Association of Metabolic Syndrome with the Risk of Head and Neck Cancer: A 10-Year Follow-Up Study of 10 Million Initially Healthy Individuals

SIMPLE SUMMARY: The global incidence of metabolic syndrome is on the rise, and its association with various types of cancer has been established. However, research into an association between metabolic syndrome and the incidence of head and neck cancer has been relatively limited. This population-based study aimed to report on the association of metabolic syndrome with head and neck cancer and individual subtypes of cancers. The study found that participants with metabolic syndrome exhibited a higher risk of developing head and neck cancer, particularly oral cavity and laryngeal cancers. The elevated levels of fasting glucose and blood pressure present in individuals with metabolic syndrome were independently associated with an increased risk of head and neck cancer. The results of this study could assist with etiological investigations and prevention strategies. ABSTRACT: The aim of this national population-based retrospective study was to analyze the relationship between MetS and the incidence of HNC. In this Korean population-based cohort study, 9,598,085 subjects above the age of 20 were monitored from 1 January 2009 to 31 December 2018. In the study population, a total of 10,732 individuals were newly diagnosed with HNC during the 10-year follow-up. The hazard ratio (HR), after adjusting for age, gender, smoking status, alcohol intake, and exercise, indicated that participants with MetS were at a 1.06-fold (95% CI: 1.01–1.10) higher risk of having HNC than those without MetS. Participants with MetS showed an increased risk of developing oral cavity cancer (HR, 1.12; 95% CI, 1.03–1.23) and laryngeal cancer (HR, 1.18; 95% CI, 1.09–1.27). Among the components of MetS, elevated fasting glucose (HR = 1.04, 95% CI: 1.00–1.08) and elevated blood pressure (HR = 1.08, 95% CI: 1.04–1.13) were significantly associated with an increased HR for HNC in an adjusted multivariable model. The association between HNC and MetS remained significant even among individuals who had never smoked or were ex-smokers (HR: 1.09; 95% CI: 1.04–1.15), as well as those who did not drink or were mild drinkers (HR: 1.07; 95% CI: 1.02–1.12). The findings of this cohort study suggest MetS was associated with an increased risk for some types of HNCs. The results of this study could assist with etiological investigations and prevention strategies.