Study and reference | Pack-years of smoking | |
---|---|---|
 | Controls (N) | COPDs (N) |
Bergen cohort from Pillai et al [26] | 19 ± 13*(810) | 32 ± 19*(823) |
Copenhagen City Heart Study from Kaur-Knudsen et al [25] | NR | NR |
COPDGene study from Kim et al [24] | 52 ± 29*(335) | 37 ± 19*(507) |
COPACETIC cohort from Lambrechts et al [23] | 38.0 (28.0-46.2) (295) | 38.7 (29.7-49.5)(161) |
LEUVEN cohort from Lambrechts et al [25] | 42.3 (30.0-50.5) (184) | 40.0 (30.0-57.0) (475) |
NETT/NAS cohorts from Pillai et al [26] | 40 ± 28*(472) | 66 ± 30*(389) |
New Zealand study from Young et al [27] | 40 ± 19*(488) | 47 ± 20*(458) |