrounds were significantly associated with improvements in QoL across all measured domains.
Conclusion: Although there is an overall association between QoL and changes in CKD stage, there was no strong overall association at each of the domains. Stratified by age, the analysis suggests varying relationships between QoL and CKD stages within specific age groups, particularly in the domains of “Activity”, and “Mobility”.