Table 2.
Baseline clinical characteristics from medical records
| Total (n=754) | Low FEV1% predicteda (n=297) | High FEV1% predicteda (n=457) | |
|---|---|---|---|
| Spirometry test results | |||
| Postbronchodilator FEV1 % predicted, mean (SD, median) | 56.6 (19.96, 56) | 37.2 (8.38, 39) | 69.1 (14.51, 66) |
| Postbronchodilator FEV1/FVC ratio (%), mean (SD, median) | 53.6 (11.07, 55) | 45.5 (10.71, 44) | 58.8 (7.58, 60) |
| Documented asthma diagnosis, n (%) | |||
| Yes | 142 (18.8) | 51 (17.2) | 91 (19.9) |
| No | 232 (30.8) | 84 (28.3) | 148 (32.4) |
| Unknown/not documented | 380 (50.4) | 162 (54.5) | 218 (47.7) |
| Documented dyspnea, n (%) | |||
| Yes | 552 (73.2) | 230 (77.4) | 322 (70.5) |
| No | 82 (10.9) | 21 (7.1) | 61 (13.3) |
| Unknown/not documented | 120 (15.9) | 46 (15.5) | 74 (6.2) |
| Documented smoking status, n (%) | |||
| Current smoker | 163 (21.6) | 58 (19.5) | 105 (23.0) |
| Former smoker | 408 (54.1) | 162 (54.5) | 246 (53.8) |
| Never-smoker | 35 (4.6) | 12 (4.0) | 23 (5.0) |
| Unknown/not documented | 148 (19.6) | 65 (21.9) | 83 (18.2) |
| Race, n (%) | |||
| Caucasian/white | 609 (80.8) | 246 (82.8) | 363 (79.4) |
| African-American/black | 18 (2.4) | 5 (1.7) | 13 (2.8) |
| Other | 5 (0.7) | 1 (0.3) | 4 (0.9) |
| Unknown/not documented | 122 (16.2) | 45 (15.2) | 77 (16.8) |
Note:
a
Low FEV1% predicted defined as FEV1 <50% predicted, high FEV1% predicted defined as FEV1 $50% predicted.
Abbreviations: FEV1, forced expiratory volume in 1 second; SD, standard deviation; FVC, forced vital capacity.