Characteristics of the 2377 invasively ventilated female and male patients with acute respiratory distress syndrome (ARDS)
| Females | Males | p-value# | |
| Patients | 905 (38.1) | 1472 (61.9) | |
| Patients >50 years old | 665 (37.2) | 1123 (62.8) | |
| Age years | 60.1±17.3 | 60.8±16.5 | 0.4057 |
| Height m | 1.60±0.08 | 1.73±0.08 | <0.0001 |
| BMI kg·m−2 | 28.8±9.2 | 26.8±8.4 | <0.001 |
| Chronic disease | |||
| COPD | 157 (17.3) | 315 (21.4) | 0.0162 |
| Diabetes mellitus | 195 (21.5) | 320 (21.7) | 0.9121 |
| Immuno-incompetence (all types) | 205 (22.7) | 280 (19.0) | 0.0330 |
| Chronic cardiac failure | 82 (9.1) | 142 (9.6) | 0.6349 |
| Chronic renal failure | 71 (7.8) | 153 (10.4) | 0.0389 |
| Chronic liver failure | 32 (3.5) | 71 (4.8) | 0.1344 |
| Specific risk factor for ARDS¶ | |||
| Pneumonia | 541 (59.8) | 844 (57.3) | 0.2410 |
| Nonpulmonary sepsis | 170 (18.8) | 243 (16.5) | 0.1549 |
| Aspiration of gastric contents | 116 (12.8) | 256 (17.4) | 0.0029 |
| Noncardiogenic shock | 84 (9.3) | 115 (7.8) | 0.2092 |
| Major trauma | 22 (2.4) | 85 (5.8) | 0.0001 |
| Blood transfusion | 44 (4.9) | 59 (4.0) | 0.3209 |
| Pulmonary contusion | 18 (2.0) | 62 (4.2) | 0.0035 |
| Inhalation injury | 17 (1.9) | 51 (3.5) | 0.0243 |
| Drug overdose | 14 (1.5) | 35 (2.4) | 0.1663 |
| Pulmonary vasculitis | 2 (0.2) | 7 (0.5) | 0.4966 |
| Severe burns | 4 (0.4) | 4 (0.3) | 0.4890 |
| Drowning | 0 (0.0) | 2 (0.1) | 0.5283 |
| Pancreatitis | 13 (1.4) | 37 (2.5) | 0.0756 |
| Other | 30 (3.3) | 39 (2.6) | 0.2481 |
| Risk factor for ARDS | 0.2625 | ||
| Only pulmonary risk factors | 511 (56.6) | 843 (57.3) | |
| Only nonpulmonary risk factors | 196 (21.7) | 286 (19.4) | |
| Both | 126 (13.9) | 239 (16.2) | |
| No risk factor | 72 (8.0) | 104 (7.1) | |
| Type of admission | |||
| Medical | 692 (76.5) | 1073 (72.9) | 0.0532 |
| Post-operative (elective) | 55 (6.1) | 88 (6.0) | 0.9214 |
| Surgical | 136 (15.0) | 230 (15.6) | 0.6952 |
| Trauma | 22 (2.4) | 81 (5.5) | 0.0004 |
| Clinician recognition of ARDS | |||
| At baseline | 300 (33.1) | 486 (33.0) | 0.9467 |
| During ICU stay | 592 (65.4) | 938 (63.7) | 0.4031 |
| ICU characteristics | |||
| Beds | 17.0 (11.0–24.0) | 17.0 (11.0–25.0) | 0.6169 |
| Proportion of beds in hospital | 2.5 (1.5–4.5) | 2.6 (1.5–4.4) | 0.4057 |
| Bed per physician | 5.0 (2.7–10.0) | 4.8 (2.7–9.4) | 0.3759 |
| Bed per nurse | 1.4 (1.0–2.0) | 1.4 (1.0–2.0) | 0.9712 |
| Academic | 687 (78.4) | 1083 (76.1) | 0.1897 |
Data are presented as n (%), mean±sd or median (interquartile range), unless otherwise stated. BMI: body mass index; COPD: chronic obstructive pulmonary disease; ICU: intensive care unit. #: comparison of male versus female patients; ¶: total is >100%, since patients could have more than one risk factor.