[Analysis on adulthood weight change in adults in China].

Objective: To understand the characteristics of adulthood weight change through the analysis on data from China Kadoorie Biobank (CKB) Study of 0.5 million adults from ten areas in China. Methods: An electronic questionnaire was used to collect the information about the body weight at age 25 years, social-demographic characteristics and lifestyle of the study subjects and their body weight were measured. After excluding the adults with self-reported histories of coronary heart disease, stroke, cancer or diabetes and those who had no data of body weight at age 25 years and those aged outside of 35-70 years, a total of 360 903 adults were included in the analysis. Adulthood weight change were defined as difference value between current body weight and body weight at age 25 years. Results: The mean adulthood weight change of the participants was 4.9 kg. The adults living in urban area showed more body weight increase compared with those living in rural area, so did the adults in northern area compared with those in southern area. Among the ten areas in China, Qingdao reported the highest adulthood weight increase (9.3 kg), and Gansu reported the lowest adulthood weight increase (1.5 kg). Older adults had higher BMI at early adulthood (25 years old), but the adults aged 45-50 years had the highest adulthood body weight increase. Adults with higher educational level, higher household income level, but lower physical activity level had more body weight increase, while current smokers, farmers and workers had less body weight increase. BMI at age 25 years was negatively associated with adulthood body weight change, but current BMI was positively associated with adulthood body weight change (P<0.001). Conclusion: Adulthood body weight change varied greatly among population with different demographic characteristics and lifestyle and in ten areas in China.目的： 描述中国慢性病前瞻性研究（CKB）队列人群的成年期体重变化状况及其地区和人群差异。 方法： 采用自行设计的电子问卷进行面对面基线调查，收集调查对象25岁体重以及社会人口学特征、生活方式等信息，并测量调查对象当前体重。本研究剔除基线自报患有慢性病、重要变量缺失、年龄<35岁或者>70岁的个体，最终纳入360 903名研究对象。成年期体重变化定义为当前体重与25岁时体重的差值。 结果： 研究对象成年期平均增重4.9 kg。城市地区人群增重高于农村地区，北方地区高于南方地区。10个项目点中，青岛项目点成年期平均增重量最大（9.3 kg），甘肃项目点最低（1.5 kg）。出生年代越早者，25岁BMI较高。成年期增重量在45~50岁组最高。在调整了年龄和地区后，不同文化程度、职业、家庭年收入、体力活动水平、吸烟情况人群的成年期体重变化的分布差异有统计学意义（P<0.001）。25岁时BMI水平越高者，成年期增重量越小；当前BMI水平越高者，成年期增重量越大（趋势P<0.001）。 结论： CKB项目10个地区研究人群成年期体重变化存在明显的地区和人群差异。.