Birth weight, rapid weight gain in infancy and markers of overweight and obesity in childhood.

objectiveTo evaluate the relationship between birth weight and rapid weight gain in infancy and markers of overweight/obesity in childhood, using different cutoff values for rapid weight gain. SUBJECTS/

methodsCross-sectional study involving 98 5-year old pre-school Brazilian children. Rapid weight gain was considered as weight gain in standard deviation score (SDS) above +0.67, +1 and +2 in relation to birth weight, at any time during the first 2 years of life. The nutritional status of the children was determined by anthropometry and electrical bioimpedance. Multiple linear regression analysis was used, considering fat mass percentage, body mass index (BMI), waist and neck circumferences as outcomes.

resultsBirth weight, rapid weight gain (assessed by different cutoff values) and maternal obesity were positively associated with increased fat mass percentage, BMI, waist and neck circumferences. Different cutoff values of rapid weight gain did not change the positive associations between rapid weight gain and fat mass percentage (>+0.67 SDS, P=0.007; >+1 SDS, P=0.007; >+2 SDS, P=0.01), BMI (>+0.67 SDS, P=0.002; >+1 SDS, P=0.007; >+2 SDS, P<0.001), waist circumference (>+0.67 SDS, P=0.002; >+1 SDS, P=0.002; >+2 SDS, P<0.001) and neck circumference (>+0.67 SDS, P=0.01; >+1 SDS, P=0.03; >+2 SDS, P<0.001).

conclusionsThe use of different cutoff values for the definition of rapid weight gain did not interfere in the associations between birth weight and rapid weight gain with fat mass percentage, BMI, waist and neck circumferences. Children with the highest birth weight, those who undergo rapid weight gain in infancy and whose mothers were obese, seemed to be more at risk for overweight/obesity.