Table 1.
Baseline Characteristics of Patients Who Underwent Pulmonary Resections for Lung Cancer in Sweden From 2008 Through 2017 Before and After IPTW
| Variable | Unweighted |
IPTW |
||||
|---|---|---|---|---|---|---|
| Men | Women | SMD | Mena | Womena | SMD | |
| No. of patients | 2,865 | 3,671 | … | 5,991.69 | 6,164.69 | … |
| Age, y | 67.6 ± 9.2 | 66.8 ± 9.1 | 0.090 | 67.1 ± 9.2 | 67.1 ± 9.1 | 0.008 |
| BMI, kg/m2 | 26.2 ± 4.3 | 25.9 ± 5.3 | 0.070 | 26.0 ± 4.6 | 26.0 ± 4.9 | 0.003 |
| Household composition | … | … | 0.174 | … | … | 0.029 |
| 2 adults, no children | 1,350 (47.1) | 1,482 (40.4) | … | 2,629.5 (43.9) | 2,673.9 (43.4) | … |
| 1 adult, no children | 1,019 (35.6) | 1,615 (44.0) | … | 2,359.0 (39.4) | 2,505.4 (40.6) | … |
| 1-2 adults and ≥1 child(ren) | 496 (17.3) | 574 (15.6) | … | 1,003.2 (16.7) | 985.3 (16.0) | … |
| Education, y | … | … | 0.135 | … | … | 0.021 |
| < 10 | 1,089 (38.0) | 1,162 (31.7) | … | 2,109.8 (35.2) | 2,110.3 (34.2) | … |
| 10-12 | 1,222 (42.7) | 1,700 (46.3) | … | 2,644.1 (44.1) | 2,773.7 (45.0) | … |
| > 12 | 554 (19.3) | 809 (22.0) | … | 1,237.8 (20.7) | 1,280.7 (20.8) | … |
| Household disposable income, kSEK | 343 ± 347 | 327 ± 405 | 0.040 | 333 ± 296 | 331 ± 386 | 0.006 |
| Smoking status | … | … | 0.214 | … | … | 0.042 |
| Never smoker | 409 (14.3) | 814 (22.2) | … | 1,079.4 (18.0) | 1,198.6 (19.4) | … |
| Former smoker | 1,586 (55.4) | 1,774 (48.3) | … | 3,084.0 (51.5) | 3,134.4 (50.8) | … |
| Current smoker | 818 (28.6) | 1,001 (27.3) | … | 1,717.9 (28.7) | 1,705.8 (27.7) | … |
| Unknown | 52 (1.8) | 82 (2.2) | … | 110.4 (1.8) | 125.8 (2.0) | … |
| Alcohol dependency | 228 (8.0) | 132 (3.6) | 0.188 | 348.4 (5.8) | 298.5 (4.8) | 0.043 |
| Preoperative predicted FEV1 < 80% | 1,040 (41.4) | 1,195 (36.5) | 0.101 | 2,052.0 (38.8) | 2,088.1 (38.1) | 0.013 |
| Performance status | … | … | 0.151 | … | … | 0.027 |
| 0 | 1,643 (57.5) | 2,357 (64.3) | … | 3,627.0 (60.5) | 3,803.7 (61.7) | … |
| 1 | 1,131 (39.6) | 1,247 (34.0) | … | 2,215.6 (37.0) | 2,223.0 (36.1) | … |
| 2+ | 83 (2.9) | 61 (1.7) | … | 149.0 (2.5) | 137.9 (2.2) | … |
| Hypertension | 1,116 (39.0) | 1,225 (33.4) | 0.116 | 2,148.0 (35.9) | 2,230.1 (36.2) | 0.007 |
| Ischemic heart disease | 675 (23.6) | 408 (11.1) | 0.333 | 1,032.2 (17.2) | 944.4 (15.3) | 0.052 |
| Atrial fibrillation | 329 (11.5) | 210 (5.7) | 0.207 | 531.1 (8.9) | 476.6 (7.7) | 0.041 |
| Hyperlipidemia | 430 (15.0) | 372 (10.1) | 0.147 | 746.4 (12.5) | 725.6 (11.8) | 0.021 |
| Heart failure | 210 (7.3) | 128 (3.5) | 0.171 | 324.3 (5.4) | 293.9 (4.8) | 0.029 |
| COPD | 458 (16.0) | 648 (17.7) | 0.045 | 964.6 (16.1) | 1,046.6 (17.0) | 0.024 |
