TABLE 2.
Overall and stratified summary statistics of included admissions
| Overall | No pDDIs | pDDIs | Discouraged drug pairs | |
|---|---|---|---|---|
| Admissions | 2 886 227 | 1 050 057 (36%) | 1 836 170 (64%) | 27 605 (1%) |
| Women | 1 551 131 (54%) | 565 697 (54%) | 985 434 (54%) | 12 655 (46%) |
| Patients | 945 475 | 553 612 | 659 525 | 18 192 |
| No. prescriptions | 9 (5–15) | 5 (3–8) | 12 (7–19) | 22 (14–36) |
| In women | 8 (4–15) | 4 (3–7) | 12 (7–19) | 22 (14–35) |
| No. unique prescribed drugs | 7 (4–11) | 4 (2–6) | 9 (6–13) | 16 (11–22) |
| Unique prescribed drugs | ||||
| 2–4 drugs | 888 934 (31%) | 629 786 (60%) | 259 148 (14%) | 520 (2%) |
| 5–9 drugs | 1 042 023 (36%) | 347 943 (33%) | 694 080 (38%) | 4408 (16%) |
| ≥ 10 drugs | 955 270 (33%) | 72 328 (7%) | 882 942 (48%) | 22 677 (82%) |
| Age in years | 62 (41–74) | 51 (30–69) | 65 (49–77) | 68 (58–77) |
| Age group | ||||
| < 18 years | 203 125 (7%) | 148 043 (14%) | 55 082 (3%) | 492 (2%) |
| 18–44 years | 619 540 (22%) | 293 005 (28%) | 326 535 (18%) | 2359 (9%) |
| 45–64 years | 773 558 (27%) | 269 693 (26%) | 503 865 (27%) | 7790 (28%) |
| 65–74 years | 577 389 (20%) | 162 494 (16%) | 414 895 (23%) | 8166 (30%) |
| 75–84 years | 461 247 (16%) | 114 094 (11%) | 347 153 (19%) | 6588 (24%) |
| ≥ 85 years | 251 368 (9%) | 62 728 (6%) | 188 640 (10%) | 2210 (8%) |
| pDDIs per patient | 1 (0–3) | 0 (0–0) | 2 (1–5) | 9 (5–15) |
| Length of stay in days | 3 (1–6) | 2 (1–4) | 3 (2–7) | 7 (3–15) |
| Acute admission | 2 107 774 (73%) | 765 816 (73%) | 1 341 958 (73%) | 19 746 (72%) |
| In‐hospital mortality | 62 830 (2%) | 14 397 (1%) | 48 433 (3%) | 1252 (5%) |
| Low eGFR (<30 mL/min/1.73m2) | 109 907 (4%) | 15 198 (1%) | 94 709 (5%) | 2660 (10%) |
| Elixhauser index (AHQR) | ||||
| <0 | 646 561 (22%) | 230 311 (22%) | 416 250 (23%) | 4893 (18%) |
| 0 | 854 868 (30%) | 399 526 (38%) | 455 342 (25%) | 3838 (14%) |
| 1–4 | 297 174 (10%) | 104 072 (10%) | 193 102 (11%) | 3157 (11%) |
| ≥5 | 1 087 624 (40%) | 316 148 (30%) | 771 476 (42%) | 15 717 (57%) |
| Most common drug classes (ATC level 3) | ||||
| Other analgesics and antipyretics (N02B) | 1 334 677 (63%) | 501 208 (48%) | 1 334 677 (73%) | 22 024 (80%) |
| Antithrombotic agents (B01A) | 1 038 880 (43%) | 211 944 (20%) | 1 038 880 (57%) | 21 890 (79%) |
| Opioids (N02A) | 917 092 (43%) | 318 180 (30%) | 917 092 (50%) | 18 098 (66%) |
| Anti‐inflammatory and antirheumatic products, non‐steroids (M01A) | 663 518 (29%) | 178 152 (17%) | 663 518 (36%) | 14 900 (54%) |
| Drugs for peptic ulcer and gastro‐oesophageal reflux disease (GORD) (A02B) | 642 650 (27%) | 141 344 (13%) | 642 650 (35%) | 15 429 (56%) |
| Beta‐lactam antibacterials, penicillins (J01C) | 686 899 (24%) | 206 305 (20%) | 480 594 (26%) | 10 796 (39%) |
| Loop (high‐ceiling) diuretics (C03C) | 518 342 (18%) | 52 487 (5%) | 465 855 (25%) | 131,98 (48%) |
| Most common primary diagnosis | ||||
| Abdominal and pelvic pain (R10) | 63 574 (2%) | 26 387 (3%) | 37 187 (2%) | 448 (2%) |
| Pneumonia, organism unspecified (J18) | 60 237 (2%) | 21 369 (2%) | 38 868 (2%) | 1057 (4%) |
| Atrial fibrillation and flutter (I48) | 55 405 (2%) | 14 422 (1%) | 40 983 (2%) | 667 (2%) |
| Mental and behavioural disorders due to use of alcohol (F10) | 51 347 (2%) | 29 206 (3%) | 22 141 (1%) | 135 (0%) |
| Other chronic obstructive pulmonary disease (J44) | 45 919 (2%) | 16 039 (2%) | 29 880 (2%) | 474 (2%) |
| Nonrheumatic aortic valve disorders (I35) | 10 244 (0%) | 1784 (0%) | 8646 (0%) | 1439 (5%) |
| Acute myocardial infarction (I21) | 30 250 (1%) | 983 (0%) | 29 267 (2%) | 244 (1%) |
| Angina pectoris (I20) | 31 664 (1%) | 5366 (1%) | 26 298 (1%) | 190 (1%) |
| Bacterial pneumonia, NOC (J15) | 24 045 (1%) | 8420 (1%) | 15 625 (1%) | 528 (2%) |
| Other sepsis (A41) | 28 401 (1%) | 7348 (1%) | 21 053 (1%) | 482 (2%) |
Note: Values are N (%) and median (interquartile range).
Abbreviations: AHRQ, Agency for Healthcare Research Quality; pDDI, potential drug–drug interaction.