Table 1.
Baseline characteristics before and after weighting in antibiotic cohort
| Variable | Unweighted Cohorta | Weighted Cohorta | ||||
|---|---|---|---|---|---|---|
| VN + CP (n = 442b) | VN + PT (n = 297b) | SMD | VN + CP (n = 369c) | VN + PT (n = 370c) | SMDd | |
| Demographics | ||||||
| Age, years, mean | 60.6 | 61.8 | 0.079 | 61.5 | 61.5 | 0.007 |
| Male sex, % | 54.3 | 56.6 | 0.046 | 55.6 | 54.8 | 0.019 |
| Race, % | ||||||
| White | 64.9 | 67 | 0.044 | 65.8 | 68.6 | 0.058 |
| Black | 28.1 | 26.3 | 0.040 | 27.6 | 25.9 | 0.037 |
| Asian | 3.6 | 4 | 0.022 | 3.6 | 3.3 | 0.015 |
| Other | 3.4 | 2.7 | 0.041 | 3.0 | 2.2 | 0.046 |
| BMI, mean | 27.6 | 27.1 | 0.063 | 27.3 | 27 | 0.035 |
| Admission characteristics | ||||||
| Admission source, % | ||||||
| ED | 55.7 | 46.5 | 0.185 | 52.1 | 50.1 | 0.038 |
| Ward | 36 | 45.5 | 0.194 | 39.9 | 41.9 | 0.041 |
| OSH | 8.4 | 8.1 | 0.011 | 8.1 | 8 | 0.007 |
| Mechanical ventilation, % | 41.9 | 45.5 | 0.073 | 44.2 | 41.5 | 0.055 |
| APACHE III, mean | 84.4 | 89.5 | 0.155 | 88 | 86.2 | 0.054 |
| MAP, mmHG, mean | 81.4 | 80.1 | 0.078 | 80.8 | 81 | 0.013 |
| Heart beats per minute, mean | 103.8 | 102.7 | 0.051 | 102.7 | 102.7 | 0.007 |
| Temperature, oF, mean | 99.1 | 98.7 | 0.239 | 98.9 | 98.9 | 0.017 |
| Respirations per minute, mean | 23.7 | 23 | 0.103 | 23.4 | 23.2 | 0.023 |
| Kidney function | ||||||
| Index creatinine, mg/dL, mean | 1.1 | 1.1 | 0.081 | 1.1 | 1.1 | 0.011 |
| Index eGFRe, ml/min, mean | 79.6 | 76.4 | 0.094 | 78.7 | 77.1 | 0.047 |
| Index GFR categories, % | ||||||
| eGFR ≥ 120 ml/min | 10.9 | 9.4 | 0.047 | 9.7 | 9.3 | 0.014 |
| eGFR 90–119 ml/min | 32.6 | 29 | 0.079 | 33.3 | 30.2 | 0.066 |
| eGFR 60–89 ml/min | 25.6 | 27.3 | 0.039 | 24.6 | 26 | 0.032 |
| eGFR 30–59 ml/min | 23.5 | 24.9 | 0.032 | 23.5 | 25.1 | 0.037 |
| eGFR < 30 ml/min | 7.5 | 9.4 | 0.071 | 8.9 | 9.4 | 0.017 |
| Infection characteristics | ||||||
| Vancomycin dosef, mg/kg, mean | 30.7 | 30.5 | 0.016 | 30.3 | 30.6 | 0.021 |
| Infection source, % | ||||||
| Pulmonary | 59.3 | 57.2 | 0.041 | 58.4 | 61.4 | 0.060 |
| Abdominal | 10 | 13.8 | 0.119 | 10.7 | 9.9 | 0.026 |
| Genitourinary | 7.7 | 7.4 | 0.011 | 8.4 | 8.6 | 0.010 |
| Blood | 7.5 | 6.4 | 0.042 | 6.9 | 6.2 | 0.026 |
| SSTI/Bone | 3.8 | 7.1 | 0.142 | 5 | 4.9 | 0.005 |
| Unclear/Unknown | 11.8 | 8.1 | 0.123 | 10.6 | 9.1 | 0.051 |
| Comorbidities | ||||||
| Heart failure, % | 14.7 | 12.8 | 0.056 | 14 | 13.4 | 0.018 |
| Diabetes mellitus, % | 26 | 31 | 0.110 | 27.5 | 27.9 | 0.012 |
| Hypertension, % | 52.3 | 52.9 | 0.012 | 52.2 | 50.8 | 0.030 |
| Chronic kidney disease, % | 12.2 | 11.8 | 0.013 | 11.8 | 13.5 | 0.052 |
| Cirrhosis, % | 5.7 | 12.1 | 0.229 | 7.4 | 7.8 | 0.015 |
| Metastatic solid cancer, % | 15.2 | 21.5 | 0.166 | 16.9 | 16.4 | 0.011 |
| Leukemia, % | 15.4 | 9.1 | 0.193 | 13.6 | 15.1 | 0.044 |
