Table 2.
Baseline characteristics of patients in the propensity-score-matched cohort
| |
LTOC(+) |
LTOC(−) |
|
|---|---|---|---|
| 65 | 195 | P | |
| Age (year) |
66.3 ± 5.0 |
66.6 ± 5.3 |
0.295 |
| Sex (female) |
23 (35.4%) |
69 (35.4%) |
1 |
| Race (not white) |
3 (4.6%) |
10 (5.1%) |
0.870 |
| Annual income < 30,000$ |
36 (55.4%) |
100 (51.3%) |
0.566 |
| % predicted FEV1 |
26.4 ± 6.8 |
26.0 ± 6.6 |
0.461 |
| [FEV1 (L)] |
0.78 ± 0.22 |
0.76 ± 0.25 |
0.294 |
| [FEV1/FVC (%)] |
30.9 ± 5.6 |
31.0 ± 6.0 |
0.746 |
| % predicted FVC |
66.9 ± 13.8 |
66.1 ± 14.6 |
0.653 |
| [FVC (L)] |
2.53 ± 0.64 |
2.51 ± 0.78 |
0.644 |
| Forced residual capacity (L) |
6.05 ± 1.22 |
6.05 ± 1.24 |
0.986 |
| Hemoglobin adjusted DLCO |
7.8 ± 3.0 |
7.9 ± 3.0 |
0.733 |
| [Peak Pulmonary Artery Pressure (mmHg)] |
33.8 ± 6.0 |
34.0 ± 6.6 |
0.782 |
| (N = 55) |
(N = 167) |
||
| Hemoglobin (g/dl) |
14.4 ± 1.1 |
14.3 ± 1.3 |
0.676 |
| PaO2 (mmHg) |
63.3 ± 10.2 |
63.3 ± 9.8 |
0.989 |
| PaCO2 (mmHg) |
43.4 ± 5.7 |
43.7 ± 6.2 |
0.679 |
| [Area of emphysema (%)] |
13.5 ± 9.4 |
15.9 ± 9.8 |
0.085 |
| (N = 60) |
(N = 173) |
||
| Body mass index (kg/m^2) |
24.7 ± 3.6 |
24.6 ± 3.5 |
0.791 |
| Six − minute walk distance |
362 ± 79 |
366 ± 90 |
0.689 |
| St. George Respiratory Questionnaire |
53.8 ± 11.8 |
53.9 ± 13.3 |
0.892 |
| Shortness of Breath Questionnaire |
64.0 ± 16.4 |
63.8 ± 18.9 |
0.915 |
| Beck Depression Inventory |
9.0 ± 5.9 |
9.1 ± 6.3 |
0.988 |
| Recent emergency visit |
13 (20.0%) |
34 (17.4%) |
0.642 |
| Recent hospital stay |
9 (13.9%) |
24 (12.3%) |
0.747 |
| LTOT during sleep |
48 (73.8%) |
144 (73.8%) |
1 |
| LTOT on exertion |
50 (76.9%) |
155 (79.5%) |
0.661 |
| Inhaled corticosteroids |
49 (75.4%) |
140 (71.8%) |
0.574 |
| Long acting beta agonist |
31 (47.7%) |
94 (48.2%) |
0.942 |
| Short acting beta agonist |
57 (87.7%) |
167 (85.6%) |
0.678 |
| Anticholinergic agent |
49 (75.4%) |
155 (79.5%) |
0.486 |
| Theophylline |
30 (46.2%) |
91 (46.7%) |
0.943 |
| Diuretics | 11 (16.9%) | 31 (15.9%) | 0.846 |
[Parameters]: parameters that were not used in multi-variable logistic regression analysis for Cox model and propensity score matching were shown in brackets.
LTOC: long-term oral corticosteroids.
FEV1: forced expiratory volume in one second.
FVC: forced vital capacity.
DLCO: diffusing capacity of the lung for carbon monoxide.
PaO2: pressure of oxygen in artery.
PaCO2: pressure of carbon dioxide in artery.
LTOT: long term oxygen therapy.
Peak pulmonary artery pressure and area of emphysema were not evaluated for all patients due to lack of data.