Table 2.
Meta-analysis results of the whole studies on PE risk factors in COVID-19.
| Variables | Nstudiesa | PE, n/PE b | non-PE, n/non-PE c | WMD/OR | 95% CI | I2 (%) | P-value | Egger's |
|---|---|---|---|---|---|---|---|---|
| Demographic risk factors | ||||||||
| Age, years (WMD) | 26 | 847 | 3793 | 1.57 | -0.31−3.45 | 64.9% | 0.101 | 0.002 |
| Male, % (OR) | 26 | 627/911 | 2356/3836 | 1.49 | 1.26−1.76 | 0.0% | 0.000 | 0.606 |
| Obesity (BMI > 30%) | 11 | 123/329 | 237/706 | 1.37 | 1.03−1.82 | 0.0% | 0.033 | 0.238 |
| Comorbidities, % (OR) | ||||||||
| Previous VTE | 8 | 47/457 | 168/2160 | 1.37 | 0.96−1.95 | 0.0% | 0.079 | – |
| Chronic heart failure | 7 | 25/358 | 248/2619 | 0.85 | 0.55−1.31 | 35.3% | 0.456 | – |
| Cancer | 13 | 56/530 | 325/2430 | 0.81 | 0.59−1.10 | 32.4% | 0.175 | 0.473 |
| Diabetes | 18 | 146/578 | 746/3073 | 0.98 | 0.78−1.21 | 0.0% | 0.819 | 0.136 |
| Hypertension | 17 | 288/599 | 1615/3099 | 0.84 | 0.70−1.01 | 0.0% | 0.068 | 0.159 |
| Recent surgery | 3 | 4/126 | 10/389 | 0.97 | 0.30−3.12 | 0.0% | 0.955 | – |
| Cardiovascular disease | 12 | 58/381 | 383/2573 | 0.95 | 0.69−1.32 | 0.0% | 0.765 | 0.613 |
| COPD | 8 | 34/381 | 224/2466 | 0.91 | 0.62−1.35 | 0.0% | 0.651 | – |
| Clinical risk factors, % (OR) | ||||||||
| Mechanical ventilation | 5 | 52/119 | 61/266 | 3.34 | 1.90−5.86 | 10.8% | 0.000 | – |
| Severe parenchymal abnormalities on chest CT (> 50%) | 7 | 170/288 | 1183/1555 | 1.92 | 1.43−2.58 | 0.0% | 0.000 | – |
| ICU admission | 7 | 118/272 | 177/676 | 2.65 | 1.48−4.74 | 66.0% | 0.001 | – |
| Laboratory risk factors, (WMD) | ||||||||
| D-dimer, ug/ml (closest to the CTPA) | 10 | 274 | 634 | 6.03 | 5.14−6.92 | 38.0% | 0.000 | 0.872 |
| D-dimer, ug/ml (hospital admission) | 9 | 310 | 2089 | 2.10 | 1.10−3.10 | 73.8% | 0.000 | – |
| WBC, × 109/L (closest to the CTPA) | 5 | 216 | 457 | 1.46 | 0.77−2.15 | 0.0% | 0.000 | – |
| WBC, × 109/L (hospital admission) | 3 | 163 | 1786 | 2.10 | 1.21−3.00 | 0.0% | 0.000 | – |
| Lymphocytes, × 109/L (closest to the CTPA) | 3 | 38 | 57 | -0.09 | -0.62−0.43 | 51.6% | 0.734 | – |
| Lymphocytes, × 109/L (hospital admission) | 4 | 229 | 1907 | 0.009 | -0.09−0.10 | 0.0% | 0.855 | – |
| Fibrinogen, g/L (closest to the CTPA) | 4 | 136 | 268 | -0.10 | -0.77−0.56 | 22.1% | 0.759 | – |
| Fibrinogen, g/L (hospital admission) | 3 | 177 | 1270 | 0.27 | -0.07−0.60 | 0.0% | 0.122 | – |
Abbreviations: PE, pulmonary embolism; COVID-19, coronavirus disease 2019; WMD, weighted mean difference; OR, odds ratio; 95% CI, 95% confidence interval; VTE, venous thrombus embolism; COPD, chronic obstructive pulmonary disease; CT, computed tomography; WBC, white blood cells
a
Nstudies, number of studies
b
PE, n/PE, number of PE patients, number of PE patients with variable/number of PE patients
c
non-PE, n/non-PE, number of non-PE patients, number of non-PE patients with variable/number of non-PE patients; I2, index for the degree of heterogeneity; P value, significant at P < 0.05 and present in bold; Egger's, index for the degree of publication bias; –, not available