Table 1.
Baseline characteristics of patients with cancer-associated venous thrombosis before and after inverse probability of treatment weighting
| Characteristics | Unweighted | Weighted | ||||
|---|---|---|---|---|---|---|
| Non-Switchers | Switchers | SMD | Non-Switchers | Switchers | SMD | |
| N | 2656 | 1700 | 4347 | 4379 | ||
| Age (mean (SD)), year | 65.9 (13.6) | 66.8 (12.6) | 0.069 | 66.3 (13.5) | 66.2 (12.8) | 0.002 |
| Sex, Female | 1420 (53.5) | 961 (56.5) | 0.062 | 2378 (54.7) | 2407 (55.0) | 0.005 |
| Cancer sites | ||||||
| Lip oral cavity and pharynx | 50 (1.9) | 28 (1.6) | 0.018 | 77 (1.8) | 75 (1.7) | 0.004 |
| Digestive organs | 773 (29.1) | 447 (26.3) | 0.063 | 1228 (28.3) | 1241 (28.3) | 0.002 |
| Respiratory system | 553 (20.8) | 429 (25.2) | 0.105 | 969 (22.3) | 966 (22.1) | 0.006 |
| Bone skin and soft tissue | 31 (1.2) | 39 (2.3) | 0.086 | 70 (1.6) | 70 (1.6) | < 0.001 |
| Breast and genital organs | 635 (23.9) | 416 (24.5) | 0.013 | 1045 (24.1) | 1049 (23.9) | 0.002 |
| Urinary organs | 125 (4.7) | 60 (3.5) | 0.059 | 184 (4.2) | 179 (4.1) | 0.007 |
| Eye brain and other central nervous system endocrine glands | 35 (1.3) | 21 (1.2) | 0.007 | 55 (1.3) | 57 (1.3) | 0.002 |
| Lymphatic and hematopoietic tissue | 115 (4.3) | 73 (4.3) | 0.002 | 187 (4.3) | 188 (4.3) | < 0.001 |
| Metastasis | 1128 (42.5) | 691 (40.6) | 0.037 | 1813 (41.7) | 1810 (41.3) | 0.008 |
| Comorbidities | ||||||
| Obesity | 53 (2.0) | 68 (4.0) | 0.118 | 121 (2.8) | 122 (2.8) | < 0.001 |
| Tobacco use disorder | 16 (0.6) | 21 (1.2) | 0.066 | 32 (0.7) | 34 (0.8) | 0.004 |
| Alcohol use disorder | 30 (1.1) | 20 (1.2) | 0.004 | 50 (1.1) | 52 (1.2) | 0.003 |
| Other drug abuse disorder | 14 (0.5) | 7 (0.4) | 0.017 | 22 (0.5) | 24 (0.5) | 0.006 |
| Diabetes | 391 (14.7) | 315 (18.5) | 0.102 | 699 (16.1) | 701 (16.0) | 0.002 |
| Hypertension | 688 (25.9) | 559 (32.9) | 0.154 | 1241 (28.6) | 1252 (28.6) | 0.001 |
| Hyperlipidemia | 242 (9.1) | 278 (16.4) | 0.219 | 512 (11.8) | 514 (11.7) | 0.001 |
| Atrial fibrillation | 80 (3.0) | 52 (3.1) | 0.003 | 134 (3.1) | 133 (3.0) | 0.002 |
| Congestive heart failure | 109 (4.1) | 61 (3.6) | 0.027 | 168 (3.9) | 172 (3.9) | 0.003 |
| Vascular disease | 172 (6.5) | 110 (6.5) | <0.001 | 283 (6.5) | 288 (6.6) | 0.002 |
| Renal disease | 171 (6.4) | 81 (4.8) | 0.073 | 255 (5.9) | 270 (6.2) | 0.013 |
| Medications in the last three months | ||||||
| Cancer-related treatment | ||||||
| Drug therapy | 1035 (39.0) | 837 (49.2) | 0.208 | 1867 (42.9) | 1864 (42.6) | 0.007 |
| Radiotherapy | 171 (6.4) | 69 (4.1) | 0.107 | 241 (5.5) | 244 (5.6) | 0.001 |
| Aspirin | 447 (16.8) | 246 (14.5) | 0.065 | 699 (16.1) | 723 (16.5) | 0.012 |
| Antiplatelet (except Aspirin) | 65 (2.4) | 33 (1.9) | 0.035 | 100 (2.3) | 105 (2.4) | 0.007 |
| NSAIDs (except Aspirin) | 522 (19.7) | 283 (16.6) | 0.078 | 805 (18.5) | 822 (18.8) | 0.006 |
| Erythropoietin | 10 (0.4) | 4 (0.2) | 0.026 | 13 (0.3) | 12 (0.3) | 0.006 |
| EGFR inhibitors | 171 (6.4) | 150 (8.8) | 0.090 | 321 (7.4) | 325 (7.4) | 0.002 |
| VEGF/VEGF receptor inhibitors | 67 (2.5) | 45 (2.6) | 0.008 | 113 (2.6) | 111 (2.5) | 0.003 |
| CYP3A4/P-glycoprotein inducers/inhibitors | 299 (11.3) | 169 (9.9) | 0.043 | 469 (10.8) | 479 (10.9) | 0.005 |
| SSRIs/SNRIs | 84 (3.2) | 75 (4.4) | 0.065 | 156 (3.6) | 151 (3.4) | 0.008 |
| Khorana Risk Score | 0.164 | 0.002 | ||||
| Low (< 2) | 1049 (39.5) | 809 (47.6) | 1854 (42.7) | 1864 (42.6) | ||
| High (>=2) | 1607 (60.5) | 891 (52.4) | 2493 (57.3) | 2515 (57.4) | ||
| CCI | 0.039 | 0.010 | ||||
| Low (< 6) | 1108 (41.7) | 677 (39.8) | 1786 (41.1) | 1821 (41.6) | ||
| High (> = 6) | 1548 (58.3) | 1023 (60.2) | 2561 (58.9) | 2558 (58.4) | ||
| History of central venous catheter surgery | 74 (2.8) | 73 (4.3) | 0.082 | 148 (3.4) | 148 (3.4) | 0.001 |
| Surgery in the last three months | 1146 (43.1) | 646 (38.0) | 0.105 | 1803 (41.5) | 1827 (41.7) | 0.005 |
| Blood transfusion in the last three months | 164 (6.2) | 75 (4.4) | 0.079 | 240 (5.5) | 252 (5.8) | 0.010 |
| Hospitalization attendance in the last three months (mean (SD)) | 3.1 (2.3) | 3.0 (2.4) | 0.051 | 3.0 (2.3) | 3.1 (2.5) | 0.004 |
| A&E attendance in the last three months (mean (SD)) | 1.5 (1.2) | 1.3 (1.2) | 0.133 | 1.4 (1.2) | 1.4 (1.2) | 0.001 |
N Number of patients, SMD Standardized mean difference, SD Standard deviation, NSAIDs Non-steroidal anti-inflammatory drugs, EGFR Epidermal growth factor receptor, VEGF Vascular endothelial growth factors, CYP3A4 cytochrome P450 3A4, SSRIs/SNRIs Selective serotonin reuptake inhibitors/serotonin and norepinephrine reuptake inhibitors, CCI Charlson comorbidity index, A&E: Accident and emergency.