Baseline characteristics of study participants (n=528)
| Characteristic* | MV needed (n=79) | MV not needed (n=449) | P value |
| Sociodemographic characteristics | |||
| Age (years)* | 57.18 (13.87) | 53.99 (13.81) | 0.059 |
| Age >60 years | 36 (46.57) | 163 (36.30) | 0.117 |
| Males | 51 (64.56) | 307 (68.37) | 0.503 |
| Hispanic/Latino ethnicity | 44 (55.70) | 259 (57.68) | 0.742 |
| Black/African-American race | 31 (39.24) | 155 (34.52) | 0.418 |
| Body mass index (kg/m2)* | 32.14 (7.54) | 31.21 (10.34) | 0.451 |
| Symptom onset → hospital admission (days)* | 6.42 (7.86) | 7.34 (6.94) | 0.314 |
| No of X-ray images per patient* | 1.96 (0.64) | 1.14 (0.47) | <0.001 |
| Comorbidities | |||
| Hypertension | 36 (46.75) | 170 (37.95) | 0.144 |
| Obesity | 42 (53.16) | 195 (43.43) | 0.109 |
| Diabetes | 40 (51.95) | 183 (40.85) | 0.069 |
| Coronary artery disease | 5 (6.49) | 38 (8.48) | 0.659† |
| Chronic kidney disease | 9 (11.69) | 27 (6.03) | 0.085† |
| Asthma | 3 (3.90) | 36 (8.04) | 0.246† |
| Chronic liver disease | 7 (9.09) | 23 (5.13) | 0.182† |
| Congestive heart failure | 2 (2.60) | 23 (5.13) | 0.560† |
| COPD | 4 (5.19) | 18 (4.02) | 0.548† |
| ESRD | 5 (6.49) | 16 (3.57) | 0.214† |
| HIV/AIDS | 3 (3.90) | 14 (3.13) | 0.726† |
| Atrial fibrillation | 1 (1.30) | 20 (4.46) | 0.340† |
| Ever smoker | 19 (24.05) | 87 (19.38) | 0.339 |
| Outcomes | |||
| Death | 52 (65.82) | 17 (3.79) | <0.001 |
Cells indicate the number (percentage) for categorical variables and mean (SD) for continuous variables indicated by a dagger (†).
*Cells indicate mean (SD) for the continuous variables; all other cells indicate number (percentage).
†Fisher’s exact test.
COPD, chronic obstructive pulmonary disease; ESRD, end-stage renal disease; MV, mechanical ventilation.