Association of high birth weight with overweight and obesity in Chinese students aged 6–18 years: a national, cross-sectional study in China

BACKGROUND: The prevalence of childhood overweight and obesity in China has drastically increased 57 times over the past 30 years, and to control birth weight is an effective way to reduce the risk of overweight and obesity across the life course. OBJECTIVE: This paper aimed to evaluate the association of high birth weight (HBW) with overweight and obesity in Chinese students aged 6–18 years. METHODS: All students with HBW (n=4981) aged 6–18 years were selected from a cross-sectional survey from seven provinces of China, and 4981 other students with normal birth weight (NBW) were randomly sampled with matched gender, age and province. Anthropometric parameters were measured and characteristics were collected by questionnaires. Multiple logistic regression was used to estimate the OR of overweight and obesity with HBW, unadjusted and adjusted for confounding factors. RESULTS: Participants with HBW revealed higher body mass index in childhood. The prevalence of overweight and obesity was significantly higher in the HBW group than in the NBW group (overweight 15.3% vs 13.1%, p<0.05; obesity 16.9% vs 10.6%, p<0.05), and the results were similar for overweight in all age groups except age 6–7, age 14–15 and age 16–18. Additionally, HBW was positively associated with overweight (OR=1.230; 95% CI 1.056 to 1.432) and obesity (OR=1.611; 95% CI 1.368 to 1.897) after adjustment for covariates. CONCLUSIONS: HBW leads to an increased risk of overweight and obesity in childhood; thus, measures to control birth weight, such as controlling gestational weight gain, should be taken from the earliest beginning of life. TRIAL REGISTRATION NUMBER: NCT02343588; Post-results.