Table 1. Patient Characteristics by Frailty.
| Characteristic | Overall, Valuea | Modified Frailty Index | P Value | |||||
|---|---|---|---|---|---|---|---|---|
| Median (IQR) | P Value | No. (%)b | ||||||
| 0 | 1 | 2 | ≥3 | |||||
| Overall, No. | 236 957 | 1 (1-2) | 47 251 | 76 721 | 61 205 | 51 780 | ||
| Demographics | ||||||||
| Age, y (n = 225 960) | ||||||||
| 19-34 | 3711 (1.6) | 0 (0-0) | <.001 | 3147 (6.9) | 481 (0.7) | 71 (0.1) | 12 (0.0) | <.001 |
| 35-65 | 127 191 (56.3) | 1 (0-2) | 32 083 (70.3) | 44 428 (60.8) | 29 953 (51.6) | 20 727 (42.1) | ||
| >65 | 95 058 (42.1) | 2 (1-3) | 10 385 (22.8) | 28 149 (38.5) | 28 066 (48.3) | 28 458 (57.8) | ||
| Sex | ||||||||
| Male | 223 877 (94.5) | 1 (0-2) | <.001 | 42 436 (89.8) | 71 940 (93.8) | 58 840 (96.1) | 50 661 (97.8) | <.001 |
| Female | 13 080 (5.5) | 1 (1-2) | 4815 (10.2) | 4781 (6.2) | 2365 (3.9) | 1119 (2.2) | ||
| Race/ethnicity (n = 215 191) | ||||||||
| Black | 34 590 (16.1) | 1 (1-2) | <.001 | 6341 (13.4) | 12 273 (16.0) | 9063 (14.8) | 6913 (13.4) | <.001 |
| Hispanic | 10 185 (4.7) | 1 (1-2) | 2273 (4.8) | 3219 (4.2) | 2762 (4.5) | 1931 (3.7) | ||
| White | 155 016 (72.0) | 1 (1-2) | 30 290 (64.1) | 48 741 (63.5) | 40 009 (65.4) | 35 976 (69.5) | ||
| Other | 2306 (1.1) | 1 (0-2) | 614 (1.3) | 689 (0.9) | 582 (1.0) | 421 (0.8) | ||
| Unknown | 13 094 (6.1) | 1 (1-2) | 2380 (5.0) | 4339 (5.7) | 3519 (5.8) | 2856 (5.5) | ||
| BMI | ||||||||
| <18.5 | 7774 (3.3) | 2 (1-3) | <.001 | 1511 (3.2) | 2109 (2.8) | 1897 (3.1) | 2257 (4.4) | <.001 |
| 18.5-24.9 | 57 530 (24.3) | 1 (1-2) | 13 022 (27.6) | 17 073 (22.3) | 13 567 (22.2) | 13 868 (26.8) | ||
| >24.9 | 171 653 (72.4) | 1 (1-2) | 32 718 (69.2) | 57 539 (75.0) | 45 741 (74.7) | 35 655 (68.9) | ||
| ASA classification (n = 236 907) | ||||||||
| 1 | 1671 (0.7) | 0 (0-0) | <.001 | 1541 (3.3) | 100 (0.1) | 16 (0.0) | 14 (0.0) | <.001 |
| 2 | 41 310 (17.4) | 1 (0-1) | 19 523 (41.3) | 16 656 (21.7) | 4414 (7.2) | 717 (1.4) | ||
| 3 | 163 093 (68.8) | 2 (1-2) | 24 755 (52.4) | 54 957 (71.6) | 48 500 (79.3) | 34 881 (67.4) | ||
| 4 | 30 833 (13.0) | 3 (2-4) | 1418 (3.0) | 4996 (6.5) | 8264 (13.5) | 16 155 (31.2) | ||
| Marital status (n = 236 709) | ||||||||
| Married | 110 601 (46.7) | 1 (1-2) | <.001 | 20 362 (43.2) | 35 724 (46.6) | 29 593 (48.4) | 24 922 (48.2) | <.001 |
| Divorced | 71 893 (30.4) | 1 (1-2) | 15 295 (32.4) | 23 796 (31.0) | 18 011 (29.5) | 14 791 (28.6) | ||
| Separated | 9034 (3.8) | 1 (1-2) | 1933 (4.1) | 2887 (3.8) | 2239 (3.7) | 1975 (3.8) | ||
| Widowed | 20 563 (8.7) | 2 (1-3) | 2279 (4.8) | 6067 (7.9) | 5999 (9.8) | 6218 (12.0) | ||
| Single | 24 618 (10.4) | 1 (0-2) | 7294 (15.5) | 8179 (10.7) | 5298 (8.7) | 3847 (7.4) | ||
| Prior inpatient admission | ||||||||
| No | 166 012 (70.1) | 1 (1-2) | <.001 | 36 965 (78.2) | 58 489 (76.2) | 43 075 (70.4) | 27 483 (53.1) | <.001 |
| Yes | 70 945 (29.9) | 2 (1-3) | 10 286 (21.8) | 18 232 (23.8) | 18 130 (29.6) | 24 297 (46.9) | ||
| Prior ED use | ||||||||
| No | 148 638 (62.7) | 1 (1-2) | <.001 | 31 205 (66.0) | 51 418 (67.0) | 38 666 (63.2) | 27 349 (52.8) | <.001 |
