Researchers studied some 2600 initially dementia-free older adults, 15% of whom had anemia at baseline. During 11 years’ follow-up, 18% of participants developed dementia. After adjustment for potential confounders such as age, sex, APOE genotype, comorbid conditions, and literacy, participants with anemia had a significant, 49% increase in risk for dementia relative to those without anemia.
The researchers say their findings are consistent with those from previous studies, and they suggest several possible mechanisms underlying the association. For example, the brain hypoxia that occurs with anemia might contribute to dementia risk, or anemia could be a marker of overall poor health. They call for additional research to determine whether hemoglobin levels should be the focus of prevention strategies.