Risk factors for breast cancer in Turkish women: a hospital-based case-control study.

The aim of this study was to investigate the association between risk factors and breast cancer in Turkish women. In a hospital-based case-control study in Istanbul, 405 patients with histologically confirmed breast cancer were compared with 1050 controls, who were admitted to different departments of the same hospital. Unadjusted odds ratios (ORs) and 95% confidence intervals (CIs) for each risk factor were obtained from logistic regression analyses. Risk factors for breast cancer were found to be early menarche age (OR 3.87, 95% CI 2.46-6.08), use of alcohol (OR 3.87, 95% CI 1.79-8.37), history of diabetes (OR 3.31, 95% CI 2.36-4.64) or hypertension (OR 3.44, 95% CI 2.07-5.71), oral contraceptive use (OR 1.98, 95% CI 1.38-2.85) and hormone replacement therapy (HRT) use (OR 1.94, 95% CI 1.15-3.29). The findings of the present study indicated that history of diabetes or hypertension, use of alcohol, oral contraceptive and HRT, never having breastfed and delayed age at first birth associated with changing of lifestyle led to an increased risk of breast cancer in Turkish women.