Table 2

Clinical characteristics and outcomes of patients with COVID-19 by BMI groups

CharacteristicBMI groups^P#
Normal (n = 845)Underweight (n = 75)Overweight (n = 572)Obesity (n = 145)
COVID-19 severity, n (%)0.577
 Mild7 (0.8)2 (2.7)4 (0.7)1 (0.7)
 Moderate581 (68.8)48 (64.0)385 (67.3)91 (62.8)
 Severe243 (28.8)25 (33.3)176 (30.8)50 (34.5)
 Critical14 (1.7)0 (0.0)7 (1.2)3 (2.1)
Outcomes
 Death3 (0.4)1 (1.3)2 (0.3)2 (1.4)0.261
 Discharge764 (90.4)68 (90.7)509 (89.0)133 (91.7)0.721
 Transfer1 (0.1)2 (2.7)1 (0.2)0 (0.0)<0.001
Length of hospital stays, median (IQR)12.00 (7.00, 19.00)11.00 (7.00, 16.50)12.00 (7.00, 17.00)11.00 (7.00, 18.50)0.548
ICU admission20 (2.4)3 (4.0)15 (2.6)4 (2.8)0.854
Length of ICU stay, median (IQR)9.00 (8.00, 14.25)3.00 (2.00, 5.00)5.00 (3.00, 9.00)6.00 (3.50, 9.00)0.039
Days from first admission to death, median (IQR)19.00 (18.00, 34.00)12.00 (12.00, 12.00)20.50 (13.75, 27.25)9.00 (6.00, 12.00)0.335
Oxygen therapy209 (24.7)17 (22.7)134 (23.4)44 (30.3)0.369
 High-flow nasal cannula oxygen therapy200 (23.7)15 (20.0)128 (22.4)42 (29.0)0.343
 Noninvasive mechanical ventilation21 (2.5)0 (0.0)17 (3.0)5 (3.4)0.434
 Invasive mechanical ventilation16 (1.9)3 (4.0)9 (1.6)4 (2.8)0.462
 Endotracheal intubation9 (1.1)2 (2.7)5 (0.9)3 (2.1)0.391
 ECMO2 (0.2)0 (0.0)1 (0.2)0 (0.0)0.910
Renal replacement therapy1 (0.1)1 (1.3)0 (0.0)0 (0.0)0.019
Complications, n (%)
 Sepsis1 (0.1)0 (0.0)0 (0.0)1 (0.7)0.202
 Respiratory failure6 (0.7)0 (0.0)7 (1.2)1 (0.7)0.611
 Heart failure8 (0.9)1 (1.3)7 (1.2)0 (0.0)0.594
 Septic shock42 (5.0)9 (12.0)23 (4.0)10 (6.9)0.021
 Coagulopathy5 (0.6)2 (2.7)2 (0.3)0 (0.0)0.060
 Acute cardiac injury4 (0.5)0 (0.0)3 (0.5)0 (0.0)0.774
 Acute kidney injury1 (0.1)1 (1.3)1 (0.2)0 (0.0)0.117
 Secondary infection22 (2.6)8 (10.7)12 (2.1)6 (4.1)<0.001
 Hypoproteinemia23 (2.7)9 (12.0)16 (2.8)5 (3.4)<0.001
 Acidosis7 (0.8)0 (0.0)3 (0.5)2 (1.4)0.608
Medication, n (%)
 Antiviral376 (44.5)35 (46.7)251 (43.9)65 (44.8)0.972
  Chloroquine43 (5.1)4 (5.3)29 (5.1)3 (2.1)0.450
  Oseltamivir83 (9.8)4 (5.3)51 (8.9)13 (9.0)0.616
  Arbidol347 (41.1)32 (42.7)236 (41.3)63 (43.4)0.952
  Ribavirin15 (1.8)1 (1.3)13 (2.3)4 (2.8)0.796
  Two of the above68 (8.0)4 (5.3)43 (7.5)12 (8.3)0.846
 Corticosteroids98 (11.6)12 (16.0)68 (11.9)19 (13.1)0.697
 Intravenous Ig198 (23.4)31 (41.3)108 (18.9)31 (21.4)<0.001
 IL-6 inhibitors26 (3.1)2 (2.7)12 (2.1)3 (2.1)0.689
 Convalescence serum59 (7.0)4 (5.3)47 (8.2)11 (7.6)0.742
 Chinese medicine (any)618 (73.1)55 (73.3)406 (71.0)93 (64.1)0.160
  • IQR, interquartile range.

  • ^ BMI categories: underweight, BMI <18.5 kg/m2; normal weight, 18.5–23.9 kg/m2; overweight, 24.0–27.9 kg/m2; and obesity, ≥28 kg/m2.

  • # P value was calculated from Kruskal-Wallis test for nonnormally distributed continuous variables or from χ2 test or Fisher exact test for categorical variables.