Table 1 Baseline characteristics of patients in the pre-matching cohort
All patients | Comparison of LTOC(+) and (−) cohorts | |||
|---|---|---|---|---|
LTOC(+) | LTOC(−) | P | ||
N | 444 | 102 | 342 | |
Age (year) | 66.5 ± 5.4 | 66.6 ± 5.2 | 66.5 ± 5.4 | 0.636 |
Sex (female) | 158 (35.6%) | 35 (34.3%) | 123 (36.0%) | 0.760 |
Race (not white) | 24 (5.4%) | 8 (7.8%) | 16 (4.7%) | 0.215 |
Annual income < 30,000$ | 228 (51.4%) | 53 (52%) | 175 (51.2%) | 0.888 |
% predicted FEV1 | 27.0 ± 7.1 | 25.2 ± 6.2 | 27.6 ± 7.2 | 0.004 |
FEV1 (L) | 0.89 ± 0.25 | 0.73 ± 0.20 | 0.80 ± 0.26 | 0.004 |
FEV1/FVC (%) | 31.1 ± 6.2 | 30.3 ± 6.2 | 31.4 ± 6.1 | 0.087 |
% predicted FVC | 68.2 ± 15.4 | 65.5 ± 13.7 | 69.1 ± 15.7 | 0.051 |
FVC (L) | 2.58 ± 0.82 | 2.47 ± 0.69 | 2.61 ± 8.3 | 0.200 |
Forced residual capacity (L) | 6.00 ± 1.24 | 6.01 ± 1.20 | 6.00 ± 1.25 | 0.953 |
Hemoglobin adjusted DLCO | 8.1 ± 3.1 | 7.6 ± 2.7 | 8.3 ± 3.2 | 0.057 |
Peak pulmonary artery pressure (mmHg) | 33.7 ± 6.2 | 33.1 ± 6.1 | 33.8 ± 6.2 | 0.341 |
(N = 377) | (N = 86) | (N = 291) | ||
Hemoglobin (g/dl) | 14.4 ± 1.3 | 14.2 ± 1.3 | 14.5 ± 1.3 | 0.193 |
PaO2 (mmHg) | 64.5 ± 10.0 | 63.4 ± 10.0 | 64.8 ± 10.0 | 0.224 |
PaCO2 (mmHg) | 43.0 ± 5.8 | 43.4 ± 5.7 | 42.9 ± 5.8 | 0.326 |
Area of emphysema (%) | 15.9 ± 10.1 | 14.9 ± 9.9 | 16.2 ± 10.2 | 0.299 |
(N = 404) | (N = 96) | (N = 308) | ||
Body mass index (kg/m^2) | 25.0 ± 3.5 | 24.4 ± 3.7 | 25.2 ± 3.4 | 0.051 |
Six − minute walk distance | 375 ± 94 | 340 ± 86 | 386 ± 94 | < 0.001 |
St. George Respiratory Questionnaire | 53.0 ± 13.1 | 57.5 ± 12.4 | 51.7 ± 13.0 | < 0.001 |
Shortness of Breath Questionnaire | 62.2 ± 19.0 | 68.0 ± 17.4 | 60.5 ± 19.1 | 0.001 |
Beck Depression Inventory | 9.1 ± 6.1 | 9.7 ± 5.9 | 9.0 ± 6.1 | 0.172 |
Recent emergency visit | 77 (17.3%) | 27 (26.5%) | 50 (14.6%) | 0.006 |
Recent hospital stay | 56 (12.6%) | 23 (22.5%) | 33 (9.6%) | < 0.001 |
LTOT during sleep | 290 (65.3%) | 78 (76.5%) | 212 (62.0%) | 0.007 |
LTOT on exertion | 300 (67.6%) | 82 (80.4%) | 218 (63.7%) | 0.002 |
Inhaled corticosteroids | 316 (71.2%) | 76 (74.5%) | 240 (70.2%) | 0.396 |
Long acting beta agonist | 197 (44.4%) | 46 (45.1%) | 151 (44.2%) | 0.866 |
Short acting beta agonist | 383 (86.3%) | 92 (90.2%) | 291 (85.1%) | 0.188 |
Anticholinergic agent | 347 (78.2%) | 80 (78.4%) | 267 (78.1%) | 0.938 |
Theophylline | 181 (40.8%) | 49 (48.0%) | 132 (38.6%) | 0.089 |
Diuretics | 56 (12.6%) | 19 (18.6%) | 37 (10.8%) | 0.037 |