Prospective community-population-registry-based cohort study of the association between betel-quid chewing and cardiovascular disease in men in Taiwan (KCIS no. 19)

Background: Betel-quid chewing, a recognized risk factor for oral cancer, was shown to be a contributory cause of metabolic syndrome in humans, which implies a greater likelihood of developing cardiovascular disease (CVD) among those with the betel habit. Objective: This study investigated the effect of betel chewing on the risk of developing overt CVD. Design: We used the prospective cohort data derived from a community-population-registry-based integrated screening program to quantify the effect of betel-quid chewing on the incidence of newly diagnosed CVD by classifying the study population into either exposed or nonexposed groups according to chewing status at baseline. We then followed the group free of CVD at recruitment for 2.72 y (SD = 1.52 y) to learn of new cardiovascular events. Proportional hazards regression modeling was used to estimate the magnitude of the effect of betel-quid chewing on CVD. Results: After control for age and education level, ever chewers had a 23% (95% CI: 11%, 37%) greater risk of developing CVD than did never chewers; ever chewers were still at greater risk of developing CVD by 24% (95% CI: 11%, 39%) after further adjustment for age, education, and other significant confounders. Significant dose-response relations were found for betel-quid chewing (P < 0.05, trend test) after adjustment for other significant variables. Conclusion: The habit of chewing betel nut was shown to have independent dose effects to predict increases in the risk of CVD in men, with the use of a prospective community-population-registry-based cohort study.