Table 1.
Baseline characteristics and hypotension exposure in septic ICU patients
| Mortality | p value | Standardized difference | ||
|---|---|---|---|---|
| No | Yes | |||
| Number of patients | 74,555 | 2,773 | ||
| Age (years) | 64 ± 15 | 65 ± 14 | < 0.001 | 0.08 |
| Gender (male) | 40,144 (54%) | 1568 (57%) | 0.005 | 0.05 |
| Ethnicity | 0.024 | 0.07 | ||
| Caucasian (reference) | 55,745 (75%) | 2034 (73%) | ||
| African American | 8169 (11%) | 354 (13%) | ||
| Hispanic | 4205 (6%) | 140 (5%) | ||
| Native American | 1027 (1%) | 32 (1%) | ||
| Asian | 1095 (2%) | 49 (2%) | ||
| Other/Unknown | 4314 (6%) | 164 (6%) | ||
| BMI (kg/m2) | 29 ± 8 | 28 ± 8 | 0.024 | 0.04 |
| APACHE IVa score | 67 ± 22 | 95 ± 32 | < 0.001 | 1.02 |
| Admission type | < 0.001 | 0.29 | ||
| Emergency department (reference) | 43,598 (59%) | 1262 (46%) | ||
| Other ward | 23,045 (31%) | 1124 (41%) | ||
| Elective | 5631 (8%) | 212 (8%) | ||
| Other hospital | 2078 (3%) | 162 (6%) | ||
| Other/unknown | 203 (0.3%) | 13 (0.5%) | ||
| Admission year | < 0.001 | 0.15 | ||
| 2004 to 2008 | 4416 (6%) | 278 (10%) | ||
| 2009 to 2012 | 28,096 (38%) | 1023 (37%) | ||
| 2013 to 2016 (reference) | 42,043 (56%) | 1472 (53%) | ||
| Hospital bed size | < 0.001 | 0.09 | ||
| < 100 | 2360 (3%) | 91 (3%) | ||
| 100–249 | 15,063 (20%) | 533 (19%) | ||
| 250–500 | 17,786 (24%) | 599 (22%) | ||
| > 500 (reference) | 32,399 (44%) | 1324 (48%) | ||
| Unknown | 6947 (9%) | 226 (8%) | ||
| Aspirin | 8,989 (12%) | 297 (11%) | 0.035 | 0.04 |
| Diuretics | 10,421 (14%) | 399 (14%) | 0.56 | 0.01 |
| ACE inhibitors | 7634 (10%) | 248 (9%) | 0.029 | 0.04 |
| ARBs | 2722 (4%) | 83 (3%) | 0.077 | 0.04 |
| Beta blockers | 12,096 (16%) | 457 (17%) | 0.74 | 0.01 |
| Calcium channel blockers | 6150 (8%) | 234 (8%) | 0.75 | 0.01 |
| Hemoglobin (g/dL) | 0.001 | 0.08 | ||
| < 8 | 6761 (9%) | 307 (11%) | ||
| 8 ≤ Hb < 11 | 39,290 (53%) | 1469 (53%) | ||
| ≥ 11 (reference) | 27,638 (37%) | 961 (35%) | ||
| No reading available | 866 (1%) | 36 (1%) | ||
| Albumin (g/dL) | < 0.001 | 0.42 | ||
| < 2 | 6873 (9%) | 597 (22%) | ||
| 2 ≤ Alb < 3 | 30,902 (41%) | 1189 (43%) | ||
| ≥ 3 (reference) | 22,668 (30%) | 479 (17%) | ||
| No reading available | 14,112 (19%) | 508 (18%) | ||
| WBC (/μL) | < 0.001 | 0.37 | ||
| < 4000 | 4088 (6%) | 315 (11%) | ||
| 4000 ≤ WBC < 12,000 (reference) | 35,122 (47%) | 848 (31%) | ||
| ≥ 12,000 | 34,539 (46%) | 1572 (57%) | ||
| No reading available | 806 (1%) | 38 (1%) | ||
| BUN (mg/dL) | < 0.001 | 0.40 | ||
| ≤ 30 (reference) | 43,368 (58%) | 1077 (39%) | ||
| > 30 | 30,602 (41%) | 1,678 (61%) | ||
| No reading available | 585 (0.8%) | 18 (0.6%) | ||
