Periodontal Disease and Breast Cancer Risk: Results from the Nurses' Health Study.

BACKGROUND: While periodontal disease has been linked to increased cancer risk, studies regarding an association with breast cancer are limited.
METHODS: We examined the relationship between self-reported diagnosis of periodontal bone loss and incidence of breast cancer in a large, prospective cohort study, the Nurses' Health Study (1998-2014). We calculated HRs using Cox proportional hazards modeling, adjusting for risk factors common to both periodontal disease and breast cancer.
RESULTS: During 1,023,647 person-years of follow-up, 5,110 of breast cancer cases were reported. We observed no association between periodontal disease and overall breast cancer risk (HR, 1.02; 95% confidence interval: 0.94-1.10); the association was not modified by smoking status, or other breast cancer risk factors or by breast tumor subtypes.
CONCLUSIONS: We did not observe any association between periodontal disease and breast cancer risk. IMPACT: Given inconsistent findings in the literature, further research with standardized clinical measures of periodontitis is warranted. ©2021 American Association for Cancer Research.