Table 1.
Demographic and clinical characteristics of the study sample
| Characteristic | ARDS patients | Controls | p value | |
|---|---|---|---|---|
| (n = 321) | (n = 871) | |||
| Sex (% male) | 63.2 | 59.6 | 0.242a | |
| Median age, yr (P25–P75) | 67 (55–75) | 41 (32–49) | <0.001b | |
| Hypertension (%) | 42.4 | 3.1 | <0.001a | |
| Smoker (%) | 27.9 | 31.2 | 0.422a | |
| Previous surgery (%) | 65 | NA | ||
| Ischemic cardiac disease (%) | 9.0 | NA | ||
| Source of sepsis (%) | ||||
| Pulmonary | 41.9 | NA | ||
| Extrapulmonary | 58.1 | NA | ||
| Pathogen (%) | ||||
| Gram-negative | 29.3 | NA | ||
| Gram-positive | 21.1 | NA | ||
| Mixed | 5.7 | NA | ||
| Polymicrobial | 3.3 | NA | ||
| Virus | 2.8 | NA | ||
| Fungi | 2.8 | NA | ||
| Negative blood cultures | 35.0 | NA | ||
| Organ dysfunction (%) | ||||
| Circulatory | 58.0 | NA | ||
| Renal | 43.6 | NA | ||
| Hepatic | 21.4 | NA | ||
| Neurologic | 20.8 | NA | ||
| Coagulation | 18.9 | NA | ||
| APACHE II, mean (P25–P75) | 22 (17–27) | NA | ||
| PaO2/FiO2 mean,c mmHg (P25–P75) | 206 (124–255) | |||
| ICU mortality (%) | 36.3 | NA | ||
APACHE II Acute Physiology and Chronic Health Evaluation II, ICU intensive care unit, NA not applicable, P 25 percentile 25, P 75 percentile 75, PaO 2 /FiO 2 ratio of partial pressure arterial oxygen and fraction of inspired oxygen
aχ2 test
bMann–Whitney U test
cAt the time of onset