Harris R E, Zang E A, Wynder E L
Division of Epidemiology, American Health Foundation, New York, NY 10017.
Int J Epidemiol. 1990 Jun;19(2):240-6. doi: 10.1093/ije/19.2.240.
The association between breast cancer risk and oral contraceptive use was examined in 401 breast cancer patients and 519 hospital controls interviewed in New York City during 1979-1981. Control subjects were ascertained utilizing variable ratio matching to the cases (2:1 or 1:1) by sex, age, hospital, and time of diagnosis. No evidence of a positive association was found between cancer risk and the duration of use in either parous or nulliparous women. The odds ratios obtained by comparing users to non-users in women under 50 years of age after adjusting for other risk factors were 0.8 (95% CI = 0.4-1.4) for less than five years duration and 0.4 (95% CI = 0.2-0.8) for five or more years duration (P less than 0.05 when tested for decreasing trend). There was also no evidence of effect modification between oral contraceptive use and other breast cancer risk factors (viz. family history, nulliparity, late age at first pregnancy, or abstention from breastfeeding). Our results do not indicate that the use of oral contraceptives increases the risk of breast cancer.
1979年至1981年期间，在纽约市对401名乳腺癌患者和519名医院对照者进行了访谈，以研究乳腺癌风险与口服避孕药使用之间的关联。通过性别、年龄、医院和诊断时间，采用可变比例匹配（2:1或1:1）的方法确定对照对象。在经产妇或未产妇中，均未发现癌症风险与使用时长之间存在正相关的证据。在调整其他风险因素后，对50岁以下女性使用者与非使用者进行比较，使用时长少于5年的优势比为0.8（95%置信区间=0.4-1.4），使用时长为5年或更长时间的优势比为0.4（95%置信区间=0.2-0.8）（经趋势递减检验，P<0.05）。口服避孕药的使用与其他乳腺癌风险因素（即家族史、未生育、初孕年龄较大或不进行母乳喂养）之间也没有效应修饰的证据。我们的结果并未表明使用口服避孕药会增加患乳腺癌的风险。
