中文摘要：

目的 探讨体力活动与乳腺癌发病的关系。方法 采用以医院为基础的病例对照研究,调查某大学2所附属医院2012年4月-2014年12月间确诊的25-70岁549例乳腺癌患者和同期同医院就诊的549例非肿瘤患者的体力活动情况和相关危险因素。采用非条件Logistic回归模型分析体力活动与乳腺癌发病的关系。结果校正各种混杂因素后,非职业性体力活动与乳腺癌发病风险降低有关（OR=0.69,95%CI：0.48-1.00）;与不参加体育活动者相比,参加体育活动对乳腺癌发病有保护作用（OR=0.61,95%CI：0.43-0.87）;与久坐不动的职业相比,轻度职业活动对乳腺癌发病有保护作用（OR=0.67,95%CI：0.47-0.97）,而家务活动与乳腺癌发病风险无关。不同雌激素受体（estrogen receptor,ER）和孕激素受体（progesterone receptor,PR）状态的亚组分析中,非职业性体力活动与ER＋/PR＋乳腺癌的发病风险降低有关。结论 非职业性体力活动、体育活动和轻度职业活动对女性乳腺癌有保护作用。

英文摘要：

Objective To assess the association between physical activity and risk of breast cancer. Methods A hospital-based case-control study was conducted in two affiliated hospitals of a university between April 2012 and December 2014. Face to face interviews were completed among 549 breast cancer cases and 549 controls. Physical activity and poten- tial risk factors of breast cancer were collected by using a standard questionnaire. Multivariate unconditional Logistic regres- sion model was used to estimate the association between physical activity and breast cancer risk. Results A lower risk for breast cancer was observed far highest levels of non-occupational physical activity （ OR =0.69,95% CI：0. 48-1.00 ） , far recreational activity （ OR =0. 61, 95% CI：0.43-0. 87 ） , as well as for standing occupational activity （ OR = 0. 67, 95% CI：0.47-0. 97）, while household activity showed null result. Non-occupational physical activity showed reverse association with ER ＋/PR ＋ breast cancer risk. Conclusions Non-occupational physical activity, recreational activity and standing occupational activity are inversely associated with breast cancer risk.