Table 1.
Baseline characteristics of study participants
| NT-proBNP < 900 pg/ml (n=849) |
NT-proBNP ≥ 900 pg/ml (n=202) |
p-value | |
|---|---|---|---|
| Demographics | |||
| Age | 65.2 ± 7.7 | 70.0 ± 6.8 | < 0.0001 |
| Female gender (%) | 334 (39.3%) | 101 (50.0%) | 0.006 |
| African-American (%) | 123 (14.5%) | 11 (5.5%) | 0.0005 |
| Smoking exposure | |||
| Smoking history (pack-years) | 52.4 ± 23.6 | 57.3 ± 26.8 | 0.009 |
| Current smoker (%) | 281 (33.1%) | 59 (29.2%) | 0.29 |
| Markers of respiratory health | |||
| Post-bronchodilator FEV1 (% predicted) | 61.4 ± 23.8 | 65.5 ± 20.1 | 0.02 |
| TLC (L) | 5.4 ± 1.3 | 5.0 ± 1.2 | < 0.0001 |
| CAT score | 14.9 ± 7.8 | 14.2 ± 7.9 | 0.28 |
| 6MWD (m) | 401.1 ± 118.5 | 384.3 ± 125.4 | 0.08 |
| ≥ 1 COPD exacerbation in past year (%) | 246 (29.0%) | 53 (26.2%) | 0.44 |
| Comorbidities | |||
| CAD (%) | 79 (9.5%) | 44 (22.0%) | < 0.0001 |
| MI (%) | 50 (6.0%) | 31 (15.5%) | < 0.0001 |
| CHF (%) | 16 (1.9%) | 13 (6.5%) | 0.0004 |
| Any of CAD, MI or CHF (%) | 109 (12.8%) | 62 (30.7%) | < 0.0001 |
| GERD (%) | 258 (30.4%) | 68 (33.7%) | 0.37 |
| Obesity (%) | 271 (31.9%) | 58 (28.7%) | 0.38 |
Data are presented as mean ± standard deviation for continuous variables and as number (percentage) for categorical variables. NT-proBNP, N-terminal pro-brain natriuretic peptide, FEV1, forced expiratory volume in one second; TLC, total lung capacity measured on chest CT; CAT, COPD Assessment Test; 6MWD, 6-minute walking distance; CAD, coronary artery disease; MI, myocardial infarction; CHF, congestive heart failure; GERD, gastroesophageal reflux disease; obesity defined as BMI > 30 kg/m2.