Table 2.
Demographic and clinical characteristics of patients with respiratory virus infections in intensive care units.
| Total n = 335 | Cases without pneumonia n = 34 (10.1%) | Cases with pneumonia | P-value* | ||||
|---|---|---|---|---|---|---|---|
| Total n = 301 (89.9%) | CAP n = 193 (64.1%) | HAP n = 108 (35.9%) | P-value | ||||
| Age (years), median (IQR) | 74 [63–82] | 74.5 [57.5–82.75] | 74 [64–82] | 74 [65–83] | 73 [63.25–81] | 0.537 | 0.952 |
| Male, n (%) | 182 (54.3) | 10 (29.4) | 172 (57.1) | 103 (53.4) | 69 (63.9) | 0.077 | 0.003 |
| Distribution of respiratory viruses | |||||||
| Influenza A virus | 93 (27.8) | 10 (29.4) | 83 (27.6) | 63 (32.6) | 20 (18.5) | 0.010 | 0.841 |
| Influenza B virus | 13 (3.9) | 1 (2.9) | 12 (4) | 10 (5.2) | 2 (1.9) | 0.223 | 1.000 |
| Rhinovirus A/B/C | 85 (25.4) | 7 (20.6) | 78 (25.9) | 48 (24.9) | 30 (27.8) | 0.586 | 0.543 |
| Common human coronavirus | 52 (15.5) | 9 (26.5) | 43 (14.3) | 22 (11.4) | 21 (19.4) | 0.061 | 0.063 |
| Respiratory syncytial virus | 44 (13.1) | 1 (2.9) | 43 (14.3) | 26 (13.5) | 17 (15.7) | 0.609 | 0.064 |
| Metapneumovirus | 24 (7.2) | 3 (8.8) | 2 (0.7) | 15 (7.8) | 6 (5.6) | 0.495 | 0.723 |
| Parainfluenza virus | 23 (6.9) | 3 (8.8) | 20 (6.6) | 10 (5.2) | 10 (9.3) | 0.227 | 0.717 |
| Human adenovirus | 17 (5.1) | 2 (5.9) | 15 (5) | 6 (3.1) | 9 (8.3) | 0.056 | 0.686 |
| Bocavirus | 3 (0.9) | 1 (2.9) | 2 (0.7) | 0 (0) | 2 (1.9) | 0.128 | 0.275 |
| Enterovirus | 2 (0.6) | 1 (2.9) | 1 (0.3) | 0 (0) | 1 (0.9) | 0.359 | 0.193 |
| Coinfection, n (%) | |||||||
| Bacterial | 151 (45.1) | 6 (17.6) | 145 (48.2) | 82 (42.5) | 63 (58.3) | 0.008 | 0.001 |
| Fungal | 4 (1.2) | 0 (0) | 4 (1.3) | 1 (0.5) | 3 (2.8) | 0.134 | 1.000 |
| Specimen, n (%) | 0.002 | ||||||
| Nasopharyngeal swab | 232 (69.3) | 32 (94.1) | 200 (66.4) | 145 (75.1) | 55 (50.9) | < 0.001 | |
| Tracheal aspirate | 67 (20) | 2 (5.9) | 65 (21.6) | 33 (17.1) | 32 (29.6) | 0.011 | |
| Bronchoalveolar lavage | 36 (10.7) | 0 (0) | 36 (12) | 15 (7.8) | 21 (19.4) | 0.003 | |
| Clinical severity on ICU admission, (mean ±SD) | |||||||
| Septic shock, n (%) | 174 (51.9) | 9 (26.5) | 165 (54.8) | 104 (53.9) | 61 (56.5) | 0.718 | 0.002 |
| APACHE-II scores | 26 [19–33] | 19 [14.5–29] | 27 [19–34] | 25 [18–34] | 28 [23–34] | 0.034 | 0.001 |
| SOFA scores | 5 [2–7] | 49.5 [39.75–62.5] | 65 [50–82] | 5 [3–7] | 5 [2–8] | 0.871 | 0.001 |
