Risk of head and neck cancer in patients with diabetes mellitus: a retrospective cohort study in Taiwan.

Importance: An increasing body of evidence suggests that certain types of cancers are more common in people with diabetes mellitus (DM). However, the risk of head and neck cancer (HNC) in patients with DM has seldom been explored.

Objective: To examine the risk of HNC in patients with DM.

Design, Setting, And Participants: In this retrospective cohort study using Taiwan's Longitudinal Health Insurance Research Database, we compared 89,089 patients newly diagnosed as having DM and controls without DM-related medical claims matched for comorbidities (obesity, coronary artery disease, hyperlipidemia, and hypertension), sex, and age. Patients were assessed from the index date until the end of follow-up on December 31, 2011, or until the patient was censored because of death.

Main Outcomes And Measures: The incidence of HNC at the end of 2011.

Results: The incidence of HNC was 1.47 times higher in patients newly diagnosed as having DM than was the risk of a first malignant tumor in the control group (adjusted hazard ratio [AHR], 1.48; 95% CI, 1.31-1.67). The risks of oral cancer (AHR, 1.74; 95% CI, 1.47-2.06), oropharyngeal cancer (AHR, 1.53; 95% CI, 1.01-2.31), and nasopharyngeal carcinoma (AHR, 1.40; 95% CI, 1.03-1.89) were significantly higher in patients with DM than in controls.

Conclusions And Relevance: Diabetes is associated with an increased risk of developing HNC. The risks of developing oral cavity cancer, oropharyngeal cancer, and nasopharyngeal carcinoma were significantly higher in patients with DM.