Although previous studies on tobacco and alcohol and the risk of
upper-aerodigestive-tract (UADT) cancers have clearly shown
dose-response relations with the frequency and duration of tobacco and
alcohol, studies on addiction to tobacco smoking itself as a risk factor
for UADT cancer have not been published, to our knowledge. The aim of
this report is to assess whether smoking addiction is an independent
risk factor or a refinement to smoking variables (intensity and
duration) for UADT squamous cell carcinoma (SCC) risk in the multicenter
case-control study (ARCAGE) in Western Europe. The analyses included
1,586 ever smoking UADT SCC cases and 1,260 ever smoking controls.
Addiction was measured by a modified Fagerstrom score (first cigarette
after waking up, difficulty refraining from smoking in places where it
is forbidden and cigarettes per day). Adjusted odds ratios (ORs) and
95% confidence intervals (95% CIs) for UADT cancers with addiction
variables were estimated with unconditional logistic regression. Among
current smokers, the participants who smoked their first cigarette
within 5 min of waking up were two times more likely to develop UADT SCC
than those who smoked 60 min after waking up. Greater tobacco smoking
addiction was associated with an increased risk of UADT SCC among
current smokers (OR=3.83, 95% CI: 2.56-5.73 for score of 3-7 vs. 0) but
not among former smokers. These results may be consistent with a
residual effect of smoking that was not captured by the questionnaire
responses (smoking intensity and smoking duration) alone, suggesting
addiction a refinement to smoking variables