| Yes | 88 319 (37.3) | 2 (1-3) | 16 046 (34.0) | 25 303 (33.0) | 22 539 (36.8) | 24 431 (47.2) | ||
| Index Hospital Characteristics | ||||||||
| Admission source | ||||||||
| Community | 107 968 (45.6) | 1 (1-2) | <.001 | 22 085 (46.7) | 35 096 (45.7) | 27 810 (45.4) | 22 977 (44.4) | <.001 |
| Outpatient | 121 751 (51.4) | 1 (1-2) | 24 005 (50.8) | 40 145 (52.3) | 31 893 (52.1) | 25 708 (49.7) | ||
| Transfer from other hospital | 2730 (1.2) | 2 (1-3) | 532 (1.1) | 583 (0.8) | 612 (1.0) | 1003 (1.9) | ||
| Nursing home or domiciliary | 3419 (1.4) | 3 (2-4) | 258 (0.6) | 546 (0.7) | 683 (1.1) | 1932 (3.7) | ||
| Nonveteran facility | 732 (0.3) | 1 (0-1) | 291 (0.6) | 273 (0.4) | 125 (0.2) | 43 (0.1) | ||
| Other | 357 (0.2) | 2 (1-3) | 80 (0.2) | 78 (0.1) | 82 (0.1) | 117 (0.2) | ||
| Discharge location | ||||||||
| Community | 207 401 (87.5) | 1 (1-2) | <.001 | 43 334 (91.7) | 68 606 (89.4) | 53 636 (87.6) | 41 825 (80.8) | <.001 |
| Other | 29 556 (12.5) | 2 (1-3) | 3917 (8.3) | 8115 (10.6) | 7569 (12.4) | 9955 (19.2) | ||
| Surgery classification (n = 236 937) | ||||||||
| Elective | 215 922 (91.1) | 1 (1-2) | <.001 | 42 719 (90.4) | 70 919 (92.4) | 55 995 (91.5) | 46 289 (89.4) | <.001 |
| Emergency | 21 015 (8.9) | 2 (1-3) | 4531 (9.6) | 5798 (7.6) | 5207 (8.5) | 5479 (10.6) | ||
| Operative type | ||||||||
| Abdominal general surgery | 92 808 (39.2) | 23 041 (48.8) | 30 430 (39.7) | 23 574 (38.5) | 15 763 (30.4) | |||
| Open | 64 161 (69.1) | 1 (1-2) | <.001 | 15 115 (65.7) | 20 799 (68.4) | 16 534 (70.2) | 11 648 (74.0) | <.001 |
| Laparoscopic | 28 647 (30.9) | 1 (0-2) | 7905 (34.3) | 9607 (31.6) | 7033 (29.8) | 4102 (26.0) | ||
| Vascular surgery | 42 801 (18.1) | 2027 (4.3) | 7642 (10.0) | 11 933 (19.5) | 21 199 (40.9) | |||
| Open | 35 478 (82.9) | 3 (2-4) | <.001 | 1539 (75.9) | 5809 (76.0) | 9539 (79.9) | 18 591 (87.7) | <.001 |
| Endovascular | 7323 (17.1) | 2 (1-3) | 488 (24.1) | 1833 (24.0) | 2394 (20.1) | 2608 (12.3) | ||
| Orthopedic | 101 348 (42.8) | 22 183 (47.0) | 38 649 (50.4) | 25 698 (42.0) | 14 818 (28.6) | |||
| Open | 100 025 (98.7) | 1 (1-2) | .002 | 21 858 (98.5) | 38 251 (99.0) | 25 380 (98.8) | 14 536 (98.1) | <.001 |
| Arthroscopic | 1323 (1.3) | 1 (1-2) | 325 (1.5) | 398 (1.0) | 318 (1.2) | 282 (1.9) | ||
| Operative time, mean (SD), h | 2 (1.5) | NA | NA | 2.4 (1.4) | 2.5 (1.4) | 2.5 (1.5) | 2.5 (1.7) | <.001 |
| Work relative value unit, mean (SD), U | 20 (7.4) | NA | NA | 19.4 (7.7) | 20.2 (7.2) | 19.8 (7.5) | 18.6 (7.4) | <.001 |
| Postoperative length of stay, mean (SD), d | 6 (4.5) | NA | NA | 5.1 (4.0) | 5.5 (4.3) | 5.9 (4.6) | 6.5 (5.0) | <.001 |
Abbreviations: ASA, American Society of Anesthesiologists; BMI, body mass index (calculated as weight in kilograms divided by height in meters squared); ED, emergency department; IQR, interquartile range; NA, not applicable.
a
Data are presented as number (percentage) of patients unless otherwise indicated.
b
Percentages represent the column percentages of nonmissing values.