Table 3.
Comparison of clinical characteristics of intensive care unit (ICU) patients with pandemic influenza A (H1N1pdm09) virus by acute respiratory distress syndrome (ARDS) and death status
| Characteristics | ARDS | Death | ||||
|---|---|---|---|---|---|---|
| Yes (n = 48) | No (n = 80) | P‐value | Yes (n = 37) | No (n = 117) | P‐value | |
| Age, median (IQR),* year | 28 (21–42) | 30 (11–49) | 0·89 | 30 (21–46) | 30 (13–49) | 0·83 |
| Age ≥ 18 years, no. (%) | 38 (79) | 52 (65) | 0·09 | 28 (76) | 80 (69) | 0·40 |
| Illness onset to admission, median (IQR), day | 5 (2–6) (n = 48) | 3 (2–4) (n = 78) | <0·01 | 5 (2–6) (n = 37) | 3 (2–5) (n = 115) | 0·03 |
| Admission ≤ 2 days after illness onset, no. (%) | 16/48 (33) | 36/78 (46) | 0·16 | 10/37 (27) | 51/115 (44) | 0·06 |
| Length of hospital stay, median (IQR), day | 16 (7–24) (n = 46) | 6 (3–10) (n = 80) | <0·01 | 7 (3–14) (n = 37) | 8 (4–16) (n = 115) | 0·33 |
| ICU length of stay, median (IQR), day | 11 (5–15) (n = 35) | 2 (1–5) (n = 59) | <0·01 | 5 (2–12) (n = 36) | 3 (2–11) (n = 78) | 0·16 |
| Any medical underlying condition,** no. (%) | 27 (56) | 53 (66) | 0·26 | 25 (68) | 75 (64) | 0·70 |
| Asthma | 9 (19) | 26 (33) | 0·09 | 4 (11) | 33 (28) | 0·05 |
| Chronic obstructive pulmonary disease | 2 (4) | 9 (11) | 0·21 | 4 (11) | 14 (12) | 1·00 |
| Neurological disease | 3 (6) | 16 (20) | 0·04 | 5 (14) | 21 (18) | 0·62 |
| Obesity,*** no. (%) | ||||||
| Obese versus not obese | 9/28 (32) | 15/54 (28) | 0·24 | 9/24 (38) | 20/74 (27) | 0·21 |
| Morbidly obese versus not obese | 10/28 (36) | 10/54 (19) | 0·04 | 6/24 (25) | 15/74 (20) | 0·36 |
| Radiographic evidence of pneumonia at admission, no. (%) | 43/47 (91) | 40/72 (56) | <0·01 | 32/35 (91) | 69/107 (64) | <0·01 |
| Treatment with influenza antivirals, no. (%) | 42 (88) | 63 (79) | 0·21 | 28 (76) | 100 (85) | 0·17 |
| ≤2 days after illness onset | 7/42 (17) | 22/60 (37) | <0·01† | 2/28 (7) | 34/97 (35) | <0·01† |
| 3–5 days after illness onset | 10/42 (24) | 26/60 (43) | <0·01† | 11/28 (39) | 34/97 (35) | 0·32† |
| ≥6 days after illness onset | 25/42 (60) | 12/60 (20) | 15/28 (54) | 29/97 (30) | ||
| Sepsis syndrome, no. (%) | 22/41 (54) | 9/80 (11) | <0·01 | 21/30 (70) | 15/100 (15) | <0·01 |
| ARDS | – | – | – | 23/29 (79) | 25/99 (25) | <0·01 |
| Death, No. (%) | 23 (48) | 6 (8) | <0·01 | – | – | – |
*Interquartile range.
**Patients who are pregnant, immunocompromised (either because of medications or immune disorders including human immunodeficiency syndrome), or have chronic pulmonary (including asthma or chronic obstructive pulmonary disease), cardiovascular (excludes hypertension), renal, hepatic, hematological, neurological, or metabolic disease (including diabetes) are considered at high‐risk for influenza‐related complications.
***Obesity categories are mutually exclusive.
†Compared with ≥6 days after illness onset.