Breast Cancer Risk Factors: A Case-Control Study in Iranian Women

Background: breast cancer is the most frequent malignancy and the leading causeof cancer-related death among women all around the world. in iran, the mean age ofthe patients is approximately 10 years younger than that in other countries. weconducted the present study to assess the risk factors of breast cancer among iranianwomen in mashhad.method: this case-control study was carried out between february 2016 andjanuary 2018 on 460 women (230 cases and 230 controls) in the academic hospitalsof mashhad. the data from our cases and controls were collected and analyzed usingspss version 18.0 software (spss inc., chicago, il, usa). we employed logisticregression models and frequency tables to estimate odds ratio (or) and to examinethe predictive effect of each factor on breast cancer risk. p < 0.05 was considered tobe significant.results: according to multivariate analysis, there was significant associationsbetween breast cancer risk and body mass index (bmi) (odds ratio (or), 1.1; 95%confidence interval (ci), 1.0-1.2), age at menarche (or, 0.56; 95% ci, 0.47-0.68),menopausal age (or, 1.1; 95% ci, 1.0-1.1), family history of non-breast malignancies(or, 7.9; 95% ci, 2.2-21.1), and oral contraception pills (or, 3.1; 95% ci, 8.34-1.16).conclusion: this study revealed that age at menarche, family history of nonbreastcancer malignancies, bmi, menopausal age, and oral contraception pills weresignificantly associated with breast cancer.