Predicting Early Emergence of Childhood Obesity in Underserved Preschoolers

Objective
To determine the magnitude of risk of factors that contribute to the emergence of childhood obesity among low-income minority children.

Study design
We conducted a prospective cohort analysis of parent−child pairs with children aged 3-5 years who were nonobese (n = 605 pairs) who participated in a 3-year randomized controlled trial of a healthy lifestyle behavioral intervention. After baseline, height and weight were measured 5 times over 3 years to calculate body mass index (BMI) percentiles and classify children as normal, overweight, or obese. Multivariable logistic regression was used to estimate the odds of obesity after 36 months. Predictors included age, sex, birth weight, gestational age, months of breastfeeding, ethnicity, baseline child BMI, energy intake, physical activity, food security, parent baseline BMI, and parental depression.

Results
Among this predominantly low-income minority population, 66% (398/605) of children were normal weight at baseline and 34% (n = 207/605) were overweight. Among normal weight children at baseline, 24% (85/359) were obese after 36 months; among overweight children at baseline, 55% (n = 103/186) were obese after 36 months. Age at enrollment (OR 2.11, 95% CI 1.64-2.72), child baseline BMI (OR 3.37, 95% CI 2.51-4.54), and parent baseline BMI (OR for a 6-unit change 1.36, 95% CI 1.09-1.70) were significantly associated with the odds of becoming obese for children.

Conclusions
The combination of child age, parent BMI, and child overweight as predictors of child obesity suggest a paradigm of family-centered obesity prevention beginning in early childhood, emphasizing the relevance of child overweight as a phenotype highly predictive of child obesity.