Table 3.

Cumulative Exposure to Cigarette Smoking and Associated Odds Ratios for Lung Cancer Among All Subjects and Ever Smokers, by Sex, the EAGLE Study, Lombardy, Italy, 2002–2005

Exposure Measure									Odds of Lung Cancer
	Cigarette Smoking Exposure								All Subjects				Ever Smokers
	Women				Men				Women		Men		Women		Men
	Cases		Controls		Cases		Controls		ORa	95% CI	OR	95% CI	OR	95% CI	OR	95% CI
	No.	%	No.	%	No.	%	No.	%
Categorical variable, pack-years
Never smoker	103	25.4	282	56.5	29	1.9	397	24.6	1.0	Referent	1.0	Referent
1–19	87	21.4	147	29.5	118	7.7	464	28.7	1.8	1.1, 2.9	5.9	3.7, 9.5	1.0	Referent	1.0	Referent
20–39	124	30.5	49	9.8	420	27.3	413	25.5	6.9	4.4, 10.7	18.2	12.0, 27.7	4.0	2.5, 6.4	3.1	2.3, 4.0
≥40	92	22.7	21	4.2	967	62.9	341	21.1	12.3	7.2, 21.2	42.2	28.1, 63.4	7.2	3.9, 13.4	7.1	5.4, 9.4
Data not available	0	0	0	0	3	0.2	2	0.1
Pinteractionb									0.0009c				0.55
Continuous variable (log10 (1 + pack-years/5))									11.3	7.6, 16.8	28.4	21.2, 38.1	37.5	15.3, 92.0	27.4	18.0, 41.7
Female sex-smoking interaction									0.39	0.24, 0.62			0.63	0.29, 1.37
Pinteractionb									<0.0001d				0.24

Abbreviations: CI, confidence interval; EAGLE, Environment and Genetics in Lung Cancer Etiology; OR, odds ratio.

^a ORs and 95% CIs from unconditional logistic regression models, adjusted for residential area, age, and years since quitting smoking.

^b P values were calculated from the likelihood ratio test or Wald test for the product of sex and pack-years (pack-years as a categorical or continuous (log₁₀ (1 + pack-years/5)) variable, respectively).

^c Negative female sex-smoking interaction coefficients for all of the pack-year categories evaluated.

^d Negative female sex-smoking interaction coefficient.