Table 1.
Subject characteristics
| Dropped out after visit 1 (n=30) | Analysis sample (available for followup; n=176) | P valuea | Among analysis sample: Physical activity level at baseline |
|||
|---|---|---|---|---|---|---|
| Active 72.7% (n=128) | Inactive 27.3% (n=48) | P valueb | ||||
| Age, y, mean (SD) | 64.5 (6.4) | 65.8 (6.0) | .30 | 65.6 (5.8) | 66.4 (6.6) | .39 |
| Female, % (n) | 40.0 (12) | 64.2 (113) | .01 | 60.2 (77) | 75.0 (36) | .07 |
| Education ≤high school, % (n) | 80.0 (24) | 77.8 (137) | .79 | 80.5 (103) | 70.8 (34) | .17 |
| Self-reported physician diagnosed, % (n) | .57 | .10 | ||||
| COPD or emphysema | 53.3 (16) | 43.9 (79) | 38.3 (49) | 56.3 (27) | ||
| Chronic bronchitis alone | 30.0 (9) | 32.2 (58) | 35.2 (45) | 25.0 (12) | ||
| Asthma without COPD or CM | 16.7 (5) | 23.9 (43) | 26.6 (34) | 18.8 (9) | ||
| Nonrespiratory comorbid conditions, % (n) | .45 | .04 | ||||
| 0 | 23.3 (7) | 25.0 (44) | 29.7 (38) | 12.5 (6) | ||
| 1 | 30.0 (9) | 39.8 (70) | 39.1 (50) | 41.7 (20) | ||
| 2+ | 46.7 (14) | 35.2 (62) | 31.3 (40) | 45.6 (22) | ||
| Smoking status, % (n) | .71 | .02 | ||||
| Current smoker | 20.0 (6) | 14.8 (26) | 10.2 (13) | 27.1 (13) | ||
| Former smoker | 56.7 (17) | 56.8 (100) | 59.4 (76) | 50.0 (24) | ||
| Never smoked | 23.3 (7) | 28.4 (50) | 30.5 (39) | 22.9 (11) | ||
| FEV1 % predicted, mean (SD) | 81.5 (21.3) | 85.4 (19.5) | .31 | 86.6 (18.4) | 82.4 (22.3) | .25 |
| FEV1/FVC, mean (SD) | 0.62 (0.16) | 0.65 (0.15) | .28 | 0.66 (0.14) | 0.63 (0.17) | .20 |
| VLA % affected, mean (SD) | 40.2 (32.7) | 25.6 (28.8) | .02 | 20.4 (25.7) | 39.3 (32) | .0005 |
| Physically inactive, % (n) | 33.3 (10) | 27.3 (48) | .50 | NA | NA | |
a
difference between individuals included in the analysis and those who were lost to followup, assessed by t-test or χ2 analysis
b
difference between individuals who were physically active and inactive at baseline, assessed by t-test or χ2 analysis
Abbreviations: COPD, CM, FEV1, FVC, VLA