Tobacco and Public Health - TCSC Indonesia

Studies in India: Oral cancer is the most common cancer in India, where large quantities
of smokeless tobacco are used (Jayant and Deo 1986). Smokeless tobacco use is considered
to be a major risk factor for the high incidence rate of oral cancer in this country. The
study by Nandakumar et al. (1990) reported an increased risk of oral cancer among pan
tobacco chewers in both males and females, and no increased risk among pan chewing
without tobacco. A dose–response was observed for years of chewing, number of times of
chewing per day, and period of retaining the pan in the mouth. A linear test for trend was
statistically significant (P < 0.001) in all three instances. Compared to those with no history
of chewing tobacco, the ORs were 8.5 (95% CI 4.7–15.2) for those who did not chew
during sleep, and 17.7 (95% CI 8.7–36.1) for those with a history of chewing during sleep.
Rao et al. (1994) also reported a significant association between tobacco chewing
and risk of oral cancer (OR = 3.0, 95% CI 2.3–3.7), and the risk increased with increasing
frequency (P trend < 0.001). For chewers who chewed tobacco 21–30 times per day,
the OR was 10.7 times higher than that for non-chewers. Several other earlier case–
control studies (Sanghvi et al. 1955; Wahi et al. 1965; Jussawalla and Deshpande 1971;
Notani 1988) and follow-up studies (Bhargava et al. 1975; Gupta et al. 1980) from
different parts of India have also provided unequivocal evidence between chewing
tobacco and oral cancer risk, and this risk appeared to be even higher among those
who began the habit at a younger age (Jayant et al. 1971).
Other countries: Franco et al. (1989) reported no association between use of smokeless
tobacco, either as snuff or tobacco chewing, and risk of oral cancer in Brazil.
However, the number of subjects who used tobacco in this form was small (9 cases and
13 controls). In Sudan, however, an increased risk of oral cancer was reported among
those who used toombak, a coarse powder made of dried tobacco leaves, and the risk
was found to be higher for anatomic sites (buccal cavity, floor of mouth, and lip) where
tissues come in direct contact with the product (Idris et al. 1995).
Tobacco and alcohol interaction
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A number of studies from different populations or racial groups have investigated the
interaction between tobacco and alcohol on the risk of oral cancer, and most of them
have concluded that the effects of tobacco and alcohol are certainly more than additive
and seem to be consistent with multiplicative, with some suggesting a supramultiplicative
effect (Negri et al. 1993; De Stefani et al. 1998; Garrote et al. 2001).
Studies, which presented the joint distribution of cases and controls for each combination
of smoking and alcohol consumption with the corresponding ORs, have shown a
sharp increase in the risk for those with the heaviest levels of consumption of both
products compared to the lowest levels of consumption of both products. The OR for the
highest levels of consumption of both products reached as high as 305 (Baron et al. 1993).
A strong interaction between tobacco and alcohol in the risk of oral cancer was
observed no matter if the relationship is expressed by lifetime consumption of the