Table 2.
Demographic Characteristics of Participants in a Pooled Analysis of Previous Lung Diseases and Lung Cancer Risk, International Lung Cancer Consortium, 1984–2011
| Cases (n = 24,607) |
Controls (Noncases) (n = 81,829) |
|||||
|---|---|---|---|---|---|---|
| No. | % | Mean (SD) | No. | % | Mean (SD) | |
| Age at diagnosisa, years | 61.1 (10.9) | 56.4 (8.1) | ||||
| Age group, years | ||||||
| <50 | 4,434 | 18.0 | 12,135 | 14.8 | ||
| 51–60 | 6,713 | 27.3 | 46,522 | 56.9 | ||
| 61–70 | 8,392 | 34.1 | 19,156 | 23.4 | ||
| >70 | 5,068 | 20.6 | 4,016 | 4.9 | ||
| Sex | ||||||
| Male | 15,394 | 62.6 | 41,964 | 51.3 | ||
| Female | 9,213 | 37.4 | 39,865 | 48.7 | ||
| Ethnicity | ||||||
| White/Caucasian | 21,030 | 85.5 | 74,890 | 91.5 | ||
| Black/African-American | 1,379 | 5.6 | 1,698 | 2.1 | ||
| Asian | 561 | 2.3 | 574 | 0.7 | ||
| Hispanic/Latino | 313 | 1.3 | 629 | 0.8 | ||
| Other/unknown | 1,324 | 5.4 | 4,038 | 4.9 | ||
| Smoking status | ||||||
| Never smoker | 2,719 | 11.0 | 29,884 | 36.5 | ||
| Ever smoker | 21,888 | 88.9 | 51,945 | 63.5 | ||
| Former smoker | 13,113 | 53.3 | 27,022 | 52.0 | ||
| Current smoker | 8,775 | 35.7 | 24,923 | 48.0 | ||
| Pack-years of smokingb | 44.1 (28.0) | 28 (16.8) | ||||
| <15 | 5,191 | 21.1 | 41,719 | 51.0 | ||
| 15–<30 | 4,383 | 17.8 | 13,477 | 16.5 | ||
| 30–45 | 6,179 | 25.1 | 21,168 | 25.9 | ||
| >45 | 8,854 | 36.0 | 5,465 | 6.7 | ||
| Histologic typec | ||||||
| Adenocarcinoma | 6,684 | 27.1 | ||||
| Squamous cell carcinoma | 4,685 | 19.0 | ||||
| Small cell lung cancer | 1,810 | 7.4 | ||||
| Large cell lung cancer | 824 | 3.3 | ||||
Abbreviation: SD, standard deviation.
a Age at baseline in the cohort study.
b Among ever smokers only.
c The remaining cases had either mixed or other histologic types.