Baseline characteristics of the yellow-stained finger cases and of control smokers
| Variables | Cases (n=49) | Controls (n=49) | p Value* |
|---|---|---|---|
| Matching | |||
| Median (IQR) age (years) | 62 (50–69) | 59 (50–69) | 0.65† |
| Male | 32 (65) | 32 (65) | 0.99 |
| Median (IQR) height (cm) | 170 (165–177) | 170 (165–175) | 0.84† |
| Median (IQR) pack-years smoked‡ | 50 (40–61) | 46 (38–58) | 0.20† |
| Median (IQR) predicted FEV1 (L)§ | 3.3 (2.4–3.8) | 3.2 (2.4–3.7) | 0.60† |
| Diagnosis category on admission¶ | |||
| Cardiovascular | 11 (22) | 15 (31) | 0.48 |
| Neurological | 7 (14) | 6 (12) | 0.99 |
| Oncology | 8 (16) | 6 (12) | 0.79 |
| Infectious disease | 5 (10) | 5 (10) | 0.99 |
| Traumatology | 6 (12) | 5 (10) | 0.99 |
| Others | 12 (24) | 12 (24) | 0.99 |
Values are numbers (percentage) unless stated otherwise.
IQR 25–75%.
*McNemar and exact test unless stated otherwise.
†Paired Wilcoxon sign-rank test.
‡Number of packs smoked in a day multiplied by the number of years spent smoking or sum of the different PYs throughout life if the consumption was higher or lower for more than a year's duration.
§Predicted FEV1 calculated according to the third National Health and Nutrition Examination Survey formula.19
¶Category of main diagnosis claimed on the exit chart.
FEV1, maximal forced expiratory volume in 1 s; PY, pack-year unit.