Table 2. Encounter Characteristics by Antibacterial Exposure at the Duke Health System.
| Characteristic | Antimicrobial therapy, No. (%) of encounters (N = 170 294) | ||
|---|---|---|---|
| 0 d | 1-6 d | ≥7 d | |
| No. | 90 104 | 64 998 | 15 192 |
| Age, y | |||
| <1 | 11 695 (13) | 1950 (3) | 653 (4) |
| 1-17 | 5867 (7) | 3172 (5) | 977 (6) |
| 18-65 | 48 274 (54) | 34 170 (53) | 8201 (54) |
| >65 | 24 268 (27) | 25 706 (40) | 5361 (35) |
| Female sex | 51 212 (57) | 34 514 (53) | 7165 (47) |
| Hospital | |||
| Academic medical center | 52 723 (59) | 37 422 (58) | 10 729 (71) |
| Community hospital 1 | 25 382 (28) | 14 003 (22) | 2679 (18) |
| Community hospital 2 | 11 999 (13) | 13 573 (21) | 1784 (12) |
| Location | |||
| Labor ward | 8995 (10) | 2177 (3) | 178 (1) |
| Neurology ward | 2464 (3) | 2449 (4) | 385 (3) |
| Neurosurgery ward | 3952 (4) | 3856 (6) | 611 (4) |
| Surgery ward | 14 924 (17) | 17 059 (26) | 3545 (23) |
| Medical ward | 40 213 (45) | 34 119 (52) | 8923 (59) |
| Medical or surgical critical care | 4595 (5) | 5775 (9) | 3864 (25) |
| Pulmonary ward | 974 (1) | 1159 (2) | 830 (5) |
| Hematopoietic stem cell transplant ward | 270 (<1) | 527 (1) | 724 (5) |
| Length of stay, No. of days present | |||
| 1 | 8811 (10) | 2585 (4) | 0 |
| 2 | 25 637 (28) | 14 446 (22) | 18 (<1) |
| 3 | 22 003 (24) | 12 895 (20) | 192 (1) |
| 4-7 | 25 724 (29) | 24 381 (38) | 3757 (25) |
| 8-14 | 6212 (7) | 7922 (12) | 5231 (34) |
| >15 | 1717 (2) | 2769 (4) | 5994 (39) |
| Charlson Comorbidity Index category | |||
| Cerebrovascular disease | 9134 (10) | 5861 (9) | 2099 (14) |
| Peptic ulcer disease | 2268 (3) | 1560 (2) | 689 (5) |
| Hemiplegia or paraplegia | 2966 (3) | 2156 (3) | 1026 (7) |
| Diabetes without complication | 18 877 (21) | 16 188 (25) | 5003 (33) |
| Diabetes with complication | 10 434 (12) | 8634 (13) | 3111 (20) |
| Metastatic tumor | 5552 (6) | 5057 (8) | 1281 (8) |
| Malignancy | 5800 (6) | 4743 (7) | 1943 (13) |
| Peripheral vascular disease | 9229 (10) | 7867 (12) | 2739 (18) |
| Mild liver disease | 5800 (6) | 4743 (7) | 1943 (13) |
| Moderate or severe liver disease | 1548 (2) | 1783 (3) | 822 (5) |
| Kidney disease | 15 775 (18) | 13 822 (21) | 4813 (32) |
| COPD | 17 787 (20) | 16 704 (26) | 4974 (33) |
| Dementia | 3606 (4) | 3747 (6) | 994 (7) |
| AIDS | 389 (<1) | 423 (1) | 201 (1) |
| DRG MDC | |||
| Newborns or neonates | 10 400 (12) | 1423 (2) | 362 (2) |
| Pregnancy or childbirth | 10 382 (12) | 2253 (3) | 98 (1) |
| Endocrine, nutritional, or metabolic | 3500 (4) | 1429 (2) | 263 (2) |
| Nervous system | 7368 (8) | 3837 (6) | 804 (5) |
| Digestive system | 6680 (7) | 3533 (5) | 1127 (7) |
| Blood or blood-forming organs | 1626 (2) | 1005 (2) | 459 (3) |
| Kidney or urinary tract | 2242 (2) | 4010 (6) | 658 (4) |
| Respiratory system | 3363 (4) | 6268 (10) | 1793 (12) |
| Skin, subcutaneous tissue, or breast | 441 (<1) | 1532 (2) | 331 (2) |
| Musculoskeletal system | 3251 (4) | 13 277 (20) | 985 (6) |
| Infectious or parasitic disease | 581 (1) | 4139 (6) | 2880 (19) |
| Transplant | 116 (<1) | 433 (1) | 1425 (9) |
| Missing | 13 594 (15) | 9796 (15) | 2259 (15) |
Abbreviations: COPD, chronic obstructive pulmonary disease; DRG, Diagnosis Related Group; MDC, Major Diagnostic Categories.