Objectives: Children of immigrants have higher risk of overweight/obesity. The study objectives were to identify BMI-trajectories and their predictors in children of Australian immigrants from low-and-middle-income-countries.
Methods: Data of 4349 children aged 2-3 years were drawn from the Birth cohort of the “Longitudinal Study of Australian Children”. Trained interviewers measured height and weight of children at 2-yearly intervals until they were 10–11 years. BMI was calculated according to the International Obesity Taskforce cut-off-points. Maternal immigrant status was determined by Australian Bureau of Statistics and Human Development Index criteria. Latent Class Growth Analysis was used to estimate distinct BMI-trajectories. Multinominal logistic regression analysis was used to identify risk-factors with each BMI-trajectory.
Results: Six BMI-trajectories were identified: persistent high-risk (10%; n=394); persistent moderate-risk (5%; n=223); persistent low-risk (68%; n=3002); delayed-risk (6%; n=248); gradual-risk (8%; n=336); and declining-risk (3%; n=146) BMI-trajectories. Children of mothers from low-and-middle-income-countries were more likely to have persistent moderate-risk, persistent high-risk or gradual-risk BMI-trajectory and less likely to have low-risk BMI-trajectory. High birth weight was associated with persistent moderate-risk and persistent high-risk; low family socio-economic-position with persistent high-risk and gradual-risk; non-participation in organized sports with persistent moderate-risk; and high screen-time with gradual-risk BMI-trajectory. We found that 4-7 years was a critical period for developing overweight/obesity in these children.
Conclusion: Disparities in child weight by maternal immigrant status were present from an early age. Promoting physical activities from an early age may lower excess overweight/obesity and associated cardio-metabolic risks in children of immigrants from low-and-middle-income-countries.