Table 1.
Baseline characteristics of the study population (n, %) *.
| Total | Postoperative Gastrointestinal Bleeding | |||||
|---|---|---|---|---|---|---|
| No | Yes | |||||
| n = 1,319,807 | n = 1,316,302 | n = 3505 | ||||
| Age (years) | ||||||
| Mean ± SD | 49.92 ± 17.18 | 49.87 ± 17.16 | 67.36 ± 15.06 | |||
| 20–29 | 160,689 | (12.18) | 160,616 | (99.95) | 73 | (0.05) |
| 30–39 | 278,136 | (21.07) | 278,004 | (99.95) | 132 | (0.05) |
| 40–49 | 238,445 | (18.07) | 238,179 | (99.89) | 266 | (0.11) |
| 50–59 | 236,871 | (17.95) | 236,367 | (99.79) | 504 | (0.21) |
| 60–69 | 188,721 | (14.30) | 188,065 | (99.65) | 656 | (0.35) |
| ≥70 | 216,945 | (16.44) | 215,071 | (99.14) | 1874 | (0.86) |
| Sex | ||||||
| Male | 523,657 | (39.68) | 521,762 | (99.64) | 1895 | (0.36) |
| Female | 796,150 | (60.32) | 794,540 | (99.80) | 1610 | (0.20) |
| Income status | ||||||
| Upper 80% | 1,081,113 | (81.91) | 1,078,490 | (99.76) | 2623 | (0.24) |
| Lower 20% | 238,694 | (18.09) | 237,812 | (99.63) | 882 | (0.37) |
| Residence | ||||||
| Urban | 596,306 | (45.18) | 594,827 | (99.75) | 1479 | (0.25) |
| Rural | 723,501 | (54.82) | 721,475 | (99.72) | 2026 | (0.28) |
| Preoperative comorbidities | ||||||
| Diabetes Mellitus | 128,576 | (9.74) | 127,499 | (99.16) | 1077 | (0.84) |
| Hypertension | 350,131 | (26.53) | 347,919 | (99.37) | 2212 | (0.63) |
| Dyslipidemia | 235,077 | (17.81) | 233,816 | (99.46) | 1261 | (0.54) |
| Chronic Liver Disease | 40,368 | (3.06) | 40,011 | (99.12) | 357 | (0.88) |
| Chronic Kidney Disease | 19,454 | (1.47) | 19,056 | (97.95) | 398 | (2.05) |
| Congestive Heart Failure | 31,948 | (2.42) | 31,449 | (98.44) | 499 | (1.56) |
| Peptic Ulcer Disease | 159,385 | (12.08) | 158,373 | (99.37) | 1012 | (0.63) |
| Gastroesophageal Reflux | 260,445 | (19.73) | 259,259 | (99.54) | 1186 | (0.46) |
| Preoperative drug use | ||||||
| Antiplatelet User | 186,437 | (14.13) | 185,282 | (99.38) | 1155 | (0.62) |
| Anticoagulant User | 42,744 | (3.24) | 42,341 | (99.06) | 403 | (0.94) |
| Postoperative analgesic use | ||||||
| Acetaminophen/NSAIDs | 759,784 | (57.57) | 758,047 | (99.77) | 1737 | (0.23) |
| Cyclooxygenase 2 inhibitor | 51,709 | (3.92) | 51,370 | (99.34) | 339 | (0.66) |
| Anticonvulsant | 37,161 | (2.82) | 36,971 | (99.49) | 190 | (0.51) |
| Antidepressant | 18,847 | (1.43) | 18,753 | (99.50) | 94 | (0.50) |
| Opioid | 425,756 | (32.26) | 423,488 | (99.47) | 2268 | (0.53) |
| Steroid | 188,512 | (14.28) | 187,633 | (99.53) | 879 | (0.47) |
| Postoperative gastrointestinal medication use | ||||||
| Mucosal Protective Agents | 324,242 | (24.57) | 322,659 | (99.51) | 1583 | (0.49) |
| H2 Receptor Antagonist | 416,323 | (31.54) | 414,982 | (99.68) | 1341 | (0.32) |
| Proton Pump Inhibitor | 105,806 | (8.02) | 104,538 | (98.80) | 1268 | (1.20) |
| Antacid | 364,288 | (27.60) | 362,989 | (99.64) | 1299 | (0.36) |
* p values for each characteristic are below 0.001 (t-test for continuous variables and chi-square test for categorical variables).