Objectives: The etiology of the 10-fold increase in anemia and iron deficiency prevalence among Alaska Native individuals from the culturally traditional southwestern/northern Alaska regions remains unknown. The present study sought to determine anemia prevalence among people enrolled in the Alaska Women, Infant, and Children (WIC) program and reconcile results with etiological hypotheses, particularly nutritional iron deficiency and Helicobacter pylori infection.
Patients and Methods: An analysis was conducted of 50,964 children 6 to 59 months of age and 30,154 pregnant or postpartum women enrolled in WIC during 1999 to 2006. Based on 3 regional groupings of residence and Alaska Native status, 6 strata were defined.
Results: Southwestern/northern Alaska Native children—who are known to have high nutritional iron intake based on subsistence diets—had the highest anemia prevalence (35%). However, southwestern/northern residence increased anemia risk similarly for Alaska Native (relative risk 1.6) and non-Native (relative risk 1.5) children. Anemia prevalence was highest among the youngest children and declined with increasing age at approximately the same rate regardless of race or residence. Alaska Native pregnant or postpartum women from all of the regions had higher anemia prevalences than non-Native women; southwestern/northern residence conferred additional risk to Alaska Native women.
Conclusions: A region-specific environmental factor is supported by the increased risk seen among all of the children residing in the southwestern/northern regions. However, the observed patterns make nutritional iron deficiency or H pylori infection unlikely as the sole or major etiologies of the high anemia prevalences observed in some groups.