Table 1.
Baseline characteristics of Lung Health Study Cohort according to sex at the time of randomization.
| Women (n = 2185) | Men (n = 3702) | p-Value | |
|---|---|---|---|
| Age (years) | 48.55 ± 6.56 | 48.42 ± 6.98 | 0.71 |
| Body mass index (kg/m2) | 24.19 ± 3.98 | 26.37 ± 3.66 | < 0.001 |
| Smoking (pack-years) | 36.37 ± 16.63 | 42.86 ± 20.07 | < 0.001 |
| Cigarettes per day | 28.89 ± 11.79 | 32.68 ± 13.24 | < 0.001 |
| Age at smoking initiation (years) | 18.13 ± 3.92 | 17.09 ± 3.78 | < 0.001 |
| FEV1 (litres)b | 2.17 ± 0.36 | 3.08 ± 0.49 | < 0.001 |
| Subjects in GOLD 1 grade | 986 (45.13%) | 1728 (46.68%) | 0.26 |
| Subjects in GOLD 2 grade | 1198 (54.83%) | 1970 (53.21%) | 0.24 |
| Bronchodilator response (% of baseline FEV1) | 4.31 ± 5.35 | 4.27 ± 4.95 | 0.99 |
| SIA | 769 (35.19%) | 1192(32.20%) | < 0.05 |
| SIP | 706 (32.31%) | 1256(33.93%) | 0.21 |
| PC 20 (mg/ml) | 6.35 ± 5.44 | 8.62 ± 6.61 | < 0.001 |
| O'Connor Slopea | − 18.33 ± 28.25 | − 9.47 ± 19.35 | < 0.001 |
Data are presented as mean ± SD for continuous variable and number of subjects (% column totals).
Abbreviations: FEV1, forced expiratory volume in 1 s; GOLD, Global initiative for chronic Obstructive Lung Disease; PC, provocation concentration at which there is 20% fall in FEV1; SIA, special intervention + Atrovent; SIP, special intervention + placebo.
a
O'Connor Slope is defined as the percentage of decline of FEV1 from the post-saline value to the value measured after the final methacholine dose administered divided by the final cumulative methacholine dose administered.
b
All values are post-bronchodilator.