The impact of iron deficiency on prognosis in stroke and non-stroke populations: A retrospective cohort study.

Background And Aims: Iron deficiency (ID) leads to a significant global health burden, but research on the impact of ID on the prognosis of stroke patients is rare. We aim to investigate the impact of ID on the all-cause mortality of both the stroke and non-stroke individuals.

Methods And Results: This retrospective cohort study used data from the National Health and Nutrition Examination Survey (NHANES) conducted from 1999 to 2002. The follow-up period for the participants extended until December 31, 2019. Overall, 7239 participants were enrolled, out of which 200 had a history of stroke. There was no difference in the prevalence of ID (ferritin <100 ng/mL or serum ferritin concentration 100-299 ng/mL with transferrin saturation (TSAT) < 20 %) between stroke and non-stroke individuals (68 % vs 65 %, P = 0.5) even after propensity score matching (68 % vs 63 %, P = 0.5). In stroke survivors, ID was found to be associated with a higher risk of all-cause mortality over a 5-year period (HR: 4.16, 95 % CI: 1.54-11.3, P = 0.005). Additionally, there was no link between ID and all-cause mortality in individuals without stroke. Moreover, we did not observe a significant association between dietary iron, total folate, and ID in stroke patients.

Conclusion: Stroke survivors with low serum ferritin levels have an increased risk of 5-year all-cause mortality. Health care providers should consider screening for ID among individuals with a history of stroke. Future clinical trials examining the effects of iron therapy on patients with stroke and coexisting ID are warranted.