Obesity is a significant risk factor for breast cancer in Arab women

Background: Breast cancer (BC) is the most common malignancy and the leading cause of cancer-related death amongst women worldwide. The risk factors of this disease are numerous, and their prevalence varies between racial and ethnic groups as well as geographical regions. Therefore, we sought to delineate the association of socio-demographic, reproductive and life-style related risk factors with breast cancer in the Arab population. Methods: Unmatched case-control study was conducted in the kingdom of Saudi Arabia using 534 cases of histologically confirmed breast cancer and 638 controls. Controls were randomly selected from primary health care visits and were free of breast cancer. Unconditional logistic regression analysis was performed to estimate odds ratios (ORs) and to examine the predictive effect of each factor on risk for BC. All study participants were interviewed by trained interviewers at hospital (cases) or at primary health care centers (controls). Results: A total of 1172 women were eligible for this study, of which 281 (24.0%) were aged <= 35 years, 22.9% illiterate, 43.6% employed, 89.5% married, and 38.1% were obese. Grade III tumors constituted 38.4% of cases. Tumor stage I was 7.5%; II, 50.7%; II, 30.9%; IV, 11.1%. We have shown strong association between breast cancer among Arab females and obesity (OR = 2.29, 95% CI 1.68 - 3.13), positive family history of breast cancer (OR = 2.31, 95% CI 1.60 - 3.32), the use of hormonal replacement therapy (OR = 2.25, 95% CI 1.65 - 3.08), post-menopause (OR = 1.72, 95% CI 1.25 - 2.38), lack of education (OR = 9.09, 95% CI 5.88 - 14.29), and never breastfeed (OR = 1.89, 95% CI 1.19 - 2.94). Conclusion: These results indicate the presence of classical risk factors established in the western countries, and also some specific ones, which may result from genetic and/or environmental factors. Thereby, these findings will be of great value to establish adequate evidence-based awareness and preventative measures in the Arab world.