Periodontitis and breast cancer: A case‐control study

Abstract Objectives The aim of this case‐control study was to evaluate the association between periodontitis and breast cancer in a sample of adult Brazilian women. Methods This was a hospital‐based study, which included 67 cases and 134 controls (1:2). Women were selected consecutively between April, 2013 and June, 2015 among those attending the Department of Gynecology at the University Hospital of Santa Maria. Cases were selected among women diagnosed with breast cancer ( ICD ‐10 C50), and controls were matched for age (±2 years), and smoking status (never, former and current smoker). Conditional logistic regression was used to model the association between periodontitis and breast cancer with and without adjustment for potential confounders. Four case definitions for periodontitis were used. Results Cases had significantly greater clinical attachment loss than controls ( P =.04). After adjusting for important covariates, women diagnosed with periodontitis had two to three times higher odds of breast cancer than women without periodontitis depending on the case definition of periodontitis ( P <.05). Conclusions A significant association was observed between periodontitis and breast cancer.