Peritoneal Dialysis Vs Hemodiafiltration for Elderly Patients over 75 Years with Com CKD Stage 5D: A Prospective Cohort Study

Abstract

Background: Chronic Kidney Disease (CKD) is a growing global public health concern, with diabetes, systemic arterial hypertension, and aging as key risk factors. A significant portion of the elderly population undergoes hemodialysis (HD), and prior studies have compared patient outcomes between peritoneal dialysis (PD) and HD. Despite the benefits of PD, such as home-based treatment and greater autonomy, its use has increasingly declined. More recently, hemodiafiltration (HDF) has emerged as an alternative to HD, showing improved outcomes. However, no studies have compared HDF with PD in elderly patients. Objective : This study aimed to compare mortality outcomes in elderly patients (≥75 years) newly initiated on renal replacement therapy (RRT) with PD or HDF. Methods : This prospective observational cohort study included patients aged ≥75 years who started PD or HDF at two hospitals (Hospital Sancta Maggiore - Liberdade and Botucatu Medical School Hospital) between January 2022 and December 2023. Patients were followed for one year. The outcomes assessed included mortality, treatment modality changes, infection, hospitalization, fluid status, and therapy quality. Results : A total of 70 patients with CKD stage 5D initiated HDF (n = 30) or PD (n = 40) between January 2022 and December 2023. Of these, 57.1% were men, with a mean age of 77.6 ± 5.9 years. Diabetes was the most common underlying condition (37.1%) followed by hypertension (35.7%). During the study period, 18.6% of patients died, and 5.7% switched treatment modalities. Age, sex, underlying diseases, comorbidities and laboratory values were similar between groups, except for differences in initial and 6-month urea levels, initial and 6-month hemoglobin levels, 6-month albumin levels, initial and 12-month phosphorus levels, and initial parathyroid hormone (PTH) levels. No significant differences were found between groups in terms of infection rates, hospitalization, modality changes, or mortality. Logistic regression analysis revealed that PD, infection, and 6-month albumin were independently associated with mortality ((OR = 31.855; [95% CI = 1.643 - 4.440]; p = 0.040); (OR = 2.033; [95% CI = 1.5]; p = 0.026); (OR = 0.363; [95% CI = 0.529]; p = 0.049)). Survival was higher in HDF patients (log-rank = 0.02). Conclusion: In very elderly dialysis patients, infection at 12 months, lower albumin after six months of therapy, and the PD modality were associated with higher mortality.