Time trends of obesity in pre-school children in China
from 1989 to 1997.
Luo J, Hu FB.
Takemi Program, Harvard School of Public Health, Boston, Massachusetts
02115, USA.
OBJECTIVE: To examine predictors and time trends of obesity in pre-school
children in China. DESIGN: This study was based on data from China Health
and Nutrition Survey, a longitudinal survey from 1989 to 1997. SUBJECTS: For
cross-sectional analysis, we included 944, 1058, 903 and 483 children aged
2-6 y in 1989, 1991, 1993 and 1997, respectively. For longitudinal analysis,
we included 944 children and 3146 measurements during four time periods.
MEASURES: Overweight and obesity according to age- and sex-specific BMI
cut-off points proposed by International Obesity Task Force. RESULTS: The
overall prevalence of obesity increased from 4.2% in 1989 to 6.4% in 1997
among children aged 2-6 y. The increase largely occurred in urban areas,
where the prevalence of obesity increased from 1.5% in 1989 to 12.6% in 1997
and prevalence of overweight increased from 14.6 to 28.9% at the same period.
Longitudinal analysis shows BMI increased by 0.2 kg/m2 per year in urban
areas and 0.1 kg/m2 per year in rural areas. In multivariate analysis,
overweight in early childhood (2-6 y), parental overweight, high income and
urban areas independently predicted overweight at age 10-14 y. CONCLUSION: A
substantial increase in overweight and obesity among children aged 2-6 y was
observed in urban areas in China from 1989 to 1997. Overweight in early
childhood significantly predicted overweight during adolescence. Urgent
public health strategies are needed to prevent childhood obesity in China.