Persistence and emergence of anemia in children during participation in the special supplemental nutrition program for women, infants, and children

Context: The prevalence of iron-deficiency anemia in children has decreased owing to the provision of ironcontaining infant formula and cereal and food vouchers to children enrolled in the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC). Objective: To determine the prevalence of anemia and changes in anemia status in children receiving WIC supplementation. Design: Retrospective cross-sectional and longitudinal analysis of information on WIC participants. Two definitions of anemia were condisered separately: Anemial and Anemia2, the latter using a more stringent definition of anemia to avoid misclassification. Participants: Consecutive cohort of 7053 infants and children aged 6 to 59 months. Main Outcome Measures: Prevalence of anemia by age and race or ethnicity and relationship between anemia and sex, birth weight, and weight-for-height z score. Results: Infants aged 6 to 8 months were 3.3 times more likely to be anemic than children aged 36 to 59 months. There was no association between anemia and race, birth weight, sex, of weight-for-height z score. Anemia rates were approximately halved in the more stringently defined Anemia2 group. Among children seen for at least 3 visits (n = 2926), 8.5% developed anemia and 19.1% of initially anemic children remained anemic; an additional 6.6% developed anemia at a third visit after having had 2 normal hemoglobin measurements. Conclusions: Anemia was common in WIC participants, with infants at highest risk. The diagnosis of anemia in black children depends on the cutoff value used. Despite ongoing receipt of WIC benefits, many children develop anemia or remain anemic. Implementation of mandatory follow-up of all anemic infants by WIC or health care providers may be warranted.