Table 1. Patient Baseline Characteristics by Index Hospitalization Period.
| Characteristic | Time interval, No. (%) | ||||
|---|---|---|---|---|---|
| 1995-1999 | 2000-2004 | 2005-2009 | 2010-2014 | 2015-2019 | |
| Demographic characteristics | |||||
| Patients, No. | 975 387 | 966 755 | 758 299 | 654 365 | 627 460 |
| Age, mean (SD), y | 77.4 (7.0) | 78.2 (7.2) | 78.5 (7.6) | 78.3 (7.8) | 77.4 (7.7) |
| Sex | |||||
| Female | 485 727 (49.8) | 490 924 (50.8) | 380 104 (50.1) | 314 602 (48.1) | 281 093 (44.8) |
| Male | 489 660 (50.2) | 475 831 (49.2) | 378 195 (49.9) | 339 763 (51.9) | 346 367 (55.2) |
| Race and ethnicity | |||||
| American Indian and Alaska Native | 832 (0.1) | 2342 (0.2) | 3420 (0.5) | 3461 (0.5) | 4266 (0.7) |
| Asian | 3745 (0.4) | 6923 (0.7) | 7908 (1.0) | 8841 (1.4) | 9592 (1.5) |
| Black | 60 217 (6.2) | 66 708 (6.9) | 55 326 (7.3) | 51 099 (7.8) | 47 175 (7.5) |
| Hispanic | 9658 (1.0) | 16 800 (1.7) | 12 637 (1.7) | 10 762 (1.6) | 9501 (1.6) |
| White | 884 688 (90.7) | 858 236 (88.8) | 667 198 (88.0) | 569 273 (87.0) | 540 434 (86.1) |
| Other or unreported race | 16 247 (1.7) | 15 746 (1.6) | 11 810 (1.6) | 10 929 (1.7) | 16 492 (2.6) |
| Dual Medicare-Medicaid–eligible | 134 593 (13.8) | 154 725 (16.0) | 127 354 (16.8) | 111 988 (17.1) | 95 159 (15.2) |
| Not enrolled in Medicare Part B | 5574 (0.6) | 16 047 (1.7) | 17 028 (2.2) | 21 518 (3.3) | 28 182 (4.5) |
| Living in a health priority area | 203 828 (20.9) | 199 346 (20.6) | 160 190 (21.1) | 140 333 (21.4) | 132 437 (21.1) |
| Living in an area with income <25th percentile of national average | 97 341 (10.0) | 95 233 (9.9) | 72 609 (9.6) | 62 970 (9.6) | 59 765 (9.5) |
| Admission characteristics | |||||
| From a skilled nursing facility or intermediate care facility | 6272 (0.6) | 6768 (0.7) | 6435 (0.8) | 11 035 (1.7) | 7142 (1.1) |
| From an emergency department | 634 747 (65.1) | 694 318 (71.8) | 542 757 (71.6) | 496 968 (75.9) | 475 076 (75.7) |
| Emergent or urgent admission | 827 941 (84.9) | 902 875 (93.4) | 711 475 (93.8) | 617 343 (94.3) | 597 762 (95.3) |
| Anterior MI | 193 228 (19.8) | 129 083 (13.4) | 78 562 (10.4) | 53 696 (8.2) | 37 369 (6.0) |
| Inferior, lateral, or posterior MI | 255 263 (26.2) | 174 611 (18.1) | 109 302 (14.4) | 82 574 (12.6) | 75 644 (12.1) |
| Rural hospital | 136 220 (14.0) | 129 254 (13.4) | 91 961 (12.1) | 74 666 (11.4) | 68 172 (10.9) |
| Large teaching hospital | 140 400 (14.4) | 162 910 (16.9) | 138 996 (18.3) | 110 917 (17.0) | 101 640 (16.2) |
| Private, not-for-profit hospital | 646 948 (66.3) | 686 147 (71.0) | 565 772 (74.6) | 485 693 (74.2) | 464 940 (74.1) |
| CABG-capable hospital | 479 623 (49.2) | 543 794 (56.2) | 482 144 (63.6) | 438 228 (67.0) | 415 433 (66.2) |
| Comorbidities | |||||
| Prior heart failure | 109 750 (11.3) | 115 595 (12.0) | 90 165 (11.9) | 73 077 (11.2) | 66 126 (10.5) |
| Prior MI | 31 370 (3.2) | 14 160 (1.5) | 12 954 (1.7) | 13 077 (2.0) | 12 344 (2.0) |
| Unstable angina | 49 507 (5.1) | 38 659 (4.0) | 20 263 (2.7) | 14 009 (2.1) | 15 552 (2.5) |
