Bottom Line: Poor oral health was associated with increased risk of pancreatic cancer in African-American women.
Journal in Which the Study was Published: Cancer Epidemiology, Biomarkers & Prevention, a journal of the American Association for Cancer Research.
Author: Julie R. Palmer, ScD, MPH, professor and associate director, Slone Epidemiology Center at Boston University.
Background: Pancreatic cancer is a rare but highly fatal cancer type, with less than 10 percent of patients surviving more than five years after a diagnosis. Its incidence is higher in African-Americans than in U.S. whites, and the reasons for the disparity are unknown.
"Several previous studies in white populations had shown an association between poor oral health and pancreatic cancer," Palmer explained. "We wanted to examine the association in African-Americans, who have a higher prevalence of poor oral health." Palmer said higher rates of poverty among African-Americans may limit access to dental care.
How the Study Was Conducted: Palmer and colleagues used data from the Black Women's Health Study, which enrolled 59,000 African-American women aged 21 to 69 in 1995. Information was updated every other year, adding data on cancers and other health conditions, smoking, alcohol, weight, and other variables. Through 2016, follow-up was about 85 percent complete.
At several points during the follow-up period, the researchers asked questions to ascertain whether the women were suffering from periodontal disease and/or tooth loss. Questions varied slightly by year, but they typically asked if they had suffered gingivitis, bleeding gums, or tooth loss. Researchers determined the number of cancer cases through cancer registries and the National Death Index. During the study period 2007 through 2016, 78 cases of pancreatic cancer occurred.
Results: Women who reported tooth loss without periodontal disease were more than twice as likely to have been diagnosed with pancreatic cancer. The association was the strongest among women who had lost at least five teeth. Those who reported periodontal disease but no tooth loss were 77 percent more likely to have been diagnosed with pancreatic cancer than those who reported neither periodontal disease nor tooth loss. Those who reported periodontal disease and tooth loss were 58 percent more likely to have been diagnosed with pancreatic cancer.
Author's Comments: "These findings, taken together with what we know about patterns of oral health in the United States, suggest that the existing racial disparities in pancreatic cancer and mortality could be reduced by improving oral care for African-Americans," Palmer said.
Further research is necessary to understand the mechanisms behind the increased risk, Palmer noted.
Study Limitations: Palmer pointed out that pancreatic cancer is a rare disease, and even in a large study population, only 78 cases were diagnosed. The small sample size did not allow stratification of cases beyond smoking status.
Funding & Disclosures: This study was funded by the National Institutes of Health. Palmer declares no conflicts of interest.