Changes in antioxidant status associated with haemodialysis in chronic kidney disease

Abstract

Oxidative stress has been implicated in the pathogenesis, progression of chronic kidney disease (CKD) and development of cardiovascular complications. Hemodialysis (HD) has also been described to contribute significantly to oxidative stress in CKD patients, though reports are conflicting.

Objective: We evaluated the effects of one session of HD on the antioxidant capacity and lipid peroxidation in CKD patients.

Method: Thirty-six CKD patients requiring HD were recruited into this study. Participants were naïve to HD and each completed a session of three hours using polysulfone membrane dialyzers. Blood samples were collected before and after dialysis. Total antioxidant capacity (TAC) was measured by ferric reducing antioxidant power (FRAP) while malondialdehyde (MDA) was measured using thiobarbituric acid-reactive substance (TBARS). Comparison was made between pre-HD and post-HD values of TAC and MDA respectively, p value of <0.05 was taken as significant.

Result: Mean age and estimated glomerular filtration rate of subjects were 45 ±15 years and 6.3± 4.7mls/1.73m2 respectively. There was significant decrease in the mean TAC from 1232.2 ± 495.6 μmol Trolox equiv/ to 832.4 ±325.7 μmol Trolox equiv/L post-dialysis (p< 0.001) while MDA values were similar before and after HD (11.8 ± 1.8 vs 11.8 ± 2.331)μmol/L (p> 0.05). There was no significant association between changes in antioxidant status following HD with blood flow rate, ultrafiltration volume nor dialyzer per size.

Conclusion: A session of HD in patients with CKD is associated with significant reduction of the total antioxidants capacity; and no effect on MDA levels.

Funding: No external funding received

Keywords: oxidative stress, antioxidants capacity, hemodialysis, chronic kidney disease