Risk Factors Associated with Breast Cancer among Women in Warri and lbadan, Nigeria

Ojectives Breast cancer is a common cause of death among Nigerian women. Identifying some of the risk factors is vital to strategic intervention in breast cancer control. This study was carried out to determine risk factors associated with breast cancer among women in two referral hospitals in Nigeria.Methods A case control study was carried out among 266 women aged 20-80 years. The participants with breast cancer and the comparison group (controls) were matched in the ratio of 1:3 respectively for age and duration of stay in the area of residence. A semi-structured questionnaire was used to collect data on socio-demographic characteristics, family history of breast cancer, dietary pattern, nutritional status, physical activity and environmental factors.ResultsThe mean age of the respondents was 48. 7±11.8 years. Family history of breast cancer was reported by 6.2% of the cases and 5.0% of control group. Dietary pattern revealed that the cases (69.2%) significantly had high risk consumption pattern for high calorie containing foods than the controls (54. 7%). Significantly more of the controls than cases had engaged in good physical exercise (17.9% versus 6.2%). The odds of developing breast cancer was four times higher among women who reported daily exposure to fumes from automobiles and electricity generating plants than those who were rarely exposed (0R=4.40, C/=1.25-15.57) and seven times higher among women who reported occasional exposure to wastes from operating industries than those who were rarely exposed (0R=6.91, C/=2.87- 16.66).Conclusion Major risk factors for breast cancer among women in this study were lack of exercise,high calorie intake, and environmental pollutants. Health education to improve knowledge of self-protection against pollutants and healthy dietary habits may reduce risk of breast cancer.Keywords: Breast cancer; Risk factors; Environmental pollutants; Dietary pattern; Nigeria