Sociodemographic and Reproductive Risk Factors for Breast Cancer: A Case-Control Study in the Setif Province, Northern Algeria

The age-standardized rate of breast cancer (BC) increased nearly nine-fold in the last 30 years in Setif, Algeria. A case-control study was carried out to investigate the role of sociodemographic characteristics and reproductive factors in the etiology of BC in this young Arab/Berber population of Setif. Methods: Cases were 612 women with incident BC admitted to major teaching and general hospitals of Setif during 2012–2017. Controls were 615 women admitted for acute, non-neoplastic conditions to the same hospital network of cases. Information was elicited using a standardized questionnaire. Odds ratios (ORs) and 95% confidence intervals (CIs) were computed after allowance for age and education. Results: Significant associations with BC risk emerged for family history of BC (OR= 4.15 for yes vs. no; 95%CI: 2.22-7.77), for the generation of oral contraceptive used (OR=1.57 for II-generation vs. III-generation; 95%CI:1.01-2.44), and education (OR=0.63 for >11 years vs. no schooling; 95%CI: 0.46-0.86). Conversely, parity and body mass index were not associated with BC risk, whereas a late age at menarche was linked with a non statistically significant BC risk (OR=1.20 for >15 vs. <13 years; 95%CI:0.86-1.66). These results were consistent in strata of menopausal status. Conclusion(s): Some of the expected risk factors (e.g., low education levels and type of oral contraceptives) were associated with elevated BC risks also in Setif, and these findings offer further support to primary preventive efforts already carried on in Algeria. Conversely, no association emerged for other well established risk factors (e.g., body mass index)