Demographic, clinical and laboratory predictors of intubation using multivariable logistic regression
| Univariate analysis (OR) | P value | Multivariate analysis (OR) | P value | |
| Age (years) | ||||
| ≤65 | 1 | 0.31 | ||
| >65 | 1.5 | |||
| BMI | ||||
| ≤30 | 0.57 | |||
| >30 | 0.79 | |||
| Smoking | ||||
| No | 1 | 0.32 | ||
| Yes | 1.52 | |||
| Race | ||||
| Non-black | 1 | 0.72 | ||
| Black | 0.87 | |||
| Comorbidities | ||||
| Heart disease | 1.48 | 0.41 | 2.59 | 0.047 |
| Lung disease | 1.79 | 0.19 | ||
| Diabetes | 0.91 | 0.83 | ||
| HTN | 2.1 | 0.07 | ||
| CKD | 2.91 | 0.01 | ||
| Haemodialysis | 1.49 | 0.57 | ||
| No comorbidity | 1 | 2.7 | 0.11 | |
| Any comorbidity | 3.51 | 0.03 | ||
| Laboratory markers | ||||
| Ferritin <400 | 1 | 0.79 | ||
| (ng/mL) ≥400 | 0.89 | |||
| D-dimer <1000 | 1 | 0.37 | ||
| (ng/mL) ≥1000 | 1.47 | |||
| AST <105 | 1 | 0.53 | ||
| (U/L) ≥105 | 1.6 | |||
| AST <180 | 1 | 0.26 | ||
| (U/L) ≥180 | 0.29 | |||
| Triglycerides <300 | 1 | 0.07 | ||
| (mg/dL) ≥300 | 4.81 | |||
| Fibrinogen >450 | 1 | 0.007 | 3.02 | 0.027 |
| (mg/dL) ≤450 | 3.53 | |||
| Abs Lymph Ct ≥1 | 1 | 0.26 | ||
| (K/mm3) <1 | 0.62 | |||
| LDH ≤350 | 1 | 0.18 | ||
| (U/L) >350 | 1.85 | |||
| CRP <6 | 1 | 0.22 | ||
| (mg/dL) ≥6 | 0.58 | |||
| Cumulative laboratory score (1 point per abnormality) | ||||
| <3 | 1 | 0.36 | ||
| ≥3 | 1.5 | |||
| SF ratio | ||||
| ≥100 | 1 | 0.05 | 2.61 | 0.04 |
| <100 | 2.3 | |||
Abs Lymph Ct, absolute lymphocyte count; ALT, alanine aminotransferase; AST, aspartate transaminase; BMI, body mass index; CKD, chronic kidney disease; CRP, C reactive protein; HTN, hypertension; LDH, lactate dehydrogenase; SF ratio, saturation to fraction ratio.