National Institute of Health and Nutrition, National Institutes of Biomedical Innovation, Health and Nutrition, Tokyo, Japan.
Int J Obes (Lond). 2019 Apr;43(4):751-760. doi: 10.1038/s41366-018-0307-7. Epub 2019 Jan 18.
BACKGROUND/OBJECTIVES: To assess longitudinal changes in the first incidence of overweight and obesity and associated factors from preschool to primary school age in Japan.
SUBJECTS/METHODS: We obtained individual-level data from the "Longitudinal Survey of Newborns in the 21st Century" on children born in Japan in 2001. This analysis included 15,427 children (7951 boys and 7476 girls) with complete anthropometric data reported annually from age 42 months to 12 years. We followed the criteria of the International Obesity Task Force to define overweight and obesity. We assessed annual and cumulative incidence proportions and estimated odds ratios for the first incidence at preschool age (42-66 months) and primary school age (7-12 years), using multivariable logistic regression.
The annual incidence of overweight and obesity combined was 3.8% at age 54 months (3.5% in boys, 4.2% in girls), and 1.2% at age 12 years (1.6% in boys, 0.7% in girls). The cumulative incidence was 19.7% at age 12 years (21.9% in boys, 17.3% in girls). Odds ratios (95% confidence intervals) of incidence for girls compared with boys were 1.28 (1.12-1.46) at preschool age and 0.62 (0.55-0.68) at primary school age. Other associated factors at preschool age included birth month, birthweight, gestational length, region and municipality of residence, living with grandparents, and behavioral factors (bedtime hours, television viewing time, and skipping breakfast). These associations persisted at primary school age except birthweight and gestational length and associated factors covered maternal education, living without siblings, and school travel mode.
The first incidence decreases from preschool to primary school age and follows different age trajectories for boys and girls in a high-income population with low levels of childhood overweight and obesity. Policy-makers should consider such age-based changes in incidence and associated factors to target appropriate groups for primary prevention.
背景/目的：评估日本从学前到小学年龄超重和肥胖首次发病的纵向变化及其相关因素。
受试者/方法：我们从日本 2001 年出生的“21 世纪新生儿纵向调查”中获取了个体水平的数据。本分析包括 15427 名儿童（7951 名男孩和 7476 名女孩），他们在 42 个月至 12 岁时每年报告完整的人体测量数据。我们根据国际肥胖工作组的标准定义超重和肥胖。我们使用多变量逻辑回归评估了学前年龄（42-66 个月）和小学年龄（7-12 岁）首次发病的年度和累积发病比例，并估计了发病比值比。
54 个月时超重和肥胖的年发病率为 3.8%（男孩 3.5%，女孩 4.2%），12 岁时为 1.2%（男孩 1.6%，女孩 0.7%）。12 岁时的累积发病率为 19.7%（男孩 21.9%，女孩 17.3%）。与男孩相比，女孩在学前年龄和小学年龄的发病比值比分别为 1.28（1.12-1.46）和 0.62（0.55-0.68）。学前年龄的其他相关因素包括出生月份、出生体重、胎龄、居住地区和市町村、与祖父母同住以及行为因素（睡眠时间、看电视时间和不吃早餐）。除了出生体重和胎龄以及包括母亲教育、无兄弟姐妹居住和学校交通方式等相关因素外，这些关联在小学年龄阶段仍然存在。
在超重和肥胖儿童比例较低的高收入人群中，首次发病从学前到小学年龄逐渐减少，且男孩和女孩的发病轨迹不同。决策者应考虑发病和相关因素的这种年龄变化，以便针对适当的人群进行初级预防。
