Family history and risk of breast cancer in Hispanic and non-Hispanic women: the New Mexico Women's Health Study

Objectives: Many epidemiologic studies have demonstrated that an increased risk of breast cancer is associated with positive family history of this di sease. Little information had been available on the relationship of breast cancer risk with family history in Hispanic women. To investigate the assoc iation of family history of breast cancer on the risk of breast cancer, we examined the data from the New Mexico Women's Health Study (NMWHS), a state wide case-control study. Methods: In this study 712 women (332 Hispanics and 380 non-Hispanic whites ) with breast cancer and 844 controls (388 Hispanics and 456 non-Hispanic w hites) were included. Conditional logistic regression was used to estimate the odds ratio (OR) and 95% confidence interval (95% CI), adjusted for soci odemographic, medical, and reproductive factors. Results: We found an increased risk in women with a history of breast cance r in one or more first-degree or second-degree relatives (OR = 1.5, 95% CI 1.2-1.9), first-degree relatives (OR = 1.3, 95% CI 1.0-1.8) and second-degr ee relatives (OR = 1.6, 95% CI 1.2-2.2). Hispanic women had higher risk est imates for a positive family history (OR = 1.7, 95% CI 1.1-2.5) than non-Hi spanic white women (OR = 1.4, 95% CI 1.0-2.0); however, the differences wer e not statistically significant. In both ethnic groups a higher risk was ob served in premenopausal women compared with postmenopausal women and women diagnosed with breast cancer before age 50years compared with older women. Conclusions: The results indicate that Hispanic women with a family history of breast cancer are at increased risk of breast cancer.