Body composition of preschool children and relation to birth weight

Objective: to evaluate the relationship between body composition of preschool children suffering from excess weight and birth weight (BW). Methods: probabilistic sample, by conglomerates, with 17 daycare centers (of a total of 59) composing a final sample of 479 children. We used Z-score of Body Mass Index (zBMI) ≥ +1 and ≥ +2, respectively, to identify preschool children with risk of overweight and excess weight (overweight or obesity). The arm muscle area (AMA) and the arm fat area (AFA) were estimated from measurements of arm circumference, triceps skin fold thickness. Results: the prevalence of risk of overweight was 22.9% (n=110) and excess weight was 9.3% (n=44). The risk of overweight and excess weight in children did not show correlation between BW and AFA, but it did with adjusted arm muscle area (AMAa) (rp= 0.21; p= 0.0107). The analysis of the group with excess weight alone also showed a positive correlation between BW and AMAa (rp= 0.42; p= 0.0047). Conclusion: among overweight children, lower BW is associated with a lower arm muscle area in early preschool age, regardless of the fat arm area presented by them. .

Objetivo: avaliar a relação entre a composição corporal de pré-escolares portadores de excesso de peso e o seu peso ao nascimento (PN). Métodos: amostra probabilística, por conglomerados, com 17 creches (de um total de 59), composta por 479 crianças. Para identificar os pré-escolares portadores de risco de sobrepeso e de excesso de peso (sobrepeso ou obesidade), utilizou-se o escore Z de índice de massa corpórea (zIMC) ≥ +1 e ≥ +2, respectivamente. A área muscular do braço corrigida (AMB) e a área gorda do braço (AGB) foram estimadas a partir das medidas de circunferência do braço e da dobra cutânea tricipital. Resultados: a prevalência de risco de sobrepeso foi de 22.9% (n= 110) e de excesso de peso de 9.3% (n= 44). Juntas, as crianças com risco de sobrepeso e excesso de peso não mostraram correlação entre o PN e a área gorda do braço, mas, sim, com a área muscular do braço corrigida (AMBc) (rp= 0.21; p= 0.0107). A análise só do grupo com excesso de peso também evidenciou correlação positiva entre PN e AMBc (rp= 0.42; p= 0.0047). Conclusão: nas crianças com excesso de peso, um menor PN está associado a uma menor área muscular do braço no início da idade pré-escolar, independentemente da área gorda do braço que elas apresentem. .

Ratio of weight to height gain: a useful tool for identifying children at risk of becoming overweight or obese at preschool age

PURPOSE: To analyze the usefulness of the weight gain/height gain ratio from birth to two and three years of age as a predictive risk indicator of excess weight at preschool age. METHODS: The weight and height/length of 409 preschool children at daycare centers were measured according to internationally recommended rules. The weight values and body mass indices of the children were transformed into a z-score per the standard method described by the World Health Organization. The Pearson correlation coefficients (rP) and the linear regressions between the anthropometric parameters and the body mass index z-scores of preschool children were statistically analyzed (alpha = 0.05). RESULTS: The mean age of the study population was 3.2 years (± 0.3 years). The prevalence of excess weight was 28.8 percent, and the prevalence of overweight and obesity was 8.8 percent. The correlation coefficients between the body mass index z-scores of the preschool children and the birth weights or body mass indices at birth were low (0.09 and 0.10, respectively). There was a high correlation coefficient (rP = 0.79) between the mean monthly gain of weight and the body mass index z-score of preschool children. A higher coefficient (rP = 0.93) was observed between the ratio of the mean weight gain per height gain (g/cm) and the preschool children body mass index z-score. The coefficients and their differences were statistically significant. CONCLUSION: Regardless of weight or length at birth, the mean ratio between the weight gain per g/cm of height growth from birth presented a strong correlation with the body mass index of preschool children. These results suggest that this ratio may be a good indicator of the risk of excess weight and obesity in preschool-aged children.