Table I.
Characteristics of NSCLC cases and controls
| Characteristic | Total sample |
Whitea |
Blacka |
||||||
| Cases N = 504 (48.9%) | Controls N = 527 (51.1%) | P-value | Cases N = 389 (48.9%) | Controls N = 406 (51.7%) | P-value | Cases N = 115 (48.7%) | Controls N = 121 (51.3%) | P-value | |
| Age (mean, SD) | 59.7 (9.2) | 59.0 (9.5) | 0.27 | 60.3 (9.1) | 59.5 (9.4) | 0.19 | 57.4 (9.3) | 57.5 (9.8) | 0.94 |
| Current BMI (mean, SD) | 26.2 (5.8) | 29.4 (7.3) | <0.0001 | 26.0 (5.6) | 28.6 (6.6) | <0.0001 | 26.7 (6.6) | 32.2 (8.6) | <0.0001 |
| Education, n (%) | <0.0001 | <0.0001 | 0.48 | ||||||
| Less than high school | 94 (18.7) | 45 (8.5) | 65 (16.8) | 22 (5.4) | 29 (25.2) | 23 (19.0) | |||
| High School graduate or equivalent | 200 (39.8) | 168 (31.9) | 166 (42.8) | 132 (32.5) | 34 (29.6) | 36 (29.8) | |||
| Some college | 209 (41.5) | 314 (59.6) | 157 (40.4) | 252 (62.1) | 52 (45.2) | 62 (51.2) | |||
| Smoking status, n (%) | <0.0001 | <0.0001 | <0.0001 | ||||||
| Never | 40 (7.9) | 259 (49.5) | 32 (8.2) | 204 (50.6) | 8 (7.0) | 55 (45.9) | |||
| Exsmokerb | 159 (31.6) | 164 (31.4) | 166 (34.2) | 130 (32.3) | 26 (22.6) | 34 (28.3) | |||
| Current smoker | 305 (60.5) | 100 (19.1) | 224 (57.6) | 69 (17.1) | 81 (70.4) | 31 (25.8) | |||
| Pack-years (mean, SD) | 46.9 (29.2) | 25.3 (22.8) | <0.0001 | 51.2 (29.6) | 26.2 (22.8) | <0.0001 | 32.7 (22.9) | 22.6 (22.7) | 0.005 |
| Exposure to ETS as a child, n (%) | 0.04 | 0.11 | 0.18 | ||||||
| No | 108 (21.4) | 142 (26.9) | 80 (20.6) | 103 (25.4) | 28 (24.3) | 39 (32.2) | |||
| Yes | 396 (78.6) | 385 (73.1) | 309 (79.4) | 303 (74.6) | 87 (75.7) | 82 (67.8) | |||
| Years (mean, SD among exposed) | 16.5 (3.8) | 15.8 (6.1) | 0.08 | 16.8 (3.5) | 16.0 (6.5) | 0.07 | 16.5 (4.8) | 16.2 (4.5) | 0.76 |
| Household exposure to ETS as an adult, n (%) | <0.0001 | <0.0001 | 0.94 | ||||||
| No | 98 (19.5) | 177 (33.7) | 69 (17.8) | 146 (36.0) | 29 (25.2) | 31 (25.6) | |||
| Yes | 405 (80.5) | 349 (66.3) | 319 (82.2) | 259 (64.0) | 86 (74.8) | 90 (74.4) | |||
| Years (mean, SD among exposed) | 27.0 (15.2) | 19.8 (13.3) | <0.0001 | 28.0 (14.6) | 19.9 (13.2) | <0.0001 | 23.7 (16.7) | 19.8 (13.8) | 0.09 |
| Work exposure to ETS, n (%) | <0.0001 | <0.0001 | 0.05 | ||||||
| No | 108 (21.5) | 184 (35.0) | 80 (20.6) | 140 (34.6) | 28 (24.6) | 44 (36.4) | |||
| Yes | 395 (78.5) | 341 (65.0) | 309 (79.4) | 264 (65.4) | 86 (75.4) | 77 (63.6) | |||
| Years (mean, SD among exposed) | 16.4 (10.7) | 13.2 (11.0) | <0.0001 | 16.7 (11.0) | 12.9 (11.1) | <0.0001 | 15.4 (9.4) | 14.3 (10.7) | 0.47 |
| History of chronic obstructive lung disease, n (%)c | <0.0001 | <0.0001 | 0.38 | ||||||
| No | 346 (68.7) | 453 (86.0) | 252 (64.8) | 349 (86.0) | 94 (81.7) | 104 (86.0) | |||
| Yes | 158 (31.3) | 74 (14.0) | 137 (35.2) | 57 (14.0) | 21 (18.3) | 17 (14.0) | |||
| First-degree family history of lung cancer, n (%) | <0.0001 | <0.0001 | 0.01 | ||||||
| No | 374 (74.2) | 463 (87.9) | 287 (73.8) | 356 (87.7) | 87 (75.6) | 107 (88.4) | |||
| Yes | 130 (25.8) | 64 (12.1) | 102 (26.2) | 50 (12.3) | 28 (24.4) | 14 (11.5) | |||
| HRT use, n (%) | 0.13 | 0.25 | 0.24 | ||||||
| Ever | 233 (46.2) | 269 (51.0) | 203 (52.3) | 177 (43.6) | 30 (26.1) | 40 (33.1) | |||
| Never | 270 (53.8) | 258 (49.0) | 185 (47.7) | 229 (56.4) | 85 (73.9) | 81 (66.9) | |||
a
White cases were missing one response for education, one for household exposure to ETS as an adult and one response for HRT use. White controls were missing three responses for smoking status and one response for household exposure to ETS as an adult. Black cases were missing one response for work exposure to ETS and black controls were missing one response for smoking status.
b
Quit smoking at least 2 years prior to diagnosis (cases) or interview (controls).
c
Chronic bronchitis, chronic obstructive pulmonary disease or emphysema.