Changes in serum markers of oxidative stress with varying periods of haemodialysis

Background and Aims: Oxidative stress possibly helps promote the progression and complications of chronic renal failure (CRF). Haemodialysis (HD) may aggravate oxidative stress. This controlled, cross-sectional clinical study with blind outcome assessment evaluated the effect of prolonged HD treatment on oxidative stress. Methods and Results: Seventy patients (M/F = 33/37) with CRF and who were on HD were divided into six groups with differing treatment periods of HD; from 3 to 12 months to 85-120 months. Twelve healthy subjects acted as controls. The serum levels of thiobarbituric acid reactive substances (TBARS), total sulfhydryl (SH) groups and protein carbonyls (PCs) were determined. Compared with controls, PCs were increased in patients, and this positively correlated with the duration of HD. Treatment for more than 24 months caused the most striking increases in PCs, with relevant differences as compared to those on HD for a maximum of 12 months. Increasing periods of HD were associated with increases in TBARS and similar decreases in SH as compared with controls; the differences between the SH levels of those on HD for more than 84 months and those on HD for up to 24 months were significant. Conclusion: Our results indicate that HD continued for more than 2 years aggravates the latter. Decreased potential for oxygen-radical-scavenger activity becomes pronounced after 7 years of HD treatment.