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.