Table 1

Distribution of demographic, smoking, and clinical variables

Cases (n = 491)Controls (n = 497)P
Sex, n (%)
 Males294 (60.0)244 (49.1)
 Females197 (40.0)253 (50.9)<0.001
Age (mean ± SD)
 Overall61.3 ± 10.557.7 ± 11.0<0.0001
 Males62.1 ± 9.958.1 ± 9.8<0.001
 Females60.0 ± 11.257.2 ± 12.00.005
Smoking status, n (%)
 Never37 (7.5)144 (29.0)
 Former176 (35.9)174 (35.0)
 Current278 (56.6)179 (36.0)<0.0001
Current smokers
 Smoking duration (mean ± SD)40.2 ± 11.335.4 ± 11.5<0.001
 No. cigarettes/day (mean ± SD)23.3 ± 12.514.6 ± 9.0<0.001
 Pack-years (mean ± SD)49.8 ± 64.332.0 ± 75.60.009
 Mentholated cigarette use,*n (%)128 (48.5)106 (59.9)0.019
Former smokers
 Smoking duration (mean ± SD)33.3 ± 14.025.1 ± 12.9<0.0001
 No. cigarettes/day (mean ± SD)20.4 ± 12.817.4 ± 13.00.029
 Pack-years (mean ± SD)36.0 ± 27.823.4 ± 21.9<0.0001
 Years since smoking cessation (mean ± SE)6.4 ± 10.010.5 ± 11.60.029
 Age at smoking cessation (mean ± SE)53.5 ± 12.245.1 ± 11.4<0.001
 Mentholated cigarette use,* n (%)70 (40.7)82 (47.4)0.210
Environmental exposures (%+)
 Asbestos210 (44.4)151 (30.8)<0.0001
 Wood dusts178 (39.7)130 (27.1)<0.0001
 Fibers51 (11.5)37 (7.8)0.058
 SVF77 (17.5)35 (7.5)<0.0001
 Benzene122 (27.3)97 (20.6)0.020
 Toluene/xylene155 (34.4)118 (25.0)0.002
 Dry cleaning22 (5.2)13 (2.8)0.069
 Vehicle exhaust122 (27.9)113 (23.9)0.178
 Pesticides44 (10.4)32 (6.9)0.061
 Glues and plastics55 (12.4)41 (8.6)0.117
Comorbidities (%+)
 Asthma64 (13.0)62 (12.5)0.697
 COPD81 (16.5)10 (2.0)<0.0001
 Hay fever65 (13.2)89 (17.9)0.070
Family history among first degree
 Relatives (%+) lung cancer78 (15.9)64 (12.9)0.178
 Smoking related (%+)105 (21.4)95 (19.1)0.375
Histology,* n (%)
 Adenocarcinoma168 (38.7)
 Squamous cell144 (33.2)
 Other NSCLC75 (17.3)
 Small cell26 (6.0)
 Other lung cancer21 (4.8)
Stage,* n (%)
 I32 (11.2)
 II21 (7.4)
 III116 (40.7)
 IV116 (40.7)

Abbreviations: NSCLC, non–small cell lung cancer; %+, percent positive.

  • *Sum may not add up to total due to missing data.