A prospective crossover trial comparing intermittent intravenous and continuous oral iron supplements in peritoneal dialysis patients.
BACKGROUND
Concomitant iron supplementation is required in the great majority of erythropoietin (Epo)-treated patients with end-stage renal failure. Intravenous (i.v.) iron supplementation has been demonstrated to be superior to oral iron therapy in Epo-treated haemodialysis patients, but comparative data in iron-replete peritoneal dialysis (PD) patients are lacking.


METHODS
A 12-month, prospective, crossover trial comparing oral and i.v. iron supplementation was conducted in all Princess Alexandra Hospital PD patients who were on a stable dose of Epo, had no identifiable cause of impaired haemopoiesis other than uraemia, and had normal iron stores (transferrin saturation >20% and serum ferritin 100-500 mg/l). Patients received daily oral iron supplements (210 mg elemental iron per day) for 4 months followed by intermittent, outpatient i.v. iron infusions (200 mg every 2 months) for 4 months, followed by a further 4 months of oral iron. Haemoglobin levels and body iron stores were measured monthly.


RESULTS
Twenty-eight individuals were entered into the study and 16 patients completed 12 months of follow-up. Using repeated-measures analysis of variance, haemoglobin concentrations increased significantly during the i.v. phase (108+/-3 to 114+/-3 g/l) compared with each of the oral phases (109+/-3 to 108+/-3 g/l and 114+/-3 to 107+/-4 g/l, P<0.05). Similar patterns were seen for both percentage transferrin saturation (23.8+/-2.3 to 30.8+/-3.0%, 24.8+/-2.1 to 23.8+/-2.3%, and 30.8+/-3.0 to 26.8+/-2.1%, respectively, P<0.05) and ferritin (385+/-47 to 544+/-103 mg/l, 317+/-46 to 385+/-47 mg/l, 544+/-103 to 463+/-50 mg/l, respectively, P=0.10). No significant changes in Epo dosages were observed throughout the study. I.v. iron supplementation was associated with a much lower incidence of gastrointestinal disturbances (11 vs 46%, P<0.05), but exceeded the cost of oral iron treatment by 6.5-fold.


CONCLUSIONS
Two-monthly i.v. iron infusions represent a practical alternative to oral iron and can be safely administered to PD patients in an outpatient setting. Compared with daily oral therapy, 2-monthly i.v. iron supplementation in PD patients was better tolerated and resulted in superior haemoglobin levels and body iron stores.
Johnson
D W
DW
Department of Renal Medicine, Princess Alexandra Hospital, Ipswich Road, Woolloongabba, Brisbane, Q 4102, Australia.
Herzig
K A
KA
Gissane
R
R
Campbell
S B
SB
Hawley
C M
CM
Isbel
N M
NM
D000284:Administration, Oral; D018592:Cross-Over Studies; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D016527:Drug Costs; D004921:Erythropoietin / Q000008:administration & dosage / Q000627:therapeutic use; D005260:Female; D005293:Ferritins / Q000097:blood; D006454:Hemoglobins / Q000032:analysis; D006801:Humans; D007275:Injections, Intravenous; D007501:Iron / Q000008:administration & dosage* / Q000009:adverse effects / Q000191:economics / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D010530:Peritoneal Dialysis; D011446:Prospective Studies
D006454:Hemoglobins; D004921:Erythropoietin; D005293:Ferritins; D007501:Iron