| SAPS 3 scores | 63 [48–80] | 3 [1.75–7] | 5 [2–7] | 64 [49–80] | 67 [52–83] | 0.431 | 0.038 |
| Treatment during ICU stay, n (%) | < 0.001 | ||||||
| Nasal cannula oxygen | 83 (24.8) | 23 (67.6) | 626 (20.8) | 45 (23.3) | 15 (13.9) | 0.052 | |
| Non-invasive ventilation | 70 (20.9) | 4 (11.8) | 66 (21.9) | 48 (24.9) | 18 (16.7) | 0.111 | |
| Mechanical ventilation | 174 (51.9) | 7 (20.6) | 167 (55.5) | 93 (48.2) | 74 (68.5) | 0.001 | |
| Extracorporeal membrane oxygenation | 8 (2.4) | 0 (0) | 8 (2.7) | 7 (3.6) | 1 (0.9) | 0.268 | |
| Hemodialysis | 27 (8.1) | 4 (11.8) | 66 (22.1) | 17 (32.1) | 10 (27.8) | 0.815 | 0.275 |
| Underlying conditions, n (%) | |||||||
| Charlson comorbidity score, median [IQR] | 5 [4–6] | 5 [2.75–5.25] | 5 [4–6] | 5 [4–6] | 5 [4–6] | 0.747 | 0.320 |
| Congestive heart failure | 81 (24.2) | 15 (44.1) | 66 (21.9) | 45 (23.3) | 21 (19.4) | 0.436 | 0.006 |
| Chronic lung diseases | 68 (20.3) | 4 (11.8) | 64 (21.3) | 43 (22.3) | 21 (19.4) | 0.564 | 0.261 |
| Diabetes mellitus | 98 (29.3) | 4 (11.8) | 94 (31.2) | 61 (31.6) | 33 (30.6) | 0.850 | 0.027 |
| End-stage renal diseases | 18 (5.4) | 0 (0) | 18 (6) | 8 (4.1) | 10 (9.3) | 0.081 | 0.235 |
| Liver cirrhosis | 10 (3) | 1 (2.9) | 9 (3) | 6 (3.1) | 3 (2.8) | 1.000 | 1.000 |
| Cerebrovascular disease | 47 (14) | 5 (14.7) | 42 (14) | 25 (13) | 17 (15.7) | 0.503 | 0.800 |
| Solid cancer | 44 (13.1) | 1 (2.9) | 43 (14.3) | 27 (14) | 16 (14.8) | 0.844 | 0.064 |
| Hematologic malignancy | 13 (3.9) | 0 (0) | 13 (4.3) | 6 (3.1) | 7 (6.5) | 0.236 | 0.377 |
| Solid organ transplant | 4 (1.2) | 0 (0) | 17 (5.6) | 0 (0) | 4 (3.7) | 0.016 | 1.000 |
| Recent admission | 97 (29) | 9 (26.5) | 88 (29.2) | 33 (17.1) | 55 (50.9) | < 0.001 | 0.843 |
| Receipt of chemotherapy | 17 (5.1) | 0 (0) | 17 (5.6) | 10 (5.2) | 7 (6.5) | 0.639 | 0.236 |
| Recent surgery | 8 (2.4) | 0 (0) | 8 (2.7) | 2 (1) | 6 (5.6) | 0.027 | 1.000 |
| Laboratory findings, median (IQR) | |||||||
| White blood cells, /μL | 10,500 [7,060–14,900] | 9,450 [7,165–13,627.5] | 10,620 [7,000–14,950] | 10,600 [7,200–14,350] | 10,710 [7,000–15,800] | 0.490 | 0.551 |
| Neutrophil cell count, /μL | 8148 [5303–12165] | 7323.5 [5302.75–9858.75] | 8337.5 [5283.75–12,235.75] | 7870 [5230–11,710] | 8970 [5,400–13,690] | 0.232 | 0.302 |
| Neutropenia, n (%) | 14 (4.2) | 0 (0) | 14 (4.7) | 8 (4.1) | 6 (5.6) | 0.777 | 0.376 |
