Table 1. Baseline Patient Characteristics Stratified by Risk Analysis Index.
| Characteristic | Patient groupa | P value | ||
|---|---|---|---|---|
| Overall (N = 3058) | RAI <40 (n = 2266) | RAI ≥40 (n = 792) | ||
| Age, y | ||||
| Median (IQR) | 71 (63-79) | 70 (62-78) | 72 (64-82) | NA |
| 50-64 | 915 (29.9) | 699 (30.8) | 216 (27.3) | <.001b |
| 65-74 | 988 (32.3) | 762 (33.6) | 226 (28.5) | |
| 75-84 | 764 (25.0) | 570 (25.2) | 194 (24.5) | |
| ≥85 | 391 (12.8) | 235 (10.4) | 156 (19.7) | |
| Sex | ||||
| Women | 1349 (44.1) | 987 (43.6) | 362 (45.7) | .29 |
| Men | 1709 (55.9) | 1279 (56.4) | 430 (54.3) | |
| Race | ||||
| Black | 377 (12.3) | 217 (9.6) | 160 (20.2) | <.001 |
| White | 2117 (69.2) | 1593 (70.3) | 524 (66.2) | |
| Otherc | 95 (3.1) | 67 (3.0) | 28 (3.5) | |
| Unknown | 469 (15.3) | 389 (17.2) | 80 (10.1) | |
| Location prior to admission | ||||
| Home | 2317 (75.8) | 1777 (78.4) | 540 (68.2) | <.001 |
| Other | 741 (24.2) | 489 (21.6) | 252 (31.8) | |
| Comorbidities and characteristics | ||||
| Functional status | ||||
| Independent | 2725 (89.1) | 2253 (99.4) | 472 (59.6) | <.001 |
| Partially dependent | 266 (8.7) | 11 (0.5) | 255 (32.2) | |
| Totally dependent | 67 (2.2) | 2 (0.1) | 65 (8.2) | |
| Congestive heart failure | 244 (8.0) | 28 (1.2) | 216 (27.3) | <.001 |
| Weight loss | 130 (4.3) | 11 (0.5) | 119 (15.0) | <.001 |
| Diabetes | 418 (13.7) | 201 (8.9) | 217 (27.4) | <.001 |
| Dyspnea | 81 (2.6) | 16 (0.7) | 65 (8.2) | <.001 |
| Kidney failure | 351 (11.5) | 10 (0.4) | 341 (43.1) | <.001 |
| Cancer | 158 (5.2) | 154 (6.8) | 4 (0.5) | <.001 |
| Preoperative sepsis | ||||
| None | 2114 (69.1) | 1685 (74.4) | 429 (54.2) | <.001 |
| Sepsis | 212 (6.9) | 122 (5.4) | 90 (11.4) | |
| Septic shock | 376 (12.3) | 211 (9.3) | 165 (20.8) | |
| SIRS | 356 (11.6) | 248 (10.9) | 108 (13.6) | |
| ASA physical status | ||||
| 1 and 2 | 294 (9.6) | 278 (12.3) | 16 (2.0) | <.001 |
| 3 | 1160 (37.9) | 958 (42.3) | 202 (25.5) | |
| 4 | 1139 (37.2) | 672 (29.7) | 467 (59.0) | |
| 5 | 465 (15.2) | 358 (15.8) | 107 (13.5) | |
| Emergency surgery | 1195 (39.1) | 862 (38.0) | 333 (42.0) | .05 |
| General anesthesia | 2852 (93.3) | 2112 (93.2) | 740 (93.4) | .82 |
| Elective surgeryd | 1248 (40.9) | 1058 (46.8) | 190 (24.0) | <.001 |
| Operative Stress Scoree | ||||
| 1-2 (low) | 496 (17.1) | 359 (16.8) | 137 (17.9) | <.001 |
| 3 (moderate) | 1475 (50.8) | 1026 (48.0) | 449 (58.7) | |
| 4-5 (high) | 930 (32.1) | 751 (35.2) | 179 (23.4) | |
Abbreviations: ASA, American Society of Anesthesiologists; NA, not applicable; RAI, Risk Analysis Index; SIRS, systemic inflammatory response syndrome.
a
Frailty was measured using the revised RAI (stratified as RAI <40 and RAI ≥40 [frailty]). Unless indicated otherwise, data are expressed as No. (%) of patients.
b
Corresponds to a χ2 test, as age was analyzed by category (the database censors ages for patients aged ≥90 years).
c
Includes American Indian or Alaska Native, Asian, and Native Hawaiian or other Pacific Islander.
d
Includes 3053 for elective surgery and nonelective surgery (5 [0.2%] missing).
e
Includes 2901 for Operative Stress Score low, moderate, and high (157 [5.1%] missing).