Table 1.
Characteristics of patients with COVID-19 who required mechanical ventilation stratified by BMI.
| Variables | Overall | Nonobese (BMI < 25 kg/m2) | Obese (BMI ≥ 25 kg/m2) | p value | |
|---|---|---|---|---|---|
| n = 477 | Missing (%) | n = 242 | n = 235 | ||
| Age (year) | 67 (56–75) | – | 70 (63–77) | 61 (51–71) | < 0.001 |
| Male sex (%) | 374 (78.4) | – | 186 (77.9) | 188 (80.0) | 0.437 |
| BMI (kg/m2) | 25.0 (22.3–28.1) | – | 22.4 (20.7–23.7) | 28.2 (26.6–31.2) | < 0.001 |
| Coexisting disorder (%) | |||||
| Chronic pulmonary disease | 0 (0) | – | 0 (100) | 0 (100) | NA |
| Chronic kidney disease | 19 (4.00) | – | 14 (5.80) | 5 (2.10) | 0.059 |
| Congestive heart failure | 15 (3.10) | – | 11 (4.50) | 4 (1.70) | 0.113 |
| Diabetes | 133 (27.9) | – | 55 (22.7) | 78 (33.2) | 0.014 |
| CCI | 0 (0, 1) | – | 0 (0, 1) | 0 (0, 1) | 0.689 |
| Vital signs on admission | |||||
| SBP (mmHg) | 130.0 (114.0–152.0) | 0.63 | 128.0 (112.8–151.3) | 131.0 (117.0–151.0) | 0.410 |
| DBP (mmHg) | 75.0 (64.0–85.0) | 0.84 | 73.0 (62.0–83.0) | 78.0 (64.8–88.0) | 0.027 |
| Pulse rate (bpm) | 90 (76–103) | 1.1 | 86 (75–103) | 91 (78–103) | 0.136 |
| Respiratory rate (bpm) | 22 (18–26) | 10.9 | 22 (18–26) | 22 (18–27) | 0.346 |
| Glasgow coma scale | 15.0 (8.0–15.0) | 2.1 | 15.0 (7.5–15.0) | 15.0 (9.75–15.0) | 0.037 |
| Body temperature (°C) | 37.2 (36.6–38.1) | 0.42 | 37.1 (36.5–38.0) | 37.5 (36.6–38.3) | 0.008 |
| SOFA score on admission | 4 (3–7) | 21.4 | 4 (3–7) | 4 (2–7) | 0.184 |
| LD at the time of admission | |||||
| WBC count (× 103/μL) | 7.1 (5.4–10.1) | 17.2 | 7.3 (5.5–10.7) | 7.0 (5.1–9.5) | 0.333 |
| Platelet count (× 104/μL) | 19.0 (14.8–25.7) | 17.2 | 18.3 (14.6–25.6) | 19.5 (15.1–25.6) | 0.401 |
| Creatinine (mg/dL) | 0.87 (0.70–1.15) | 17.2 | 0.84 (0.69–1.14) | 0.90 (0.73–1.15) | 0.235 |
| Total bilirubin (mg/dL) | 0.60 (0.40–0.80) | 18.9 | 0.60 (0.40–0.80) | 0.60 (0.40–0.80) | 0.633 |
| CRP (mg/dL) | 11.5 (6.1–17.1) | 20.3 | 12.56 (6.84–18.52) | 10.06 (5.45–15.74) | 0.007 |
| d-Dimer (µg/mL) | 1.7 (1.0–4.8) | 24.9 | 2.2 (1.2–7.2) | 1.4 (0.9–3.3) | < 0.001 |
| Lactic acid (mmol/L) | 1.6 (1.1–6.0) | 25.6 | 1.5 (1.1–7.0) | 1.7 (1.2–5.0) | 0.391 |
| Respiratory therapy before IMV initiation (%) | |||||
| HFNC | 20 (4.19) | – | 8 (3.31) | 12 (5.11) | 0.367 |
| NPPV | 3 (0.63) | – | 1 (0.41) | 2 (0.85) | 0.619 |
| P/F ratio at time of IMV initiation | 130.5 (103.5–170.7) | 52.8 | 130.1 (95.8–168.3) | 130.5 (106.2–171.7) | 0.687 |
Data are presented as median (IQR) for continuous variables.
BMI body mass index, CCI Charlson Comorbidity Index, SBP systolic blood pressure, DBP diastolic blood pressure, SOFA score sequential organ failure assessment score, LD laboratory data, IMV invasive mechanical ventilation, WBC white blood cell count, CRP C-reactive protein, IMV invasive mechanical ventilation, HFNC high-flow nasal cannula, NPPV noninvasive positive pressure ventilation, P/F PaO2/FiO2.