Table 2.
Characteristics of patients according to the use of IFN as early (<7 days of symptoms) or late IFN use. Data are presented as median, interquartile range (IQR), No. (%). p-values are calculated by χ2, Fisher’s test, or Mann–Whitney’s U test.
| Variable | EIT (n = 46) |
LIT (n = 107) |
p-Value (EIT vs. LIT) |
|---|---|---|---|
| Female sex | 16 (35) | 33 (31) | 0.632 |
| Age | 76 (60–83) | 67 (58–77) | 0.098 |
| BMI (Kg/m2) | 28.2 (25–30.3) | 29.7 (25.7–32.8) | 0.159 |
| Hypertension | 11 (24) | 17 (16) | 0.21 |
| Diabetes | 7 (16) | 11 (10) | 0.29 |
| Obesity (BMI > 30) | 14 (31) | 43 (40) | 0.123 |
| Chronic kidney disease (eGFR < 60 mL/min/1.73 m2) | 7 (16) | 10 (9) | 0.19 |
| Days of symptoms until admission | 3 (1–5) | 8 (6–10) | <0.01 |
| Days from symptoms initiation to IFN | 5 (1–6) | 10 (8–11) | <0.01 |
| Fever at admission | 39 (85) | 73 (68) | 0.034 |
| Low SpO2 < 94% at admission | 36 (78) | 64 (60) | <0.01 |
| eGFR (MDRD) | 67 (52.2–82) | 75.4 (67.1–90.2) | 0.122 |
| eGFR < 60 mL/min/1.73 m2 | 18 (39) | 26 (24) | 0.086 |
| Lymphocyte count < 900/μL | 25 (55) | 60 (56) | 0.854 |
| NLR | 5.84 (3–12.6) | 6.42 (3–13.2) | 0.867 |
| Platelets < 150,000/μL | 13 (29) | 21 (20) | 0.197 |
| INR ≥ 1.3 | 14 (30) | 14 (13) | <0.001 |
| D-dimer levels (ng/mL) | 818 (606–1408) | 750 (426–2347) | 0.839 |
| Lactate dehydrogenase ≥ 250 U/L | 37 (80) | 89 (83) | 0.838 |
| C-reactive protein (mg/L) | 311 (101–455) | 146 (52–380) | <0.01 |
| Procalcitonin | 0.12 (0.06–0.25) | 0.08 (0.03–0.9) | 0.894 |
| Corticosteroids | 38 (83) | 94 (88) | 0.765 |
| Time on CE therapy (days) | 10 (4–16) | 13.5 (7–22) | 0.024 |
| ICU | 12 (26) | 34 (32) | 0.482 |
| Days from symptoms initiation to ICU | 9 (6–13) | 17 (11–23) | <0.01 |
| Days from admission to ICU | 4.5 (1–12) | 7 (2–14) | 0.447 |
| SAPS II at ICU admission | 37 (28–51) | 32 (26–40) | 0.288 |
| Apache II score at ICU admission | 16 (10–33) | 13 (10–18) | 0.224 |
| Mortality at day 30 | 23 (50) | 37 (35) | 0.242 |
| Composed outcome (ICU/Death) | 29 (63) | 59 (55) | 0.364 |
Abbreviations: EIT, early interferon-β treatment; LIT, late interferon-β treatment; No IT, no interferon-β treatment; BMI, body mass index; eGFR, estimated glomerular filtration rate; SpO2, peripheral capillary oxygen saturation; NLR, neutrophil-to-lymphocyte ratio; INR, international normalized ratio; CE, corticosteroids; SAPS II, Simplified Acute Physiologic Score II; APACHE II, Acute Physiology and Chronic Health Disease Classification System II; ICU, intensive care unit.