#2942 Feel good and live longer: association of baseline quality of life and changes over one year with mortality in patients on hemodialysis

Abstract Background and Aims Baseline measurement of quality of life (QoL) and changes over time are widely recommended in most hemodialysis (HD) guidelines. Besides the evaluation of the patients’ well-being, QoL assessment may provide useful information on relevant patient outcomes. The relationship of QoL with mortality in HD patients has been scarcely evaluated previously, almost exclusively in cross-sectional studies involving a small number of patients. The effect of time on HD in QoL scores and the impact of those changes on the mortality of HD patients remains to be defined. The aim of our study was to examine whether the physical (PCS) and mental (MCS) component summary scores of the quality of life short form health survey (KDQOL SF-36) were related to all-cause mortality in a sample of patients in maintenance HD, both at baseline as after one year of follow-up. Method We performed a multicentre, observational, prospective cohort study using data from an international HD provider database. All patients 18 years or older that voluntarily responded to the KDQOL SF-36 in 2021 and 2022 were included and followed for one year (from July 2022 until June 2023). The test was preferably self-administered, but patients could be assisted by a health professional during dialysis session when needed. The PCS and MCS scores of 2021 and 2022 were obtained and used to divide the population in two groups using the mean values of both scores. Subsequently, we formed three additional groups based on their composite scores dynamics over one year: one group with an increase of more than 5 points in the scores during that period (“increase”), one group with a decrease of more than 5 points (“decrease”) and a group with the remaining patients (“stable”). We used Kaplan-Meier and Cox regression analyses to evaluate survival, adjusted for age, gender, time on dialysis, diabetic status, Charlson comorbidity index, type of vascular access, dialysis blood flow and treatment time, kidney transplant status, mean arterial pressure, body mass index, hemoglobin, dialysis adequacy (eKt/V), plasmatic albumin, potassium and phosphorus. Results were presented as hazard ratios (HR) and 95% confidence intervals (95% CI) and a p-value below 0.05 was considered statistically significant. Results A total of 19,756 persons (53% of the eligible individuals) answered to both KDQOL SF-36 questionnaires in 2021 and 2022 and were selected for the study; of those, 1853 died during the evaluation period. The mean value of PCS was 38.2 ± 9.3 points in 2021 and 38.6 ± 9.6 points in 2022, whereas the mean value of MCS was higher (45.7 ± 10.2 points in 2021 and 46.1 ± 10.3 points in 2022). After one year, 31.1% showed an increase in PCS, 39.9% remained stable and 29.0% decreased the score. For MCS, we have observed an increase in 33.5% of patients, with 35.4% remaining stable and 31.1% decreasing after twelve months. In the survival analysis, a significant increase in mortality odds was observed in patients with composite scores below average, with higher HR being observed for PCS in both years and in the last survey before death for both scores (Fig. 1). Patients showing a significant decrease in PCS had a higher adjusted mortality HR (HR = 1.17; 95% CI, 1.04–1.31) when compared to both “increase” and “stable” patients, with no significant differences being documented in the HR of death between these two last groups (Table 2). Considering the MCS evolution, no difference in the mortality HR was observed between the three groups. Conclusion QoL physical and mental composite scores below the average value of the population were associated with a significant increase in mortality risk. After one year, an increase or a stable value of PCS, but not of MCS, correlated with a significant and independent reduction in mortality risk. These findings underscore the potential of QoL as a valuable patient-reported tool for guiding clinical interventions in the HD population to enhance patient survival.