Iron deficiency anemia is associated with abnormal cerebral metabolic rate, blood brain barrier permeability and cognitive function.

Iron deficiency is the predominant cause of anemia in adults, typically occurring in women with heavy menses, endometriosis or fibroids. We study cerebral metabolic rate of oxygen (CMRO2), blood brain barrier (BBB) permeability to water, and neurocognitive function in 34 women with iron deficiency anemia (IDA). We observed striking deficits in verbal and spatial memory, perceptual reasoning, and crystalized intelligence that were strongly correlated with hemoglobin level. CMRO2 was lower than predicted by anemia alone, correlated to BBB permeability to water, and associated with poorer neurocognitive performance, suggesting decreased brain capillary surface area for oxygen and water diffusion.