Department of Medical Laboratory Sciences, Student Research Committee, School of Allied Medical Science, Mazandaran University of Medical Sciences, Sari, Islamic Republic of Iran.
Gastrointestinal Cancer Research Center, Non-Communicable Diseases Institute, Mazandaran University of Medical Sciences, Sari, Islamic Republic of Iran.
Horm Mol Biol Clin Investig. 2020 Oct 21;41(4):/j/hmbci.ahead-of-print/hmbci-2020-0021/hmbci-2020-0021.xml. doi: 10.1515/hmbci-2020-0021.
Breast cancer is known as one of the deadliest forms of cancer, and it is increasing globally. There are a variety of proven and controversial risk factors for this malignancy. Herein, we aimed to undertake a systematic review and meta-analysis focus on the epidemiology of breast cancer risk factors in Iran.
We performed a systematic search via PubMed, Scopus, Web of Science, and Persian databases for identifying studies published on breast cancer risk factors up to March 2019. Meta-analyses were done for risk factors reported in more than one study. We calculated odds ratios (ORs) with corresponding 95% confidence intervals (CIs) using a fixed/random-effects models.
Thirty-nine studies entered into the meta-analysis. Pooling of ORs showed a significant harmful effect for risk factors including family history (OR: 1.80, 95%CI 1.47-2.12), hormonal replacement therapy (HRT) (OR: 5.48, 95%CI 0.84-1.74), passive smokers (OR: 1.68, 95%CI 1.34-2.03), full-term pregnancy at age 30 (OR: 3.41, 95%CI 1.19-5.63), abortion (OR: 1.84, 95%CI 1.35-2.33), sweets consumption (OR: 1.71, 95%CI 1.32-2.11) and genotype Arg/Arg (crude OR: 1.59, 95%CI 1.07-2.10), whereas a significant protective effect for late menarche (OR: 0.58, 95%CI 0.32-0.83), nulliparity (OR: 0.68, 95%CI 0.39-0.96), 13-24 months of breastfeeding (OR: 0.68, 95%CI 0.46-0.90), daily exercise (OR: 0.59, 95%CI 0.44-0.73) and vegetable consumption (crude OR: 0.28, 95%CI 0.10-0.46).
This study suggests that factors such as family history, HRT, passive smokers, late full-term pregnancy, abortion, sweets consumption and genotype Arg/Arg might increase risk of breast cancer development, whereas late menarche, nulliparity, 13-24 months breastfeeding, daily exercise and vegetable consumption had an inverse association with breast cancer development.
乳腺癌是最致命的癌症之一，且其在全球范围内的发病率正在上升。目前已经确定了多种乳腺癌的确切和有争议的危险因素。本研究旨在对伊朗乳腺癌危险因素的流行病学进行系统回顾和荟萃分析。
我们通过 PubMed、Scopus、Web of Science 和 Persian 数据库系统地检索了截至 2019 年 3 月发表的乳腺癌危险因素相关研究。对有多项研究报道的危险因素进行荟萃分析。我们使用固定/随机效应模型计算了相应的比值比（OR）及其 95%置信区间（CI）。
共有 39 项研究纳入荟萃分析。汇总 OR 显示，家族史（OR：1.80，95%CI 1.47-2.12）、激素替代疗法（HRT）（OR：5.48，95%CI 0.84-1.74）、被动吸烟（OR：1.68，95%CI 1.34-2.03）、30 岁足月产（OR：3.41，95%CI 1.19-5.63）、流产（OR：1.84，95%CI 1.35-2.33）、甜食摄入（OR：1.71，95%CI 1.32-2.11）和基因型 Arg/Arg（未经校正 OR：1.59，95%CI 1.07-2.10）等危险因素与乳腺癌发病风险呈正相关，而月经初潮晚（OR：0.58，95%CI 0.32-0.83）、未婚（OR：0.68，95%CI 0.39-0.96）、哺乳 13-24 个月（OR：0.68，95%CI 0.46-0.90）、每日运动（OR：0.59，95%CI 0.44-0.73）和蔬菜摄入（未经校正 OR：0.28，95%CI 0.10-0.46）等因素与乳腺癌发病风险呈负相关。
本研究表明，家族史、HRT、被动吸烟、足月晚产、流产、甜食摄入和基因型 Arg/Arg 等因素可能会增加乳腺癌发生的风险，而月经初潮晚、未婚、哺乳 13-24 个月、每日运动和蔬菜摄入与乳腺癌发生风险呈负相关。