| Atherosclerotic disease | 645 186 (66.1) | 647 012 (66.9) | 530 174 (69.9) | 471 143 (72.0) | 395 444 (63.0) |
| Respiratory failure | 16 383 (1.7) | 16 787 (1.7) | 23 467 (3.1) | 29 002 (4.4) | 36 209 (5.8) |
| Hypertension | 478 499 (49.1) | 555 736 (57.5) | 435 077 (57.4) | 364 470 (55.7) | 296 659 (47.3) |
| Prior stroke | 16 399 (1.7) | 17 174 (1.8) | 12 790 (1.7) | 10 797 (1.6) | 9503 (1.5) |
| Cerebral vascular disease other than stroke | 40 068 (4.1) | 53 249 (5.5) | 37 210 (4.9) | 31 502 (4.8) | 22 263 (3.5) |
| Kidney failure | 38 133 (3.9) | 81 554 (8.4) | 145 166 (19.1) | 165 112 (25.2) | 178 123 (28.4) |
| COPD | 194 634 (20.0) | 212 184 (21.9) | 165 604 (21.8) | 126 879 (19.4) | 112 931 (18.0) |
| Pneumonia | 81 835 (8.4) | 110 296 (11.4) | 100 411 (13.2) | 85 658 (13.1) | 70 098 (11.2) |
| Protein-calorie malnutrition | 11 216 (1.1) | 18 632 (1.9) | 22 661 (3.0) | 28 347 (4.3) | 29 866 (4.8) |
| Dementia | 51 540 (5.3) | 80 943 (8.4) | 72 149 (9.5) | 67360 (10.3) | 57 282 (9.1) |
| Functional disability | 14 394 (1.5) | 17 564 (1.8) | 12 686 (1.7) | 11 827 (1.8) | 13 384 (2.1) |
| Peripheral vascular disease | 49 528 (5.1) | 72 352 (7.5) | 60 208 (7.9) | 51 355 (7.8) | 40 265 (6.4) |
| Cancer | 31 111 (3.2) | 53 288 (5.5) | 44 146 (5.8) | 37 323 (5.7) | 34 505 (5.5) |
| Trauma in past year | 37 519 (3.8) | 50 746 (5.2) | 45 120 (6.0) | 34 533 (5.3) | 27 460 (4.4) |
| Other major psychiatric disorders | 12 962 (1.3) | 16 632 (1.7) | 13 233 (1.7) | 13 494 (2.1) | 10 389 (1.7) |
| Liver disease | 7758 (0.8) | 18 050 (1.9) | 16 011 (2.1) | 15 185 (2.3) | 16 158 (2.6) |
| Depression | 25 004 (2.6) | 45 589 (4.7) | 39 943 (5.3) | 37 885 (5.8) | 36 157 (5.8) |
| Diabetes | 299 804 (30.7) | 287 373 (29.7) | 228 447 (30.1) | 214 482 (32.8) | 222 404 (35.4) |
| Asthma | 15 351 (1.6) | 20 775 (2.1) | 18 315 (2.4) | 16 713 (2.6) | 21 766 (3.5) |
| Anemia | 137 095 (14.1) | 199 373 (20.6) | 169 179 (22.3) | 163 757 (25.0) | 148 184 (23.6) |
| Parkinson or Huntington disease | 11 163 (1.1) | 15 244 (1.6) | 10 954 (1.4) | 9096 (1.4) | 9021 (1.4) |
| In-hospital care | |||||
| Underwent PCI or CABG | 218 120 (22.4) | 307 898 (31.8) | 314 406 (41.5) | 309 962 (47.4) | 257 922 (41.1) |
| More than 1 complicationa | 51 965 (5.3) | 47 886 (5.0) | 41 075 (5.4) | 32 668 (5.0) | 23 032 (3.7) |
| Length of stay, mean (SD), d | 7 (6.5) | 6 (6.6) | 6 (6.1) | 5 (5.2) | 5 (5.1) |
| Discharged to home | 500 269 (51.3) | 471971 (48.8) | 374 554 (49.4) | 344 808 (52.7) | 348 714 (55.6) |
| Transferred to another acute care hospital | 202 751 (20.8) | 181 658 (18.8) | 95 480 (12.6) | 60 543 (9.3) | 53 557 (8.5) |
Abbreviations: CABG, coronary artery bypass grafting; COPD, chronic obstructive pulmonary disease; MI, myocardial infarction; PCI, percutaneous coronary intervention.
a
Complications were identified using Clinical Classifications Software (CCS) and included infections (CCS-2 to CCS-10, CCS-126, CCS-135, CCS-159); complications of devices, procedures, and medical care (CSS-237 and CCS-238); and injury/contusion (CCS-239) (eTable 1 in the Supplement).