肥胖与大肠高风险腺瘤发病风险研究

目的 探讨肥胖与大肠高风险腺瘤发病风险的关系。方法 以参加2008年上海市社区大肠癌筛查研究中的45~74岁的社区居民为研究对象，收集筛查前风险因素和筛查后肠镜诊断结果，并结合人工主动随访收集大肠高风险腺瘤发病的结局信息，采用多因素Cox比例风险回归模型分析BMI与大肠高风险腺瘤发病的风险比（HR）和95% CI。结果 20 811名研究对象共计随访122 739.36人年，平均随访时间为5.87年，共收集大肠高风险腺瘤657例。与体重正常者相比，肥胖者（BMI≥28.0 kg/m²）大肠高风险腺瘤发病风险增加21%，调整年龄、性别、大肠癌家族史、文化程度、婚姻状况、生活方式特征如吸烟、饮酒、脂肪类食物摄入、油炸或腌制类食物摄入及蔬菜水果摄入情况等因素后，肥胖者发生大肠高风险腺瘤的HR值为1.25（95% CI：1.04~1.51）。进一步按年龄、性别及大肠癌家族史进行分层分析后发现，在男性、>60岁人群中，肥胖者与体重正常者相比，大肠高风险腺瘤的发生风险更大（男性：HR=1.57，95% CI：1.20~2.04；>60岁人群：HR=1.63，95% CI：1.23~2.16）。结论 肥胖是大肠高风险腺瘤发病风险独立的危险因素，发病风险随BMI的增加而增加。

Association between obesity and risk for colorectal advanced adenoma

Objectives To understand the association between obesity and the risk for colorectal advanced adenoma. Methods Community residents aged 45 to 74 who had participated in the Shanghai community-based colorectal cancer (CRC) screening project in 2008 were included in our study. Anthropometries information including body weight, height and risk factors for colorectal advanced adenoma were collected. Results on colonoscopic diagnosis and personal health records were used for supplementary outcome information retrieval. Multivariate Cox proportional hazard regression models were used to evaluate the hazard ratio (HR) and 95% CI of obesity on the risk for colorectal advanced adenoma. Results 20 811 residents were followed up for 122 739.36 person- years, with a median follow-up time of 5.87 years. A total of 657 cases of advanced adenomas were identified. After adjusting for potential confounding risk factors such as age, sex, family history of CRC, level of education, marriage, cigarette smoking, alcohol drinking, foods intake including fat, fried or pickled, vegetables and fruits etc., the HR was 1.25 (95% CI: 1.04-1.51) for obese people when compared with the normal weight persons. Further stratified analysis by age, gender and family history of CRC, results showed that obese people had a much higher risk of colorectal advanced adenoma than those with normal weight (male: HR=1.57, 95% CI: 1.20-2.04; more than 60- year-old: HR=1.63, 95% CI: 1.23-2.16). Conclusion Data from this large scale population-based study revealed that obesity might be an independent risk factor for colorectal advanced adenoma and the risk increases along with the increase of BMI in China.