Keywords
Anemia
Iron deficiency
Iron metabolism
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Abstract
Objective: To analyze the mechanisms involved in iron dysregulation associated with long COVID through an integrative review, in order to broaden the understanding of its clinical and pathophysiological outcomes. Methods: This review was conducted between January and October 2025, aiming to identify, synthesize, and evaluate evidence regarding anemia phenotypes related to long COVID, their classifications, and clinical correlations. The search was performed in the MEDLINE/PubMed, SciELO, Latindex, and LILACS/BVS databases. Results: Analysis of the identified studies revealed hematological disorders, predominantly inflammation-related anemia, characterized by hyperhepcidinemia, functional iron restriction, and reduced erythropoiesis. Structural and biochemical red blood cell alterations were also described, including membrane modifications, increased carboxyhemoglobin, and signs compatible with subclinical hemolysis. These abnormalities were associated with decreased exercise capacity, fatigue, and slow recovery. Men and individuals with severe acute COVID-19 were more likely to maintain hematological alterations, highlighting the role of inflammation and iron–heme dysfunction in the condition’s pathophysiology. Final considerations: Long COVID involves anemia and dysregulation of iron metabolism, reinforcing the importance of continuous laboratory monitoring and evaluation to guide timely interventions.
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