Table 2.
Clinical characteristics of stage IV non‐small cell lung cancer patients without BMs before and after propensity score matching (n = 30,702)
| Factors | Before propensity score matching (n = 30,702) | After propensity score matching (n = 6,174) | |||||
|---|---|---|---|---|---|---|---|
| Immunotherapy, n (%) | p value | Immunotherapy, n (%) | p value | ||||
| Yes (n = 3,087) | No (n = 27,615) | Yes (n = 3,087) | No (n = 3,087) | ||||
| Age | <70 | 1,957 (63%) | 13,522 (49%) | <0.0001 | 1,957 (63%) | 1,959 (63%) | 0.9579 |
| ≥70 | 1,130 (37%) | 14,093 (51%) | 1,130 (37%) | 1,128 (37%) | |||
| Sex | male | 1,629 (53%) | 15,008 (54%) | 0.0950 | 1,629 (53%) | 1,628 (53%) | 0.9800 |
| female | 1,458 (47%) | 12,607 (46%) | 1,458 (47%) | 1,459 (47%) | |||
| Race | whites | 2,605 (84%) | 22,926 (83%) | 0.0544 | 2,605 (84%) | 2,601 (84%) | 0.8887 |
| others | 482 (16%) | 4689 (17%) | 482 (16%) | 486 (16%) | |||
| Insurance status | uninsured | 67 (2%) | 688 (2%) | 0.2748 | 67 (2%) | 48 (2%) | 0.0737 |
| insured | 3,020 (98%) | 26,927 (98%) | 3,020 (98%) | 3,039 (98%) | |||
| Institution | academic | 1,122 (36%) | 9,141 (33%) | 0.0003 | 1,122 (36%) | 1,513 (49%) | <0.0001 |
| others | 1,965 (64%) | 18,474 (67%) | 1,965 (64%) | 1,574 (51%) | |||
| Charlson‐Deyo score | 0–1 | 2,785 (90%) | 23,571 (85%) | <0.0001 | 2,785 (90%) | 2,791 (90%) | 0.7963 |
| ≥2 | 302 (10%) | 4,044 (15%) | 302 (10%) | 296 (10%) | |||
| Year of diagnosis | 2014 | 1,287 (42%) | 14,123 (51%) | <0.0001 | 1,287 (42%) | 1,600 (52%) | <0.0001 |
| 2015 | 1,800 (58%) | 13,492 (49%) | 1,800 (58%) | 1,487 (48%) | |||
| Histology | adenocarcinoma NOS | 2,325 (75%) | 14,980 (54%) | <0.0001 | 2,325 (75%) | 2,323 (75%) | 0.9530 |
| others | 762 (25%) | 12,635 (46%) | 762 (25%) | 764 (25%) | |||
| Nodal status | N0 | 722 (23%) | 7,665 (28%) | <0.0001 | 722 (23%) | 717 (23%) | 0.8804 |
| ≥N1 | 2,365 (77%) | 19,950 (72%) | 2,365 (77%) | 2,370 (77%) | |||
| Bone metastasis | yes | 1,455 (47%) | 10,639 (39%) | <0.0001 | 1,455 (47%) | 1,453 (47%) | 0.9593 |
| no | 1,632 (53%) | 16,976 (61%) | 1,632 (53%) | 1,634 (53%) | |||
| Liver metastasis | yes | 493 (16%) | 4,418 (16%) | 0.9674 | 493 (16%) | 485 (16%) | 0.7804 |
| no | 2,594 (84%) | 23,197 (84%) | 2,594 (84%) | 2,602 (84%) | |||
| Surgery for primary lesion | yes | 83 (3%) | 954 (3%) | 0.0255 | 83 (3%) | 86 (3%) | 0.8150 |
| no | 3,004 (97%) | 26,661 (97%) | 3,004 (97%) | 3,001 (97%) | |||
| Radiation | yes | 932 (30%) | 9,785 (35%) | <0.0001 | 932 (30%) | 932 (30%) | 1.0000 |
| no | 2,155 (70%) | 17,830 (65%) | 2,155 (70%) | 2,155 (70%) | |||
| Chemotherapy | yes | 2,834 (91%) | 16,907 (61%) | <0.0001 | 2,834 (91%) | 2,833 (92%) | 0.9630 |
| no | 253 (9%) | 10,708 (39%) | 253 (9%) | 254 (8%) | |||
Abbreviations: BM, brain metastasis; NOS, not otherwise specified.