Effluent free radicals are associated with residual renal function and predict technique failure in peritoneal dialysis patients.
OBJECTIVE
Residual renal function (RRF) is associated with low oxidative stress in peritoneal dialysis (PD). In the present study, we investigated the relationship between the impact of oxidative stress on RRF and patient outcomes during PD.


METHODS
Levels of free radicals (FRs) in effluent from the overnight dwell in 45 outpatients were determined by electron spin resonance spectrometry. The FR levels, clinical parameters, and the level of 8-hydroxy-2'-deoxyguanosine were evaluated at study start. The effects of effluent FR level on technique and patient survival were analyzed in a prospective cohort followed for 24 months.


RESULTS
Levels of effluent FRs showed significant negative correlations with daily urine volume and residual renal Kt/V, and positive correlations with plasma β(2)-microglobulin and effluent 8-hydroxy-2'-deoxyguanosine. A highly significant difference in technique survival (p < 0.05), but not patient survival, was observed for patients grouped by effluent FR quartile. The effluent FR level was independently associated with technique failure after adjusting for patient age, history of cardiovascular disease, and presence of diabetes mellitus (p < 0.001). The level of effluent FRs was associated with death-censored technique failure in both univariate (p < 0.001) and multivariate (p < 0.01) hazard models. Compared with patients remaining on PD, those withdrawn from the modality had significantly higher levels of effluent FRs (p < 0.005).


CONCLUSIONS
Elevated effluent FRs are associated with RRF and technique failure in stable PD patients. These findings highlight the importance of oxidative stress as an unfavorable prognostic factor in PD and emphasize that steps should be taken to minimize oxidative stress in these patients.
Department of Medicine and Clinical Science, Center for Chronic Kidney Disease and Peritoneal Dialysis, Okayama University Graduate School of Medicine, Okayama, Japan.
Hiroshi
H
Morinaga
Hitoshi
H
Sugiyama
Tatsuyuki
T
Inoue
Keiichi
K
Takiue
Yoko
Y
Kikumoto
Masashi
M
Kitagawa
Shigeru
S
Akagi
Kazushi
K
Nakao
Yohei
Y
Maeshima
Ikuko
I
Miyazaki
Masato
M
Asanuma
Makoto
M
Hiramatsu
Hirofumi
H
Makino
D000368:Aged; D000369:Aged, 80 and over; D003839:Deoxyadenosines / Q000032:analysis; D004578:Electron Spin Resonance Spectroscopy; D005260:Female; D005609:Free Radicals / Q000378:metabolism*; D006801:Humans; D007668:Kidney / Q000378:metabolism*; D007676:Kidney Failure, Chronic / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D018384:Oxidative Stress; D010530:Peritoneal Dialysis / Q000379:methods* / Q000401:mortality; D010537:Peritoneum / Q000378:metabolism*; D011446:Prospective Studies; D016019:Survival Analysis
C436623:8-hydroxy-2'-deoxyadenosine; D003839:Deoxyadenosines; D005609:Free Radicals