Poor oral health affects survival in head and neck cancer

Poor oral health has emerged as a risk factor for squamous cell carcinoma of the head and neck (HNSCC) but its impact on survival has not been examined. We sought to estimate the impact of oral health indicators on survival in a population-based HNSCC cohort.

Cases (n=1381) and age-, sex- and race-matched controls (n=1396) were participants in the Carolina Head and Neck Cancer Epidemiologic Study (CHANCE). Vital status was determined via linkage with the National Death Index. Survival was considered at 5years post-diagnosis or study-enrollment for controls. Oral health was assessed using self-reported indicators including frequency of routine dental exams and tooth brushing. We used Kaplan-Meyer analyses and Cox regression to estimate adjusted hazard ratios (HR) and 95% confidence intervals (CI).

Routine dental visits during the preceding 10years were associated with decreased mortality risk (>10 visits: HR=0.6, 95% CI=0.4-0.8) after adjusting for confounders. This effect was most pronounced for oral cavity cancer-(e.g., >10 visits: HR=0.4, 95% CI=0.2-0.9). Dental visits were also positively associated with survival among controls. No other routine health screening (e.g., eye exams) was associated with survival.

We found significant associations between markers of oral health and survival among both HNSCC cases and controls. This association was most pronounced for sites closer to the dentition. Oral health may have a direct effect on tumor biology due to the associated immune or inflammatory response. It may also represent a proxy for wellness or unmeasured social determinants of health.