The effect of serum albumin level on iron-induced oxidative stress in chronic renal failure patients.

BACKGROUND

Intravenous iron (IVIR) administration is widely used to treat anemia in chronic renal failure (CRF) patients and causes oxidative stress. Despite the fact that proteins are extremely susceptible to oxidative stress, there have been no studies investigating the relationship between the severity of iron-induced acute oxidative stress and serum albumin. Therefore, we wanted to investigate the relation between the severity of iron-induced acute oxidative stress and serum albumin level in CRF patients.

METHODS

A total of 68 patients (22 on hemodialysis, 24 on continuous ambulatory peritoneal dialysis and 22 predialytic CRF) with absolute iron deficiency were included to the study. Patients with acute inflammatory status, serum ferritin level > or = 100 ng/mL, transferrin saturation > or = 20%, hemoglobin level > or = 12 g/dL or serum C-reactive protein (CRP) level > or = 10 mg/dL were excluded. Serum direct 8-isoprostoglandin F2 alpha (IsoPG-F2 alpha) level was used as an oxidative stress marker. After baseline sampling, 100 mg ferric sucrose was infused within 30 minutes. Blood samples were drawn to assess changes in oxidative stress marker at the end of the IVIR infusion and at 240 minutes. Patients with serum albumin level <4 g/dL were defined as hypoalbuminemic and > or = 4 g/dL as normoalbuminemic.

RESULTS

There were 34 hypoalbuminemic and 34 normoalbuminemic patients. Serum IsoPG-F2 alpha level increased in all patients after the administration of IVIR. The severity of iron-induced acute oxidative stress was more prominent in patients with a low serum albumin level. Serum albumin level, presence of diabetes mellitus (DM) and hemoglobin level were found as significant predictors of time-dependent changes in serum IsoPG-F2 alpha level. When the analyses were repeated in nondiabetic patients, serum albumin level was similarly found to be a significant predictor of time-dependent changes in serum IsoPG-F2 alpha level.

CONCLUSION

This study demonstrated a negative interaction between iron-induced acute oxidative stress and serum albumin level in CRF patients. Because CRF patients with low serum albumin level are at greater risk for iron-induced acute oxidative stress, new strategies are necessary in this population.