Platelet reactivity and platelet count in women with iron deficiency treated with intravenous iron

Background: Iron deficiency anemia (IDA) and heavy menstrual bleeding are prevalent, interrelated issues impacting over 300 million premenopausal women worldwide. IDA is generally associated with increased platelet counts; however, the effects of IDA and its correction on platelet function in premenopausal women remain unknown. Objectives: We sought to determine how IDA and intravenous iron affect platelet count and platelet function in premenopausal women. Methods: Hematologic indices were assessed in a multicenter, retrospective cohort of 231 women repleted with intravenous iron. Pre- and postinfusion blood samples were then obtained from a prospective cohort of 13 women to analyze the effect of intravenous iron on hematologic parameters as well as platelet function with flow cytometry and platelet aggregation assays under physiologic shear. Results: Following iron replacement, anemia improved, and mean platelet counts decreased by 26.5 and 16.0 K/mm³ in the retrospective and prospective cohorts, respectively. Replacement reduced baseline platelet surface P-selectin levels while enhancing platelet secretory responses to agonists, including collagen-related peptide and ADP. Platelet adhesion and aggregation on collagen under physiologic shear also significantly increased following repletion. Conclusion: We find that intravenous iron improves anemia while restoring platelet counts and platelet secretory responses in premenopausal women with iron deficiency. Our results suggest that iron deficiency as well as iron replacement can have a range of effects on platelet production and function. Consequently, platelet reactivity profiles should be further examined in women and other groups with IDA where replacement offers a promising means to improve anemia as well as quality of life.