Table 1.
Clinical and demographic characteristics of the cohort stratified by extended-duration low molecular weight heparin.
| Colectomy1,4 | Oophorectomy2,4 | Hysterectomy3,4 | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| No LMWH | Extended-Duration LMWH | P-value | No LMWH | Extended-Duration LMWH | P-value | No LMWH | Extended-Duration LMWH | P-value | |||||||
| N | (%) | N | (%) | N | (%) | N | (%) | N | (%) | N | (%) | ||||
| 39,437 | (98.4) | 631 | (1.6) | 9,001 | (87.7) | 1,259 | (12.3) | 13,213 | (91.0) | 1,305 | (9.0) | ||||
| Age | <0.001 | 0.002 | 0.36 | ||||||||||||
| ≤34 | 710 | (1.8) | 22 | (3.5) | 532 | (5.9) | 47 | (3.7) | 198 | (1.5) | 25 | (1.9) | |||
| 35–44 | 2,643 | (6.7) | 50 | (7.9) | 985 | (10.9) | 114 | (9.1) | 892 | (6.8) | 79 | (6.1) | |||
| 45–54 | 9,063 | (23.0) | 199 | (31.5) | 2,446 | (27.2) | 352 | (28.0) | 2,958 | (22.4) | 290 | (22.2) | |||
| 55–64 | 13,037 | (33.1) | 223 | (35.3) | 3,250 | (36.1) | 500 | (39.7) | 6,092 | (46.1) | 627 | (48.1) | |||
| ≥65 | 13,984 | (35.5) | 137 | (21.7) | 1,788 | (19.9) | 246 | (19.5) | 3,073 | (23.3) | 284 | (21.8) | |||
| Sex | 0.04 | — | — | ||||||||||||
| Female | 19,031 | (48.3) | 330 | (52.3) | — | — | — | — | — | — | — | — | |||
| Male | 20,406 | (51.7) | 301 | (47.7) | — | — | — | — | — | — | — | — | |||
| Year | 0.52 | <0.001 | <0.001 | ||||||||||||
| 2009 | 7,024 | (17.8) | 100 | (15.9) | 1,731 | (19.2) | 109 | (8.7) | 2,618 | (19.8) | 175 | (13.4) | |||
| 2010 | 8,968 | (22.7) | 158 | (25.0) | 2,166 | (24.1) | 255 | (20.3) | 3,353 | (25.4) | 295 | (22.6) | |||
| 2011 | 9,573 | (24.3) | 152 | (24.1) | 2,144 | (23.8) | 305 | (24.2) | 3,236 | (24.5) | 334 | (25.6) | |||
| 2012 | 8,533 | (21.6) | 131 | (20.8) | 1,872 | (20.8) | 347 | (27.6) | 2,600 | (19.7) | 305 | (23.4) | |||
| 2013 | 5,339 | (13.5) | 90 | (14.3) | 1,088 | (12.1) | 243 | (19.3) | 1,406 | (10.6) | 196 | (15.0) | |||
| Region | <0.001 | <0.001 | <0.001 | ||||||||||||
| Northeast | 7,444 | (18.9) | 92 | (14.6) | 2,026 | (22.5) | 220 | (17.5) | 3,313 | (25.1) | 275 | (21.1) | |||
| North central | 10,441 | (26.5) | 206 | (32.7) | 2,063 | (22.9) | 447 | (35.5) | 3,678 | (27.8) | 560 | (42.9) | |||
| South | 14,331 | (36.3) | 233 | (36.9) | 2,928 | (32.5) | 331 | (26.3) | 3,444 | (26.1) | 251 | (19.2) | |||
| West | 6,738 | (17.1) | 88 | (14.0) | 1,870 | (20.8) | 240 | (19.1) | 2,666 | (20.2) | 197 | (15.1) | |||
| Unknown | 483 | (1.2) | 12 | (1.9) | 114 | (1.3) | 21 | (1.7) | 112 | (0.9) | 22 | (1.7) | |||
| Comorbidity 5 | <0.001 | 0.35 | 0.56 | ||||||||||||
| 0 | 26,787 | (67.9) | 476 | (75.4) | 7,219 | (80.2) | 1,030 | (81.8) | 9,340 | (70.7) | 935 | (71.7) | |||
| 1 | 8,469 | (21.5) | 123 | (19.5) | 1,341 | (14.9) | 176 | (14.0) | 2,920 | (22.1) | 286 | (21.9) | |||
| ≥2 | 4,181 | (10.6) | 32 | (5.1) | 441 | (4.9) | 53 | (4.2) | 953 | (7.2) | 84 | (6.4) | |||
| Colectomy type | 0.01 | — | — | ||||||||||||
| Open | 28,726 | (72.8) | 489 | (77.5) | — | — | — | — | — | — | — | — | |||
| Laparoscopic | 10,711 | (27.2) | 142 | (22.5) | — | — | — | — | — | — | — | — | |||
| Ooophorectomy type | — | <0.001 | — | ||||||||||||
| Cytoreduction | — | — | — | — | 5,706 | (63.4) | 998 | (79.3) | — | — | — | — | |||
| No cytoreduction | — | — | — | — | 3,295 | (36.6) | 261 | (20.7) | — | — | — | — | |||
| Hysterectomy type | — | — | <0.001 | ||||||||||||
| Abdominal | — | — | — | — | — | — | — | — | 7,630 | (57.8) | 886 | (67.9) | |||
| Laparoscopic | — | — | — | — | — | — | — | — | 3,508 | (26.6) | 262 | (20.1) | |||
| Robotic | — | — | — | — | — | — | — | — | 1,847 | (14.0) | 155 | (11.9) | |||
| Vaginal | — | — | — | — | — | — | — | — | 228 | (1.7) | 2 | (0.2) | |||
| Hospital complications | |||||||||||||||
| Transfusion | 2,231 | (5.7) | 27 | (4.3) | 0.14 | 443 | (4.9) | 59 | (4.7) | 0.72 | 301 | (2.3) | 39 | (3.0) | 0.11 |
| Hemorrhage | 535 | (1.4) | 8 | (1.3) | 0.85 | 163 | (1.8) | 15 | (1.2) | 0.11 | 198 | (1.5) | 7 | (0.5) | 0.005 |
| Composite | 2,658 | (6.7) | 34 | (5.4) | 0.18 | 587 | (6.5) | 73 | (5.8) | 0.33 | 469 | (3.6) | 44 | (3.4) | 0.74 |
511 patients who had VTE during the hospitalization were excluded (N=40,068).
196 patients who had VTE during the hospitalization were excluded (N=10,260).
122 patients who had VTE during the hospitalization were excluded (N=14,518).
Postoperative LMWH is defined as daily dose of enoxaparin ≤ 40 mg and/or dalteparin ≤ 5000 IU within 1 week after hospitalization (starting from date of discharge), and no VTE diagnosis before LMWH claims. 171, 147, and 166 patients in the colectomy, oophorectomy and hysterectomy cohort who received therapeutic LMWH (Lovenox > 40 mg and/or Fragmin > 5000 IU) and/or who had diagnosis of VTE before LMWH were grouped as no for postoperative LMWH.
Comorbidity defined as number of comorbid medical conditions as defined by the Charlson index.