Obesity risk in 10-year-old children, based on attributes observed at 4 years of age, provides evidence on how to target interventions to lower obesity rates in mid-childhood

Introduction: although in Chile 75 % of obese preschool children participate in a primary health intervention, obesity rates have increased. Objective: to determine the risk of children being obese in 5 grade (10 yrs), according to biological and social attributes observed when they attended prekindergarten (PK) at 4 yrs, to determine which preschoolers should be prioritized for targeting. Method: a retrospective cohort study including 55,623 participants. The variables collected when children attended PK were age, sex, weight, height, maternal educational level and employment status, the child´s relationship with persons living at home, person in charge of the child after school, and number of household members, plus weight, height, and age in 5 grade. To determine the risk of being obese in 5 grade we did two logistic regression models—the first one included all PK children and the above variables, while the second model considered additionally the presence of obesity in PK. The rest of the variables were the same. Results: the risk of children being obese in 5 grade (10 yrs) was 1.43 times higher if their mothers had ≤ 8 yrs of schooling, 1.13 times higher if they lived with a grandparent, and slightly higher if their mothers had an occupation (1.04 times). Boys had a significantly higher risk (1.74 times). Obesity at 4 yrs constituted the highest obesity risk later on (5.3 times). Conclusions: targeting obese 4-year-old boys who participate in a primary health intervention, whose mothers have low education and who live with a grandparent, may lower obesity rates in mid-childhood.