Dental visits and colon-rectum cancer: A nationwide population-based nested case-control study in Taiwan.

Background/purpose: Although oral health and systemic diseases are closely associated, little is known about the utilization of ambulatory dental visits in patients prior to diagnosis of colon-rectum cancer (CRC). In this study, a nested case-control study based on the population-based health claim database was conducted to clarify the relationship between dental visits and CRC in Taiwan. Materials and methods: From the Longitudinal Health Insurance Research Database 2010 (LHIRD 2010), we identified 4787 patients who were newly diagnosed with CRC from 2005 to 2013. We also recruited 19,148 control subjects matched in a 1:4 ratio based on sex and age at the index date from LHIRD 2010. Both groups were retrospectively traced back to 1997 to obtain any records of ambulatory dental visits that occurred within 8 years prior to the index date. ICD-9 codes 520-529 for diseases of oral cavity, salivary glands, and jaw were defined as dental visits. Results: The mean frequency of dental visits within 8 years prior to index date among patients with CRC were significantly higher than the control group ( Conclusion: Our results indicate that the utilization of ambulatory dental visits is significantly increased in patients with CRC prior to its diagnosis. Certain co-morbidities may also affect the frequency of dental visits and the occurrence of CRC.