Long-Term Intravenous Iron Therapy and Morbidity in Hemodialysis Patients

Abstract

Objective: The aim of this study was to describe long-term intravenous iron therapy-associated morbidity in hemodialysis patients from a single Hemodialysis Center. Material and methods: We conducted an observational retrospective cohort study from 01 January to 31 December 2015. Two hundred and twenty prevalent patients on maintenance hemodialysis therapy for at least 12 months (mean age 53±13 years, 56% males, median hemodialysis vintage 5 (1-26) years) were included. Diabetic nephropathy as primary kidney disease, pregnancy and incomplete data records regarding study aims were exclusion criteria. We compared the frequency, duration and causes of hospitalizations in iron sucrose-treated versus gender and age-matched iron non-treated patients. Differences between groups were assessed using Chi-square and Kruskal-Wallis H tests. A p value μ0.05 was considered statistically significant. Results: From the entire cohort, 68% were iron-treated. One in five patients were treated with higher doses (400 mg monthly), and lower doses were used (100-200 mg monthly) in 80% of patients. There were no differences regarding the rates of admission between the two groups (56/100 patient-years in the iron sucrose-treated vs. 50/100 patient-years in the iron-untreated group, p=0.1). Still, the hospitalization rate significantly increased with the administered iron dose (0.4 vs. 0.7 vs. 0.8/100 patient-years for 100 mg vs. 200 mg vs. 400 mg monthly, respectively, p=0.006). Hospitalization rates due to infectious and cardiovascular diseases were similar for both groups (12/100 patient-years vs. 5.7/100 patient-years, p=0.3 and 11.3/100 patient-years vs. 4.3/100 patient-years, p=0.2, respectively). Conclusion: Higher doses of intravenous iron sucrose appear to be associated with an elevated risk of hospitalization. Nonetheless, long-term intravenous iron therapy seems to have a limited influence in terms of specific cause of morbidity in non-diabetic hemodialysis patients.

TABLE 1.

Characteristics of patients according to the presence of iron therapy

TABLE 2.

The requirements of hospital admission during the study period

FIGURE 1.

Percentages of patients by number of hospital admissions. Fe: iron untreated, Fe+: iron treated

FIGURE 2.

Main causes of hospital admission. Fe: iron untreated, Fe+: iron treated, CV: cardiovascular, VA: vascular access

FIGURE 3.

Percentage of admitted patients based on the iron dose

FIGURE 4.

Hospitalization rate based on iron dose