Impact of Transferrin Saturation on All-Cause Mortality in Patients on Maintenance Hemodialysis

Transferrin saturation (TSAT) is an index that represents the iron-binding capacity of transferrin, which is the main transport protein for iron, and is widely used to evaluate iron status.

To evaluate the prognostic importance of TSAT in Japanese patients on maintenance hemodialysis (MHD).

A total of 398 patients on MHD were recruited and divided into 3 groups on the basis of their baseline TSAT levels (<20, 20-40, and >40%).

There was no difference in the proportion of patients on erythropoiesis-stimulating agents or iron supplements between the 3 groups. During a mean follow-up period of 52.2 ± 1 6.3 months, 130 patients died of cardiovascular causes (n = 63, 15.8%) or infection (n = 47, 11.8%). Compared with the reference group (TSAT 20-40%), patients with a TSAT <20% had a significantly higher all-cause mortality rate (6.44 vs. 9.55 events per 100 patient-years, p = 0.0452). Kaplan-Meier analysis showed that all-cause mortality rate was significantly higher in patients with TSAT <20% than in the other 2 groups (p = 0.0353).

Low TSAT was a significant independent risk factor for all-cause mortality in a cohort of Japanese patients on MHD. The findings of this study suggest that the adverse clinical outcomes in patients with low TSAT can be partly attributed to infection-related iron deficiency.