Periodontal disease and risk of non‐Hodgkin lymphoma in the Health Professionals Follow‐Up Study

Periodontal disease is a chronic inflammatory condition that has been associated with chronic diseases, including cancer. In an earlier prospective cohort analysis within the Health Professionals Follow‐Up Study (HPFS), we observed a 31% higher risk of non‐Hodgkin lymphoma (NHL) among participants with severe periodontal disease at baseline. Here, we extend the study with an additional 8 years of follow‐up, and conduct analyses with updated periodontal disease status and NHL subtypes. The HPFS is an ongoing prospective cohort study of 51,529 men in the USA Between baseline in 1986 and 2012, 875 cases of NHL were diagnosed, including 290 chronic lymphocytic leukemia/small lymphocytic lymphomas (CLL/SLL), 85 diffuse large B‐cell lymphomas and 91 follicular lymphomas. We performed multivariable Cox proportional hazards regression to evaluate associations of interest. History of periodontal disease at baseline was positively associated with risk of NHL overall (hazard ratio (HR) = 1.26, 95% confidence interval (CI): 1.06–1.49) and CLL/SLL (HR = 1.41, 95% CI: 1.04–1.90). With updated periodontal status, HRs were 1.30 (95% CI: 1.11–1.51) for NHL overall and 1.41 (95% CI: 1.08–1.84) for CLL/SLL. In contrast, after adjusting for periodontal disease, tooth loss was inversely associated with NHL, suggesting that other causes or consequences of tooth loss may have different implications for NHL etiology. Our findings suggest that periodontal disease is a risk factor for NHL. Whether periodontal disease is a direct or indirect cause of NHL, or is a marker of underlying systemic inflammation and/or immune dysregulation, warrants further investigation.