Table 1.
Baseline demographics and smoking history of the analysis cohort
| Baseline smoking history category | N | Median (25/75th) pack-years | Median (25/75th) CPD* | Median age, y (25/75th) | Median duration of smoking, y (25/75th) | % male | % Non-Hispanic white |
|---|---|---|---|---|---|---|---|
| Never smoker | 69 182 | N/A | N/A | 62 (58/67) | N/A | 38.8 | 88.5 |
| Current smoker, 30+ pack-years | 12 243 | 53 (43/72) | 20 (20/30) | 60 (57/65) | 43 (39/47) | 58.3 | 88.5 |
| Current smoker, 20–29.9 pack-years | 2283 | 22.5 (21/25) | 10(10/10) | 63 (60/67) | 44 (41/48) | 40.4 | 74.2 |
| Former smoker, 30+ pack-years & quit within 15 years | 18 114 | 51 (39/71) | 30 (20/40) | 62 (58/66) | 37 (32/42) | 62.1 | 91.0 |
* Cigarettes per day (CPD) was assessed in categories of 1–10, 11–20, 21–30, 31–40, 41–60, 61–80, >80. High value of range was used to compute CPD and pack-years.