Betel Quid Chewing and Upper Aerodigestive Tract Cancers: A Prospective Cohort Study in Khon Kaen, Thailand

Background: This study aimed to determine the association between betel quid chewing and the occurrenceof upper aerodigestive tract (UADT) cancers.
Methods: A cohort of 17,388 subjects, recruited and interviewedover the 1990-2001 period, in Khon Kaen, Thailand, was followed up until 2011. The data were linked to theKhon Kaen Population-Based Cancer Registry.
Results: The prevalence of betel quid chewing was 15.9%, with afemale predominance (97.7%); the mean age of chewers was 57.7 years (SD 6.6). The overall incidence of UADTcancers from the cohort was 14.7 per 100,000 person-years, whereas the incidence among the chewers was 45.7.Betel nut chewing was the only major risk factor for UADT cancers in this population (HR=5.26, 95%CI=2.51-11.0), while weak associations were found for tobacco smoking and alcohol (HR=1.16, 95%CI=0.45-3.01 and 1.47,95%CI=0.72-3.03 respectively).
Conclusions: We found betel quid chewing to be a main risk factor for UADTcancers, resulting in a higher incidence in females. However, further study is required to explore the potentialr isk factors among non-chewers, non-smokers, and non-drinkers