Longitudinal analysis of growth trajectories in young children of Chinese-born immigrant mothers compared with Australian-born mothers living in Victoria, Australia.

Background: Chinese immigrants are the third largest immigrant group in Australia. Little is known about growth trajectories of their offspring when moving to a Western country. The aim was to describe the growth trajectories between birth to 3.5 years in children of Chinese-born immigrant mothers compared with Australian-born mothers living in Victoria, Australia.
Methods: Ten nurse measured weights and lengths from birth to 3.5 years were used to examine growth trajectory using linear spline multilevel models. Five knot points were identified at visit 2 (0.5 months), visit 4 (2 months), visit 5 (4.5 months), visit 8 (18 months) and visit 9 (25 months).
Results: Ethnic disparities in growth trajectories between these two groups were revealed in models adjusted for birth weight, sex and level of socioeconomic disadvantage. Children of Chinese-born compared with Australian-born mothers revealed different growth rates and significant differences in predicted mean body mass index Z score (zBMI) at all time points from birth to 44 months, except for 12 months. Specifically, when compared with children of Australian-born mothers, children of Chinese-born mothers started with lower predicted zBMI from birth until 0.5 months, had a higher zBMI from 1 to 8 months and a lower zBMI from 12 to 44 months. Early and sharp acceleration of growth was also observed for children of Chinese-born mothers (0.5-2 months) when compared with children of Australian-born mothers (2-18 months).
Conclusion: Differences in growth trajectories exist between young children of Chinese-born and Australian-born mothers. Better understanding of these ethnically patterned growth trajectories is important for identifying key opportunities to promote healthy growth in early life.
Competing Interests: Competing interests: None declared.
(© Author(s) (or their employer(s)) 2021. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)