| Lymphoma, % | 11.3 | 4.4 | 0.260 | 8.4 | 7.5 | 0.033 |
| Myeloma, % | 4.5 | 2.7 | 0.098 | 3.8 | 4.1 | 0.020 |
| Solid organ transplant, % | 10.2 | 7.4 | 0.098 | 9 | 8.4 | 0.024 |
| Laboratory values | ||||||
| WBC, × 108 cells/L, mean | 10.8 | 14.1 | 0.265 | 12.5 | 12.2 | 0.027 |
| Hemoglobin, g/dL, mean | 9.9 | 9.9 | 0.033 | 9.9 | 9.8 | 0.031 |
| Platelets, × 1011 cells/L, mean | 174.3 | 204.5 | 0.217 | 187.3 | 187.6 | 0.014 |
| Albumin, g/dL, mean | 2.8 | 2.6 | 0.303 | 2.7 | 2.8 | 0.038 |
| Bicarbonate, mEq/L, mean | 23.7 | 22.8 | 0.181 | 23.5 | 23.5 | 0.011 |
| Chloride, mEq/L, mean | 104.8 | 104.8 | 0.001 | 104.9 | 104.9 | 0.009 |
| BUN, mg/dL, mean | 23.3 | 26.1 | 0.154 | 24.6 | 24.9 | 0.017 |
| Calcium, mg/dL, mean | 8.2 | 8.1 | 0.065 | 8.2 | 8.2 | 0.010 |
| Magnesium, mg/dL, mean | 1.8 | 1.8 | 0.008 | 1.8 | 1.8 | 0.022 |
| Bilirubin, mg/dL, mean | 1.4 | 2.7 | 0.319 | 1.8 | 1.8 | 0.018 |
| Lactate, mmol/L, mean | 2 | 2.3 | 0.138 | 2.1 | 2 | 0.024 |
| Medications | ||||||
| Aminoglycosides, % | 24.9 | 26.6 | 0.039 | 24.5 | 23.5 | 0.023 |
| NSAIDs, % | 6.1 | 6.4 | 0.012 | 6.5 | 6.6 | 0.007 |
| Calcineurin inhibitors, % | 9.5 | 6.4 | 0.115 | 8.6 | 9.4 | 0.031 |
| Loop diuretics, % | 9.5 | 13.1 | 0.115 | 11.3 | 11.8 | 0.016 |
| Trimethoprim/Sulfamethoxazole, % | 11.1 | 7.7 | 0.115 | 9.7 | 8.6 | 0.042 |
| Proton pump inhibitor, % | 39.1 | 43.1 | 0.080 | 40.4 | 41.5 | 0.023 |
| RAS inhibitor, % | 7.2 | 5.1 | 0.091 | 6.3 | 6.4 | 0.019 |
| Beta-blocker, % | 17 | 16.8 | 0.004 | 16.4 | 16.9 | 0.015 |
| Calcium channel blocker, % | 9.3 | 7.4 | 0.068 | 8.6 | 8.7 | 0.014 |
| Other antihypertensive, % | 9.7 | 5.7 | 0.150 | 8.4 | 8.7 | 0.020 |
| Stress-dose corticosteroid, % | 22.6 | 24.2 | 0.038 | 23.4 | 22.8 | 0.014 |
| Other steroids, % | 34.8 | 22.6 | 0.274 | 30.2 | 31.1 | 0.020 |
SMD standardized mean difference, BMI body mass index, ED emergency department, OSH outside hospital, APACHE Acute Physiology and Chronic Health Evaluation, MAP mean arterial pressure, eGFR estimated glomerular filtration rate, SSTI skin and soft tissue infection, WBC white blood cell, BUN blood urea nitrogen, NSAID nonsteroidal antiinflammatory drug, RAS renin–angiotensin system, VN + PT vancomycin + piperacillin–tazobactam, VN + CP vancomycin + cefepime
aTo facilitate comparisons of the unweighted and weighted population, the table shows means without standard deviation and percentages without counts
bActual sample size
cEffective sample size after inverse probability of treatment weighting
dOverall SMDs were obtained after weighting by taking the average of weighted SMDs calculated separately in each of the imputation datasets
eEstimated glomerular filtration rate was calculated using the CKD-Epidemiology equation
fVancomycin dose calculated from doses administered during the first 24 h after the index date