Table 2.
Baseline Characteristics of Individuals by Significant Transition Status
| Characteristic | Had Significant Transition During Follow-up? |
P Value | |
|---|---|---|---|
| No (n = 1,436) | Yes (n = 349) | ||
| Sex (female) | 717 (50.3) | 189 (54.2) | .216 |
| Race (Black) | 351 (24.6) | 140 (40.1) | < .001 |
| Age, y | 59.4 ± 8.3 | 58.2 ± 8.3 | .019 |
| BMI, kg/m2 | 28.7 ± 5.7 | 29.6 ± 6.5 | .010 |
| Current smoker | 598 (41.9) | 194 (55.6) | < .001 |
| Pack-years | 42.1 ± 23.0 | 41.4 ± 23.1 | .609 |
| FEV1 % predicted | 81.4 ± 23.7 | 85.1 ± 15.3 | .005 |
| FVC % predicted | 91.0 ± 16.6 | 90.5 ± 15.9 | .612 |
| Percent emphysemaa | 6.0 ± 8.5 | 3.0 ± 4.6 | < .001 |
| Percent gas trappingb | 20.1 ± 17.3 | 13.1 ± 11 | < .001 |
| Pi10a | 2.2 ± 0.6 | 2.2 ± 0.5 | .845 |
| Total lung volume % predicteda | 106.3 ± 17.0 | 101.9 ± 17.1 | < .001 |
| Pectoralis muscle area, cm2,c | 41 ± 14.7 | 43.2 ± 17 | .018 |
| SGRQ | 20.7 ± 19.8 | 21.3 ± 21.2 | .652 |
| 6MWD, m | 449.4 ± 111.1 | 444.8 ± 123.0 | .500 |
| Chronic bronchitis | 225 (15.8) | 45 (12.9) | .207 |
| Bronchodilator response (baseline) | 246 (17.4) | 74 ± 21.6 | .089 |
| Bronchodilator response (ever) | 541 (38.8) | 158 (45.8) | .021 |
| Asthma (baseline) | 234 (16.4) | 58 (16.6) | .989 |
| Asthma (ever) | 297 (20.8) | 81 (23.2) | .367 |
| Oral steroids (baseline) | 23 (1.6) | 4 (1.1) | .693 |
| Inhaled steroids (baseline) | 273 (19.1) | 43 (12.3) | .004 |
| Inhaled bronchodilator (baseline) | 443 (31.1) | 82 (23.5) | .007 |
| Respiratory exacerbation (year prior to enrollment) | 0.29 ± 0.8 | 0.26 ± 0.8 | .583 |
| Respiratory hospitalization (yes/no, year prior to enrollment) | 107 (7.5) | 27 (7.7) | .972 |
| Ever-PRISm (phase 1 to phase 3) | 159 (11.2) | 197 (56.4) | < .001 |
| Change in BMI (phase 1 to phase 2) | −0.1 ± 2.8 | −0.2 ± 3.7 | .755 |
| Change in BMI (phase 2 to phase 3) | 0.4 ± 2.8 | 0.6 ± 2.7 | .343 |
| Change smoking status (phase 1 to phase 2) | 195 (13.7) | 60 (17.2) | .110 |
| Change smoking status (phase 2 to phase 3) | 117 (8.2) | 30 (8.6) | .897 |
| Change in pectoralis muscle area (phase 1 to phase 2) | −2.1 ± 7.4 | −2.6 ± 8.7 | .564 |
| Ever congestive heart failure | 66 (4.6) | 12 (3.4) | .409 |
| Ever chronic kidney disease | 67 (4.7) | 15 (4.3) | .859 |
Data are presented as No. (%) or mean ± SD. Lung function categories were defined as follows: PRISm (FEV1/FVC ≥ 0.7 and FEV1 < 80%), obstructed (FEV1/FVC < 0.7), and GOLD grade 0 (FEV1/FVC ≥ 0.7 and FEV1 ≥ 80%). SGRQ = St. George's Respiratory Questionnaire; 6MWD = 6-min walk distance; Asthma (baseline) = self-reported physician-diagnosed asthma at enrollment; Asthma (ever) = affirmative responses to asthma either at baseline, phase 2 or phase 3 visits; Significant transition = change in lung function category plus > 10% change in FEV1 % predicted or FVC % predicted between consecutive study visits (phase 1 to phase 2 or phase 2 to phase 3).
n = 1,670.
n = 1,489.
n = 1,597.