Table 1.
Baseline Characteristics for Final Study Populations Used for Primary and Secondary Analysis: 2001–2017 Nationwide Hospitalizations in IBM MarketScan Research Databasea
| Characteristic | Primary Case/Control Definitions (LOS >3 d) |
Secondary Analysis | |||
|---|---|---|---|---|---|
| HO-CDI Cases (Secondary CDI) | No CDI | All Secondary CDI Cases | Any CDI Case | No CDI Controls | |
| No. of patients | 70 760 (100) | 6 890 780 (100) | 84 683 (100) | 135 461 (100) | 17 205 857 (100) |
| Age, y | |||||
| 18–26 | 2241 (3.17) | 478 965 (6.95) | 3013 (3.56) | 5094 (3.76) | 1 668 118 (9.7) |
| 27–44 | 6391 (9.03) | 1 301 627 (18.89) | 8456 (9.99) | 14 796 (10.92) | 5 258 516 (30.56) |
| 45–64 | 29 046 (41.05) | 2 569 394 (37.29) | 34 587 (40.84) | 55 104 (40.68) | 6 137 416 (35.67) |
| ≥65 | 33 082 (46.75) | 2 540 794 (36.87) | 38 627 (45.61) | 60 467 (44.64) | 4 141 807 (24.07) |
| Female sex | 38 469 (54.37) | 3 931 557 (57.06) | 46 828 (55.3) | 80 205 (59.21) | 11 086 895 (64.44) |
| Length of stay, d | |||||
| 1–3 | … | … | 14 066 (16.61) | 34 858 (25.73) | 11 902 198 (69.18) |
| 4–6 | 18 707 (26.44) | 4 329 780 (62.83) | 18 652 (22.03) | 35 882 (26.49) | 3 335 259 (19.38) |
| 7–9 | 13 882 (19.62) | 1 271 083 (18.45) | 13 842 (16.35) | 20 360 (15.03) | 969 607 (5.64) |
| 10–12 | 8907 (12.59) | 498 691 (7.24) | 8889 (10.5) | 11 540 (8.52) | 382 302 (2.22) |
| 13–15 | 6596 (9.32) | 276 068 (4.01) | 6590 (7.78) | 7945 (5.87) | 212 810 (1.24) |
| >15 | 22 668 (32.04) | 515 158 (7.48) | 22 644 (26.74) | 24 876 (18.36) | 403 681 (2.35) |
| Exposures within 180 d of hospitalization | |||||
| Prior hospitalization | 38 317 (54.15) | 1 475 433 (21.41) | 44 177 (52.17) | 64 705 (47.77) | 1 805 205 (10.49) |
| Prior nursing home/LTC visit | 13 200 (18.65) | 285 438 (4.14) | 15 079 (17.81) | 21 199 (15.65) | 354 003 (2.06) |
| Prior ED visit | 23 370 (33.03) | 1 609 488 (23.36) | 28 289 (33.41) | 46 020 (33.97) | 3 326 621 (19.33) |
| Prior ambulatory surgery | 5715 (8.08) | 455 667 (6.61) | 6907 (8.16) | 11 707 (8.64) | 960 698 (5.58) |
| Other prior outpatient visit | 68 137 (96.29) | 6 468 856 (93.88) | 81 653 (96.42) | 131 107 (96.79) | 16 215 109 (94.24) |
| Prior family member with CDI | 121 (0.17) | 3492 (0.05) | 144 (0.17) | 276 (0.2) | 7016 (0.04) |
| Low-risk antibiotic use | 17 082 (24.14) | 1 265 832 (18.37) | 20 876 (24.65) | 34 638 (25.57) | 2 717 009 (15.79) |
| High-risk antibiotic use | 27 504 (38.87) | 1 787 244 (25.94) | 33 672 (39.76) | 75 710 (55.89) | 3 694 760 (21.47) |
| No. of comorbidities | |||||
| 0 | 6638 (9.38) | 1 383 724 (20.08) | 8876 (10.48) | 16 663 (12.3) | 6 279 682 (36.5) |
| 1 | 14 442 (20.41) | 1 809 495 (26.26) | 18 012 (21.27) | 31 848 (23.51) | 4 501 401 (26.16) |
| 2 | 17 420 (24.62) | 1 571 702 (22.81) | 20 627 (24.36) | 32 501 (23.99) | 3 156 292 (18.34) |
| 3 | 15 520 (21.93) | 1 098 163 (15.94) | 18 080 (21.35) | 26 811 (19.79) | 1 835 343 (10.67) |
| 4 | 10 026 (14.17) | 628 427 (9.12) | 11 507 (13.59) | 16 798 (12.4) | 917 555 (5.33) |
| 5 | 4669 (6.6) | 280 488 (4.07) | 5319 (6.28) | 7735 (5.71) | 371 667 (2.16) |
| 6 | 1610 (2.28) | 92 634 (1.34) | 1767 (2.09) | 2454 (1.81) | 114 138 (0.66) |
| 7 | 380 (0.54) | 22 139 (0.32) | 431 (0.51) | 557 (0.41) | 25 364 (0.15) |
| ≥8 | 55 (0.08) | 4008 (0.06) | 64 (0.08) | 94 (0.07) | 4415 (0.03) |
Data are presented as No. (%).
Abbreviations: ED, emergency department; HO-CDI, hospital-onset Clostridioides difficile infection; LTC, long-term care; LOS, length of stay.
aSimilar counts corresponding to all hospitalizations (ie, not restricted to 1 hospitalization per enrollee) can be found in Supplementary Table 2.