| Lactate (mmol/L) | < 0.001 | 0.72 | ||
| < 2 (reference) | 31,324 (42%) | 664 (24%) | ||
| 2 ≤ Lac < 5 | 12,527 (17%) | 675 (24%) | ||
| ≥ 5 | 1763 (2%) | 597 (22%) | ||
| No reading available | 28,941 (39%) | 837 (30%) | ||
| Hypertension | 40,446 (54%) | 1441 (52%) | 0.019 | 0.05 |
| Diabetes | 26,053 (35%) | 844 (30%) | < 0.001 | 0.10 |
| COPD | 16,762 (23%) | 565 (20%) | 0.01 | 0.05 |
| Congestive heart failure | 13,401 (18%) | 507 (18%) | 0.696 | 0.008 |
| Peripheral vascular disease | 4334 (6%) | 171 (6%) | 0.46 | 0.02 |
| Valve disease | 2828 (4%) | 155 (6%) | < 0.001 | 0.09 |
| Pulmonary embolism | 1464 (2%) | 43 (2%) | 0.14 | 0.03 |
| Neuromuscular disease | 1008 (1%) | 21 (0.8%) | 0.009 | 0.06 |
| Hypothyroidism | 8021 (11%) | 281 (10%) | 0.311 | 0.02 |
| Liver disease | 3566 (5%) | 213 (8%) | < 0.001 | 0.12 |
| AIDS | 704 (1%) | 40 (1%) | 0.011 | 0.05 |
| Cancer | 12,173 (16%) | 610 (22%) | < 0.001 | 0.14 |
| Arthritis/Vasculitis | 1797 (2%) | 74 (3%) | 0.42 | 0.02 |
| Coagulopathy | 3902 (5%) | 131 (5%) | 0.254 | 0.02 |
| Anemia | 645 (0.9%) | 42 (2%) | 0.001 | 0.06 |
| Home oxygen | 3750 (5%) | 132 (5%) | 0.552 | 0.01 |
| Organ transplant | 1294 (2%) | 45 (2%) | 0.709 | 0.009 |
| Chronic kidney disease | 13,793 (19%) | 626 (23%) | < 0.001 | 0.10 |
| Myocardial infarction | 6335 (9%) | 225 (8%) | 0.499 | 0.01 |
| Stroke | 8788 (12%) | 264 (10%) | < 0.001 | 0.07 |
| Coronary artery disease | 8873 (12%) | 326 (12%) | 0.84 | 0.004 |
| On ventilator on the day of admission | 26,993 (36%) | 1826 (66%) | < 0.001 | 0.62 |
| Average vasopressor rate (mcg/kg/min in NEE) | 12 ± 54 | 94 ± 216 | < 0.001 | 0.52 |
| Lowest MAP 120-min (mmHg) | 62 ± 10 | 52 ± 9 | < 0.001 | 1.04 |
| Lowest SBP 120-min (mmHg) | 94 ± 14 | 78 ± 13 | < 0.001 | 1.23 |
| Lowest DBP 120-min (mmHg) | 48 ± 9 | 40 ± 9 | < 0.001 | 0.85 |
| Lowest PP 120-min (mmHg) | 35 ± 12 | 27 ± 11 | < 0.001 | 0.73 |
Categorical variables were expressed as the number (%), and continuous variables were presented as the mean ± standard deviation. Proportions of each category do not necessarily add up to 100% because of rounding. The listed variables were included in the multivariable analysis except for average vasopressor rate as it was a potential mediator on the causal pathway between exposure and outcome.
ACE angiotensin-converting enzyme, ARB angiotensin II receptor blockers, AIDS acquired immunodeficiency syndrome, APACHE Acute Physiology and Chronic Health Evaluation, BP blood pressure, BMI body mass index, BUN blood urea nitrogen, COPD chronic obstructive pulmonary disease, ICU intensive care unit, NEE norepinephrine equivalent, WBC white blood cell