world cancer report - iarc

ipated, is primarily attributable to young
people taking up the habit. Factors that
lead youngsters to start smoking include
smoking by parents and siblings and, most
significantly, peer pressure. Thus, smoking
by a best friend, or belonging to a group
where a majority smoke has a strong influence
[14]. The task of promoting nonsmoking
as a healthy lifestyle choice may
be accorded to teachers in general or to
Nicotine replacement therapy (NRT)
Gum (49 trials, N=16,706)
Patch (30 trials, N=15,677)
Intranasal spray (4 trials, N=877)
Inhaler (4 trials, N=976)
Sublingual tablet (2 trials, N=488)
AII NRT formulations
132 Prevention and screening
0.7 1 1.5 2
specialist educators. The goal must be to
prevent schoolchildren from starting to
smoke. Therefore, programmes must be
initiated early (before the age at which
experimentation is likely to start) and to
achieve a positive impact, an intensive programme
over several years should be integrated
into the school curriculum. Limited
interventions by health professionals from
outside the school setting cannot be
Odds ratio (95% C.I.)
1.63 (1.49 - 1.79)
1.73 (1.56 - 1.93)
2.27 (1.61 - 3.20)
2.08 (1.43 - 3.04)
1.73 (1.07 - 2.80)
1.71 (1.60 -1.82)
Fig. 4.4 Meta-analysis of nicotine replacement therapy trials; nicotine replacement therapy increases the
chance of quitting smoking by more than one and a half times. T. Lancaster et al. (2000) BMJ 321, 355-358, with permission
from the BMJ Publishing Group.
expected to have a lasting impact. Unless
interventions are strengthened with inclusion
of booster sessions, the positive
effects of most programmes will wear off.
However, even under the best conditions,
there seems little room for optimism.
Under real life conditions, it has proved
impossible to replicate the encouraging
results from pilot trials [15]. While effort
continues to be directed at health promotion
campaigns aimed at youth, there is
abundant recognition of the worth and
need for development of campaigns directed
towards women [16] and members of
communities in the developing world [17].
Smoking cessation
Preventing young people from starting
smoking would cut the number of deaths
related to tobacco, but not until after
2050. Quitting by current smokers is the
only way in which tobacco-related mortality
can be reduced in the medium term. The
risk of lung cancer decreases inversely
with the time since quitting smoking (Fig.
4.3). About 20% of smokers are prepared
to make an active attempt to quit in the
immediate future (within 30 days) [18].
Fig. 4.5 Death rates at ages 35-69 from lung cancer in smokers versus non-smokers in various parts of China, 1986-88. Although lung cancer rates show wide
variation between cities and between urban and rural areas, lung cancer mortality in smokers was consistently about three times higher in smokers than in nonsmokers.
Lung cancer mortality rates in some areas greatly exceed those found in the USA, which in 1990, similarly standardized for age, were 1.4 per 1,000
male and 0.6 per 1,000 female smokers, and 0.1 per 1,000 male or female non-smokers. R. Peto et al. (1999) Nature Medicine 5: 15-17.