Relative risk of lung cancer by smoking status and lung function
| Factor | Person-years | n | Adjusting for age | Multivariate adjustment* |
|---|---|---|---|---|
| RR (95% CI) | RR (95% CI) | |||
| COPD, chronic obstructive pulmonary disease; FEV1, forced expiratory volume in 1 s; VC, vital capacity. | ||||
| *Rate ratios for smoking adjusted for age and lung function; rate ratios for lung function adjusted for age and smoking. | ||||
| †Normal: FEV1/VC >70%, %FEV1 >80%; mild COPD: FEV1/VC ⩽70%, %FEV1 >80%; moderate COPD: FEV1/VC ⩽70%, %FEV1 = 51–80%; severe COPD: FEV1/VC ⩽70%, %FEV ⩽50%; restrictive disease: FEV1/VC >70%, %FEV1 ⩽80%. | ||||
| Smoking | ||||
| Non-smoker | 1 205 114 | 42 | 1.0 | 1.0 |
| Former smoker | 329 236 | 69 | 2.7 (1.9 to 4.0) | 2.7 (1.8 to 3.9) |
| Current smoker (pack-years) | 971 491 | 723 | 12.9 (9.4 to 16.6) | 11.7 (8.5 to 15.9) |
| Current smoker, <50 | 495 987 | 115 | 9.1 (6.4 to 12.9) | 8.5 (5.9 to 12.1) |
| Current smoker, ⩾50 | 134 322 | 243 | 20.6 (14.8 to 28.7) | 18.0 (12.9 to 25.1) |
| Current smoker, unknown | 341 182 | 365 | 11.9 (8.6 to 16.3) | 10.9 (7.9 to 15.0) |
| Lung function† | ||||
| Normal | 2 326 915 | 570 | 1.0 | 1.0 |
| Mild COPD | 50 384 | 70 | 2.1 (1.6 to 2.7) | 1.5 (1.2 to 1.9) |
| Moderate COPD | 38 585 | 90 | 3.3 (2.6 to 4.1) | 2.1 (1.7 to 2.6) |
| Severe COPD | 3 828 | 15 | 4.1 (2.4 to 6.8) | 2.7 (1.6 to 4.6) |
| Restrictive lung disease | 86 129 | 89 | 2.8 (2.3 to 3.5) | 2.0 (1.6 to 2.5) |