Comparison between Type A and Type B Early Adiposity Rebound in predicting overweight and obesity in children: a longitudinal study.

Early adiposity rebound (EAR) predicts pediatric overweight/obesity, but current approaches do not consider both the starting point of EAR and the BMI trajectory. We compared the clinical characteristics at birth, age 3-5 and 6-8years of children, according to the presence and absence of EAR and according to type of EAR (type A/type B-EAR), and we assessed the children's odds of being classified with overweight/obesity at age 6-8, according to the type of EAR as defined at age 3-5. 1055 children were recruited and examined at 3-5yrs as part of a two-wave observational study. Antenatal and post-natal information were collected through interviews with parents, and weight and height from the health records. Type A and type B-EAR were defined in wave 1 according to the situation relative to the position of the BMI nadir and the variation of BMI z-score between the starting point of the adiposity rebound and the last point on the curve. At 6-8yrs (wave 2), 867 children were followed-up. 426 children demonstrated EAR (40.4%). Among them, 172 had Type A-EAR and exhibited higher rates of parental obesity (p<0.05) and greater birthweight compared to other children (p<0.001). Odds for overweight/obesity at 6-8yrs, when adjusting for antenatal and post-natal factors, was 21.35 [10.94-41.66] in Type A-EAR children, and not significant in Type B-EAR children (OR= 1.76 [0.84-3.68]) compared to children without EAR. Classification of EAR in two subtypes provides physicians with a reliable approach to identify children at risk for overweight/obesity before the age of 5yrs.