Table 1. Characteristics of randomly selected lung adenocarcinoma and squamous cell carcinoma cases and matched cancer-free controls from the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study.
| Characteristic | Subgroup | Adenocarcinoma | Squamous cell carcinoma | ||
| Cases | Controls* | Cases | Controls* | ||
| Median age at baseline serum draw | 58.0 | 58.0 | 59.8 | 59.6 | |
| Median date of baseline serum draw | 1/23/1987 | 1/23/1987 | 1/22/1987 | 1/23/1987 | |
| Treatment group, N (%) | |||||
| Placebo | 84 (24.0) | 94 (26.9) | 75 (21.4) | 97 (27.7) | |
| Beta-carotene | 88 (25.1) | 85 (24.3) | 110 (31.4) | 87 (24.9) | |
| Alpha-tocopherol | 89 (25.4) | 83 (23.7) | 80 (22.9) | 86 (24.6) | |
| Alpha-tocopherol+beta-carotene | 89 (25.4) | 88 (25.1) | 80 (22.9) | 85 (24.3) | |
| Education level, N (%) | |||||
| Primary school or lower | 282 (80.6) | 275 (78.6) | 291 (83.1) | 288 (82.3) | |
| High school or higher | 68 (19.4) | 75 (21.4) | 59 (16.9) | 62 (17.7) | |
| Obesity, N (%) | |||||
| BMI† <25 | 178 (50.9) | 136 (38.9) | 157 (44.9) | 129 (36.9) | |
| BMI† 25–<30 | 144 (41.1) | 160 (45.7) | 141 (40.3) | 165 (47.1) | |
| BMI† ≥30 | 28 (8.0) | 54 (15.4) | 52 (14.9) | 56 (16.0) | |
| Median cigarettes per day (range) | 20 (5–55) | 20 (5–75) | 20 (5–60) | 20 (5–60) | |
| Median pack-years (range) | 42 (1–121) | 35 (1–101) | 42 (4–111) | 35 (1–123) | |
| Asthma, N (%) | 14 (4.0) | 8 (2.3) | 19 (5.4) | 7 (2.0) | |
| Emphysema, N (%) | 32 (9.1) | 24 (6.9) | 36 (10.3) | 21 (6.0) | |
| Bronchitis, N (%) | 41 (11.7) | 27 (7.7) | 47 (13.4) | 25 (7.1) | |
| Median number of lost teeth (range) | 4 (1–5) | 4 (1–5) | 4 (2–5) | 4 (1–5) | |
| Dentures, N (%) | 238 (68.0) | 216 (61.9) | 261 (74.8) | 241 (68.9) | |
*Controls matched with cases on age at baseline serum draw and date of baseline serum draw.
†
BMI = body mass index.