| Lymphocyte count, /μL | 834 [415–1374.75] | 1120.5 [822.75–2051.75] | 807.5 [400.5–1308.75] | 820 [425–1485] | 760 [280–1600] | 0.036 | 0.003 |
| Lymphocytopenia, n (%) | 197 (58.8) | 13 (38.2) | 184 (61.1) | 111 (57.5) | 73 (68.2) | 0.083 | 0.011 |
| Platelets, × 103/μL | 176 [117–247] | 192 [135.75–221.25] | 175 [114.5–247] | 177 [123–246] | 165.50 [87.50–252] | 0.259 | 0.195 |
| Creatinine, mg/dL | 1.08 [0.79–1.59] | 1.18 [0.8125–1.7075] | 1.07 [0.775–1.59] | 1.10 [0.8–1.55] | 1.01 [0.69–1.82] | 0.367 | 0.719 |
| C-reactive protein, mg/L | 102.49[34.22–191.75] | 20.175 [5.185–102.605] | 118.14 [43.94–199.185] | 100.02 [29.61–191.68] | 133.94 [67.94–223.59] | 0.008 | < 0.001 |
| C-reactive protein ≥ 100 mg/L, n (%) | 173 (51.6) | 8 (23.5) | 165 (54.8) | 97 (50.3) | 68 (63.0) | 0.040 | < 0.001 |
| Procalcitonin, ng/mL | 0.61 [0.20–2.97] | 0.2850 [0.0830–1.67] | 0.6895 [0.2155–3.1775] | 0.54 [0.18–2.97] | 1.17 [0.36–5.11] | 0.040 | 0.039 |
| Procalcitonin ≥ 0.5 ng/mL | 162 (48.4) | 9 (26.5) | 153 (50.8) | 74 (41.1) | 49 (53.3) | 0.071 | 0.026 |
| Outcomes | |||||||
| ICU days, median (IQR) | 5 [3–9] | 3.5 [2–6] | 5 [3–9] | 4 [3–8] | 7.5 [4–12] | < 0.001 | 0.003 |
| Total hospital days, median (IQR) | 21 [12–36] | 21 [12.5–37] | 15.5 [9–33] | 17 [10–28] | 31.5 [16–52.5] | < 0.001 | 0.069 |
| Hospital days after RVIs diagnosis, median (IQR) | 16 [9–29] | 13 [7.75–24.5] | 17 [9–29.5] | 15 [9–26] | 18 [10–37.75] | 0.087 | 0.243 |
| 28-day mortality, n (%) | 64 (19.1) | 2 (5.9) | 62 (20.6) | 39 (20.2) | 23 (21.3) | 0.882 | 0.062 |
| All-cause mortality, n (%) | 103 (30.7) | 4 (11.8) | 99 (32.9) | 52 (26.9) | 47 (43.5) | 0.003 | 0.017 |
| RTI-related mortality, n (%) | 74 (22.1) | 0 (0) | 74 (24.6) | 39 (20.2) | 35 (32.4) | 0.025 | 0.001 |
CAP, community-acquired pneumonia; HAP, hospital-acquired pneumonia; IQR, interquartile range; ICU, intensive care unit; APACHE-II, Acute Physiology and Chronic Health Evaluation II; SOFA, sepsis-related organ failure assessment; RTI, respiratory tract infections; SAPS 3, Simplified Acute Physiology Score 3. P-value for the heterogeneity test between positive and negative groups in the mPCR tests.
*P-value for the Pearson's χ2 test, Fisher's exact test, or Mann–Whitney U test between cases without pneumonia and pneumonia cases.
The bold values indicate P < 0.05.