Increased iron requirement in hemodialysis patients on antiplatelet agents or warfarin.
OBJECTIVE
Many hemodialysis patients receive antiplatelet therapy or warfarin; however, little is known about the effect of this on iron requirements. Given the association of antiplatelet therapy with bleeding we hypothesized that there should be a greater need for iron in such patients, which we tested in this study.


METHODS
Retrospective 1-year cohort study of 205 chronic hemodialysis patients. The primary outcome variable was total iron dose, which was analyzed according to antiplatelet/warfarin use. Data were also collected on potential confounders, allowing for both unadjusted and adjusted (multiple regression) analysis.


RESULTS
97/205 patients received antiplatelet/warfarin therapy. This group was older, with a higher incidence of macrovascular disease and diabetes and a higher median C-reactive protein (6.0 vs. 3.75 mg/l). Overall, median iron requirement was 1,300 mg/year. In a multiple regression analysis, antiplatelet/warfarin use was associated with an additional iron requirement of 703 mg (95% confidence interval 188-1,220 mg), with the strongest effect observed in patients with normal inflammatory markers.


CONCLUSIONS
We found a high requirement for iron in patients receiving antiplatelet agents/warfarin. We argue that the most likely mechanism for this association is chronic, low-grade blood loss, although further study is required before causality can be established.
Flint
Shaun
S
Department of Nephrology, Royal Melbourne Hospital, Vic., Australia. shaun@youngdoc.net
Taylor
Emma
E
Beavis
Jennifer
J
Becker
Gavin J
GJ
Pedagogos
Eugenie
E
D000367:Age Factors; D000368:Aged; D018798:Anemia, Iron-Deficiency / Q000097:blood / Q000188:drug therapy / Q000209:etiology*; D002097:C-Reactive Protein / Q000032:analysis; D015897:Comorbidity; D003928:Diabetic Nephropathies / Q000097:blood / Q000453:epidemiology / Q000628:therapy; D005260:Female; D005290:Ferric Compounds / Q000008:administration & dosage / Q000627:therapeutic use; D005293:Ferritins / Q000097:blood; D006470:Hemorrhage / Q000097:blood / Q000139:chemically induced*; D006801:Humans; D007249:Inflammation / Q000453:epidemiology; D007501:Iron / Q000097:blood; D000090463:Iron Deficiencies; D007676:Kidney Failure, Chronic / Q000097:blood* / Q000150:complications / Q000628:therapy; D008297:Male; D008875:Middle Aged; D009751:Nutritional Requirements; D010975:Platelet Aggregation Inhibitors / Q000009:adverse effects* / Q000627:therapeutic use; D006435:Renal Dialysis; D012189:Retrospective Studies; D019851:Thrombophilia / Q000188:drug therapy / Q000453:epidemiology; D014168:Transferrin / Q000032:analysis; D014652:Vascular Diseases / Q000453:epidemiology; D014859:Warfarin / Q000009:adverse effects* / Q000627:therapeutic use
D005290:Ferric Compounds; D010975:Platelet Aggregation Inhibitors; D014168:Transferrin; D014859:Warfarin; D002097:C-Reactive Protein; D005293:Ferritins; D007501:Iron; C013276:teferrol