| Diabetes mellitus | 507 (17.7) | 374 (10.2) | 0.218 | 852.8 (14.2) | 770.6 (12.5) | 0.051 |
| Prior stroke/TIA | 305 (10.6) | 252 (6.9) | 0.134 | 535.6 (8.9) | 492.4 (8.0) | 0.034 |
| Peripheral vascular disease | 315 (11.0) | 169 (4.6) | 0.240 | 477.9 (8.0) | 408.5 (6.6) | 0.052 |
| Chronic kidney disease | 70 (2.4) | 59 (1.6) | 0.059 | 116.0 (1.9) | 133.9 (2.2) | 0.017 |
| Preoperative radiotherapy | 95 (3.4) | 90 (2.5) | 0.053 | 170.6 (2.9) | 153.2 (2.6) | 0.023 |
| Preoperative chemotherapy | 133 (4.8) | 140 (3.9) | 0.043 | 263.0 (4.5) | 259.1 (4.3) | 0.009 |
| Preoperative PET scanning | 2,353 (88.9) | 3,007 (88.1) | 0.024 | 4,895.4 (88.4) | 5,055.9 (88.5) | 0.004 |
| Lobectomy/pneumonectomy | 2,268 (79.2) | 2,803 (76.4) | 0.068 | 4,712.3 (78.6) | 4,777.4 (77.5) | 0.028 |
| VATS | 510 (17.8) | 907 (24.7) | 0.169 | 1,219.3 (20.3) | 1,360.3 (22.1) | 0.042 |
| Extended resectionb | 135 (4.7) | 126 (3.4) | 0.065 | 264.5 (4.4) | 241.3 (3.9) | 0.025 |
| Lymph node sampling | 2,329 (84.2) | 2,926 (82.2) | 0.052 | 4,828.7 (83.1) | 4,950.2 (82.9) | 0.006 |
| Microscopic residual disease | 173 (6.0) | 169 (4.6) | 0.064 | 322.3 (5.4) | 302.8 (4.9) | 0.021 |
| Postoperative histopathologic findings | … | … | 0.316 | … | … | 0.062 |
| Squamous cell carcinoma | 638 (22.3) | 457 (12.4) | … | 1053.5 (17.6) | 976.6 (15.8) | … |
| Adenocarcinoma | 1,441 (50.3) | 2,087 (56.9) | … | 3,185.5 (53.2) | 3,364.7 (54.6) | … |
| Carcinoid | 154 (5.4) | 383 (10.4) | … | 455.5 (7.6) | 533.0 (8.6) | … |
| Other | 335 (11.7) | 390 (10.6) | … | 695.4 (11.6) | 679.9 (11.0) | … |
| Unknown | 297 (10.4) | 354 (9.6) | … | 601.8 (10.0) | 610.5 (9.9) | … |
| Stage of diseasec | … | … | 0.206 | … | … | 0.042 |
| IA | 966 (33.7) | 1595 (43.4) | … | 2,271.0 (37.9) | 2,437.8 (39.5) | … |
| IB | 655 (22.9) | 705 (19.2) | … | 1,291.2 (21.5) | 1,281.7 (20.8) | … |
| IIA | 366 (12.8) | 396 (10.8) | … | 702.2 (11.7) | 722.8 (11.7) | … |
| IIB | 319 (11.1) | 315 (8.6) | … | 611.0 (10.2) | 575.5 (9.3) | … |
| IIIA | 377 (13.2) | 440 (12.0) | … | 755.3 (12.6) | 780.2 (12.7) | … |
| IIIB+ | 182 (6.4) | 220 (6.0) | … | 361.1 (6.0) | 366.5 (5.9) | … |
Data are presented as No. (%) or mean ± SD, unless otherwise indicated. IPTW = inverse probability of treatment weighting; kSEK = 1,000 Swedish Krona; SMD = standardized mean difference; TIA = transient ischemic attack; VATS = video-assisted thoracic surgery.
a
The overall numbers of patients in each group are not necessarily integers owing to inverse probability of treatment weighting.
b
If any structure other than the lung or lymph nodes was included in the resection (eg, pericardium, diaphragm, thoracic wall).
c
Pathologic stage.