[Risk factors for anemia among 6- to 12-month-old children in Brazil]

To estimate the prevalence of anemia and to determine associated risk factors among infants receiving routine health care in public clinics in Brazil.

This cross-sectional study included 2,715 infants between 6 and 12 months old in 12 cities, in all five of the geographic regions of Brazil. Information regarding the child and its feeding habits was obtained from the mother or other caregiver, using a questionnaire. Nutritional status was determined based on height and weight measurements. The hemoglobin concentration was measured using the HemoCue portable hemoglobinometer. Anemia was defined as hemoglobin < 11 g/dL. The infants' eating habits were assessed based on what they were eating around the time of the questionnaire interviews. The association between anemia and the different variables was evaluated through bivariate analysis, followed by multiple logistic regression using a hierarchical selection model.

The prevalence of anemia for the entire group was 65.4%. Multiple regression analysis identified the following risk factors for anemia: living in the Southeastern Region of Brazil (odds ratio (OR) = 1.57, 95% confidence interval (95% CI) = 1.25- 1.99), maternal age < 20 years (OR = 1.58, 95% CI = 1.21-2.07), birthweight < 2,500 g (OR = 2.09, 95% CI = 1.48-2.95), not being breast-fed (OR = 1.28, 95% CI = 1.02-1.61), receiving both breast milk and other foods (OR = 1.40, 95% CI = 1.10-1.78), and male gender (OR = 1.24, 95% CI = 1.06-1.46).

The high proportion of anemic children indicates the need to emphasize, in prenatal and infant health programs, intervention measures for anemia control. Our results could guide these measures, focusing on the groups at greatest risk, such as low birthweight babies and the children of adolescent mothers.