Overweight among children under five years of age in municipalities of the semiarid region.

Objective: To measure the prevalence and to identify factors associated with overweight among children under five years old living in two municipalities in the semiarid region of Piauí, Brazil.

Methods: Previously trained interviewers visited all of the households in these municipalities and applied standard questionnaires to the mothers of the children. The questionnaires sought information on: the demographic characteristics of the mother and children, the family's socioeconomic status, care received during pregnancy and at childbirth, breastfeeding and dietary patterns. Overweight (>+ 1 standard deviation from the median to the reference population) was calculated transforming body mass index into Z scores, according to the standard by the World Health Organization (WHO). The statistical analysis was performed using Poisson regression with robust adjustment of variance.

Results: The prevalence of overweight among the 1,640 children evaluated was of 30.2% (95%CI 27.9 - 32.4). This prevalence varied from 13.2% among children born weighing less than 2,500 g to 43.4% among those aged 12 to 23 months. Adjusted analysis showed that the prevalence ratios (PR) for overweight in children aged 48 to 59 months was 1.42 (1.07 - 1.86) for overweight compared to those aged between 0 and 11 months, whereas children pertaining to the highest quartile income showed PR = 1.44 (1.17 - 1.76) when compared to the lowest quartile. Finally, children born with weight ≥ 3500 g, the PR for overweight was 2.32 (1.33 - 4.05) in relation to those born with low weight (< 2500 g).

Conclusion: Even in the semiarid region, the prevalence of overweight is high, and the need for early intervention to change this situation seems to be evident.