Predictors of improvement in hemoglobin among toddlers

Nutrition Research Newsletter, June, 2005

Nutrition supplementation programs, like the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC), are generally directed to members of the population who are most at risk for some undesirable outcomes, on the premise that those who are most at risk of this undesirable outcome are most likely to need supplementation, and therefore to improve in response to receiving it. This study was designed to determine which subgroup of WIC participants improves while taking part in the WIC program. Therefore, some researchers from Cornell University identified which characteristics were associated with an improvement in anemia status in children over a year's time. Reduction in anemia was chosen as the outcome because anemia is common, affecting 18.4% of children under two years of age in the United States, and children who are anemic at this age continue to have poorer cognition and school achievement, as well as more behavioral problems later in childhood than nonanemic children.

An observational study with data from 9930 children who were enrolled in the Massachusetts WIC program, was conducted. Hemoglobin values at both one and two years of age were used. A hemoglobin concentration of less than 110 g/L was used as a cut-off for anemia. Other data that was used in the study included sociodemographic variables and indicators of growth (length-for-age, weight-for-age, and weight-for-length z scores and percentiles).

Baseline and change in hemoglobin values differed significantly by racial or ethnic group. Hemoglobin concentrations increased from age one to two years in white and Hispanic babies who had been breastfed, and for Hispanics the change in hemoglobin values was greater among females. The mother's education and the infant's weight at baseline were significantly and positively associated with hemoglobin at one year of age. Infant weight at baseline was significantly associated with a decrease in hemoglobin from age one to two years.

The main finding was that a longer duration of breastfeeding predicts improvement in hemoglobin during the second year of life while enrolled in the WIC program. It is significant that most of the children in the sample had been receiving a nutritional intervention of iron-fortified cereal and/or iron-fortified formula for up to one year before the start of the analysis, because they had been enrolled in WIC at birth, or within six months after birth. Therefore, these findings are particularly strong, and underestimate the benefits to one year old children who enter the WIC program for the first time. If current efforts to increase the duration of breastfeeding among WIC participants are successful, the importance of WIC in improving hemoglobin concentration among young children will also increase.

Kristine Altucher, Kathleen Rasmussen, Elizabeth Barden and Jean-Pierre Habicht. Predictors of Improvement in Hemoglobin Concentration among Toddlers Enrolled in the Massachusetts WIC Program, JADA; 105:709-715 (May, 2005). [Correspondence: Kathleen Rasmussen, ScD, RD, Division of Nutritional Sciences, 111 Savage Hall, Cornell University, Ithaca, NY 14853. E-mail: kmr5@cornell.edu]