Table 1.
Baseline demographics, comorbidities, clinical features at presentation, treatments and outcomes of hospitalized patients with COVID-19 in the development dataset and external validation dataset. The variables used as input variables of the models are marked asb. Comparisons were performed with either X2 test or Fisher exact tests for categorical variables, and Student's t-test for continuous variables.
| Characteristics | Development dataset | External validation dataset | p value |
|---|---|---|---|
| N. | 299 | 402 | |
| Demographics | |||
| Age at diagnosis,bmean (±SD) | 68.79 (11.65) | 70.21 (13.17) | 0.1384 |
| Male sex,b% (number) | 69.57% (208) | 67.41% (271) | 0.5446 |
| Obesity,bBMI ≥ 30 kg/m2, % (number) | 19.40% (58) | 5.22% (21) | <.0001 |
| Ethnicity, white,% (number) | 99.33% (297) | 100% (402) | 0.1816 |
| Smoking,b( ≥ 10 pack/year), current or former, % (number) | 15.39% (46) | 3.48% (14) | <.0001 |
| Comorbidities | |||
| Diabetes,b% (number) | 19.39% (58) | 19.90% (80) | 0.8686 |
| HTN,b% (number) | 53.51% (160) | 46.77% (188) | 0.0773 |
| Cardiovascular Diseases,b% (number) | 28.09% (84) | 24.13% (97) | 0.2356 |
| CKD ≥ stage III,b % (number) | 36.12% (108) | 7.46% (30) | <.0001 |
| COPD,b % (number) | 6.35% (19) | 9.70 (39) | 0.1116 |
| Cancer (active or < 5 years), % (number) | 5.69% (17) | 6.22% (25) | 0.7686 |
| Previous stroke,% (number) | 3.34% (10) | 0.50% (2) | 0.0041 |
| Clinical presentation | |||
| Fever, temperature>37.5 °C,% (number) | 85.62% (256) | 98.01% (394) | <.0001 |
| Dry cough,% (number) | 51.51% (154) | NA | – |
| Dyspnea at resting,% (number) | 50.17% (150) | 96.52% (388) | <.0001 |
| Myalgias,% (number) | NA | 95.27% (383) | – |
| Gastrointestinal symptoms, % (number) | 6.02% (18) | 4.48% (18) | 0.3602 |
| Syncope/Presyncope, % (number) | 4.01% (12) | NA | – |
| Altered mental status, % (number) | 2.68% (8) | NA | – |
| Evidence of pneumonia at thoracic imaging,a % (number) | 96.66% (289) | 95.52% (384) | 0.4486 |
| PaO2/FiO2Ratio | 248.9 (73.6) | 355.6 (116.1) | <.0001 |
| Laboratory Characteristics | |||
| WBC, mean (±SD) | 7.89 (4.35) | 8.13 (4.32) | 0.4637 |
| Lymphocytes,b % of WBC, mean (±SD) | 14.75 (9.45) | 13.28 (7.73) | 0.0235 |
| PLT,b mean (±SD) | 187.000 (82.000) | 225.000 (98.000) | <.0001 |
| CRP,b mean (±SD) | 126.3 (88.58) | 122.8 (95.7) | 0.6260 |
| LDH,b median [25–75%IQR] | 395 [305.75–530] | 405 [304–524] | 0.9897 |
| AST, median [25–75%IQR] | 53 [38–75] | 50 [36–74.25] | 0.1225 |
| ALT,b median [25–75%IQR] | 32 [20–57] | 41 [27.75–62] | <.0001 |
| INR,b median [25–75%IQR] | 1.01 [0.96–1.12] | 1.04 [0.99–1.12] | 0.0018 |
| sCr,b (mg/dL), mean (±SD) | 1.26 (0.94) | 1.53 (1.13) | 0.0011 |
| Treatments | |||
| Antibiotics, % (number) | 83.28% (249) | 28.61% (115) | <.0001 |
| HCQ, % (number) | 22.75% (68) | 5.72% (23) | <.0001 |
| Lopinavir/ritonavir, % (number) | 21.07% (63) | 0% (0) | <.0001 |
| Prednisone, % (number) | 34.45% (103) | 0.75% (3) | <.0001 |
| Tocilizumab, % (number) | 4.01% (12) | 0% (0) | <.0001 |
| Outcomes | |||
| O2 therapy,b % (number) | 48.16% (144) | 35.57% (143) | 0.008 |
| NIV,c % (number) | 13.04% (39) | 19.65% (79) | 0.0207 |
| ICU with intubation,d % (number) | 10.03% (30) | 10.70% (43) | 0.7762 |
| Death, % (number) | 29.10% (87) | 39.55% (159) | 0.0041 |
Abbreviations: HTN: Blood hypertension, BMI: body mass index; Cardiovascular Disease: chronic heart failure, myocardial infarction, atrial fibrillation; CKD: chronic kidney disease, stage III correspond to estimated glomerular filtration rate <60 mL/min; COPD: Chronic obstructive pulmonary disease; WBC: White blood cells, PLT: platlets, CRP: C-reactive protein, LDH: lactic dehydrogenase, AST: aspartate aminotransferase; ALT: alanine aminotransferase; INR: international normalized ratio; sCr: serum Creatinine;; Antibiotics: oral Cefixime: 400 mg/day for ≥5 days; oral Azithromycin 500 mg/day for ≥5 days; oral Claritromicin 250 mg x 2/day for ≥5 days endovenoous Ceftriaxon 2 g/day for ≥5 days; endovenous piperacillina/tazobactam 4.5 mg x 3 or 4/day for ≥5 da; oral or endovenous Levofloxacin 500 mg/day for ≥5 days. HCQ: hydroxychloroquine, 200 mg 12 h apart for the first 2 doses, then 200 mg/day for ≥5 days; Oral Prednisolone or equivalents: range 5–25 mg/day for ≥5 days. NIV: Non-invasive ventilation; ICU: intesive care unit. SD = standard deviation.
Thoracic X-ray as a screening test, followed by CT-scan in doubtful cases.
O2 therapy: administered when saturation were ≤92% at resting in ambient air; required nasal canula or Venturi mask; NIV: required non-inviasive ventilation.
NIV: patients non-responsive to high-flow O2-therapy, requiring.
ICU with intubation: required intensive care unit hospitalization with intubation.