Quality of life of patients with pre-dialysis chronic kidney disease, its relationship with oxidant stress and uromodulin excretion

Background. The purpose of this study was to assess the quality of life (QoL) in patients with pre-dialysis chronic kidney disease (CKD), to reveal the factors affecting the QoL in this category of patients and to investigate the effect of antioxidant therapy on the QoL of patients with CKD stages 1–5. Mate­rials and methods. Patients with CKD (n = 61), whose average age was 44.51 ± 11.90 years, were included in the study. Twenty (32.79 %) men and 41 (67.21 %) women were divided into two groups representative in terms of age and gender composition: group 1 (n = 31) — patients with CKD who took glutathione 100 mg 2 times a day with meals for 3 months, group 2 (n = 30) — those with CKD who took ubiquinone 100 mg once daily with meals for 3 months. The QoL was assessed using the SF-36 questionnaire. Patient adherence to treatment was assessed with the Morisky-Green test. To assess the kidney function of patients, the level of urinary uromodulin excretion (uUMOD), urine albumin-to-creatinine ratio (ACR) were determined. The impact of antioxidant therapy on the QoL of these patients was evaluated and the factors affecting QoL were determined. Results. In the structure of CKD, urolithiasis was most common — 22 (36.1 %) patients, 5 (8.2 %) people had chronic pyelonephritis, 18 (29.5 %) — diabetic nephropathy, 4 (6.6 %) — polycystic kidney disease, 6 (9.8 %) — gouty nephropathy, 1 (1.6 %) — chronic glomerulonephritis and 5 (8.2 %) patients presented with hypertensive nephropathy. The duration of CKD in the first group was 5.42 ± 3.88 (1; 15) years, in the second one — 5.57 ± 3.79 (1; 16) years, no significant difference was found between the groups in terms of age and gender (U = 463m, p = 0.9827). In all patients, the indicators at the beginning were lower than those by the end of the study. The lowest indicator in the first group is general health, in the second — vitality. The psychological component of health (PsCH) was lower than the physical component of health (PhCH) in both groups. A significant positive relationship (p < 0.001) was observed, which was most pronounced for glomerular filtration rate (GFR), ACR, systolic blood pressure, hemoglobin. At the end of the study, 12 (19.67 %) patients had 4 points on the Morisky-Green test, which meant high adherence to therapy. There was a reliable strong positive relationship between the QoL and GFR, ACR, ­uUMOD. At the beginning of treatment, a significant average positive relationship was found between the QoL (PhCH) and uUMOD: r (59) = 0.372, p = 0.003; between the QoL (PhCH) and GFR, there is a significant positive relationship: r (59) = 0.707, p < 0.001. There is a very insignificant positive relationship between the QoL (PsCH) and patients’ adherence to treatment, r (59) = 0.0882, p = 0.499. Conclusions. Antioxidant therapy with glutathione and ubiquinone significantly improves the QoL of patients with CKD. Considering the safety and effectiveness of antioxidant therapy, we suggest including antioxidant therapy in treatment protocols for patients with CKD. Further research is recommended to determine a standard protocol.