Biological interactions of aging and anemia: a focus on cytokines.

Anemia is one of the characteristics of the frailty phenotype and is often observed in elderly patients. Although anemia in people of advancing age can often be attributed to underlying etiologies such as iron deficiency or chronic disease, some cases do not have any identifiable cause. Therefore, it has been suggested that the aging process itself might be an intrinsic factor in the development of anemia, possibly through the age-related dysregulation of certain proinflammatory cytokines such as interleukin-6 (IL-6). Although the mechanism underlying the association between increased IL-6 and anemia has not been fully elucidated, it has been suggested that, like with other cytokines, it involves direct inhibition of erythropoietin production or interaction with the erythropoietin receptor.