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Background: Although the increase in risk of developing breast, ovarian, and prostate cancer in BRCA1 and BRCA2 mutation carriers has been studied extensively, its impact on mortality is not well quantified. Further, possible effect of BRCA mutations on non-cancer mortality risk has not been examined., Methodology/principal Findings: Using mortality data from the relatives of 5,287 genotyped participants, of whom 120 carried a BRCA Ashkenazi Jewish founder mutation, in a community-based study of the Ashkenazi Jewish population in the Washington D.C area, we examined the association between the three Ashkenazi BRCA founder mutations and risk of overall and non-cancer mortality. To examine risks beyond the established effects of these mutations, we analyzed the data excluding both deaths and follow-up times after reported diagnosis of melanoma and cancer of the breast, ovary, prostate, and pancreas. Using an extension of the kin-cohort method that accounts for informative censoring, we estimated that, in the absence of breast, ovarian, and pancreatic cancers, and melanoma, female carriers had a life expectancy that was 6.8 years lower (95% CI: 1.2-10.5) than non-carriers. In male mutation carriers, the reduction in life expectancy, in the absence of prostate and pancreatic cancers and melanoma, was 3.7 (95% CI: -0.4, 6.8) years. When deaths and follow-up times after any cancer diagnosis were excluded, the difference in life expectancy was 5.7 years for women (95% CI: -0.1, 10.4) and 3.7 years for men (95% CI: -0.4, 6.9). An overall test of association for men and women together showed a statistically significant association between BRCA1/2 mutations and increased non-cancer mortality (p = 0.024)., Conclusions/significance: These findings suggest that there may be unknown effects of BRCA1/2 mutations on non-neoplastic diseases that cause death at older ages.

Background: Younger age at first birth and greater parity generally reduce the risk of developing breast cancer, but whether this reduced risk holds in women with a mutation in the BRCA1 or BRCA2 gene is unknown., Methods: In a Washington DC community-based study conducted in 1996, we tested 5318 Ashkenazi Jews for three BRCA1/2 founder mutations and identified 120 mutation carriers. Applying an extension of the "kin-cohort" analysis, we compared the effects of reproduction on breast cancer risk in carriers and noncarriers. We also used a case-case analysis among 288 participants who had been diagnosed with breast cancer., Results: In noncarriers, the estimated relative risk (RR) of breast cancer rose 5% with each 5-year increment in age at first birth (RR = 1.05; 95% confidence interval [CI] = 0.97-1.15). By contrast, the estimated risk in mutation carriers fell with each 5-year increment in age (RR = 0.65; 95% CI = 0.37-1.16). Among the 288 participants who were breast cancer survivors themselves, the comparison of carriers with noncarriers also showed no protection associated with early birth in the presence of a mutation in BRCA1 or BRCA2., Conclusions: It is not yet clear whether the recognized breast cancer risk factors operate in the same way in women who carry a mutation in the BRCA1 or BRCA2 genes.