Table 2.
Authors; type of study | Country | Living/autopsy | No. of patients | Sex | Age, years | Comorbidities/predisposing factors | Anticoagulation | Outcome | Major findings/comments |
---|---|---|---|---|---|---|---|---|---|
Menter et al. [11]; cohort | Switzerland | Autopsy | 21 | 81% male | Mean 76 |
HTN: 100% CAD: 71%; obesity: 19% DM: 35% Smoker: 40% |
Anticoagulation: 52% |
Alveolar microthrombi: 45% Glomerular microthrombi: 16.7% |
Patients with blood group A may have a lower threshold of tolerance for COVID-19 |
Wichmann et al. [15]; prospective cohort | Germany | Autopsy | 12 | 75% male | Median 73 |
DM: 25% Obesity: 25% CAD: 50% COPD/asthma: 33% |
Anticoagulation: 91.6% |
DVT: 58% Mortality due to massive PE: 33% |
Extremely high D-dimer: 25% (> 20,000 ng/mL; normal < 500 ng/mL) Prolonged PT/aPTT: 33% |
Klok et al. [16]; prospective cohort | Netherlands |
Living, all ICU patients |
184 | 76% male | Mean 64 | Cancer: 2.7% | Prophylactic anticoagulation: 100% |
VTE: 27% Ischemic stroke: 3.7% (13% mortality) |
Predictor of thrombotic complications: Age: aHR 1.05/year (95% CI 17–37%) Prolongation of PT > 3 s or aPTT > 5 s: aHR 4.1, 95% CI 1.9–9.1 |
Helms et al. [17]; multicenter prospective cohort | France | Living, all ICU patients | 150 | 81.3% male | Mean 63 |
CAD: 48% DM: 20% Respiratory disease: 14% |
Prophylactic: 70% Therapeutic: 30% |
PE and DVT: 18.7% Ischemic stroke: 1.3% Mesenteric and limb ischemia: 0.7% each PE in COVID vs. non-COVID ARDS: 11.7% vs. 2.1% (OR 6.2, 95% CI 1.6–23.4; p < 0.008) |
Elevated D-dimer and fibrinogen (> 95%) Elevated vWF activity and factor VIII also seen Lupus anticoagulant: 87.7% |
Poissy et al. [18]; case series | France | Living, all ICU patients | 107 | 59.1% male | Median 57 | Median BMI: 30 kg/m2 |
When PE was diagnosed: prophylactic anticoagulation: 91% Therapeutic anticoagulation: 9% |
PE in COVID ICU (2020) vs. non-COVID ICU (2019): 20.6% vs. 6.1% AR: 14.4% (95% CI 6.1–22.8%) PE in COVID ICU (2020) vs. influenza ICU (2019): 20.6% vs. 7.5% AR: 13.1%, 95% CI 1.9–24.3% |
Risk factors for PE: D-dimer: SHR 1.81 (95% CI 1.03–3.16) Factor VIII activity: SHR 1.73 (95% CI 1.10–2.72) vWF Ag levels: SHR 1.69 (95% CI 1.12–2.56) |
Middeldorp et al. [19]; single-center cohort | Netherlands | Living | 74 | 66% male | Mean 61 |
Obesity: 14% Cancer: 3.5% |
Prophylactic anticoagulation: 100% |
VTE: 20% Cumulative incidence of VTE at 7, 14, and 21 days: 16% (95% CI 10–22), 33% (95% CI 23–43), and 42% (95% CI 30–54), respectively Cumulative incidence of VTE was higher in the ICU VTE associated with mortality: aHR 2.4 (95% CI 1.02–5.5) |
Risk factors for VTE: Higher WBC Count: SHR 1.9 (95% CI 1.1–3.2) Higher neutrophil-to-lymphocyte ratio: SHR 2.0 (95% CI 1.3–3.1) Higher D-dimer: SHR 1.6 (95% CI 1.2–2.1) |
Cui et al. [27]; retrospective | China | Living, all ICU patients | 81 | 46% male | Mean 59.9 |
HTN: 25% DM: 10% CAD: 12% Smoking: 43% |
Prophylactic anticoagulation: 0% | VTE: 25% (10% mortality) | Patients with VTE were older, had lower lymphocytes, longer aPTT, and higher D-dimer (all significant) |
Artifoni et al. [22]; retrospective cohort | France | Living, all non-ICU patients | 71 | 61% male | Median 64 |
HTN: 41% DM: 20% Cancer: 6% Smoking: 9% |
Prophylactic anticoagulation: 99% |
VTE: 22.5% (1.4% mortality) PE: 10% |
D-dimer, ICU admission, and need for invasive ventilation were significantly higher in patients with VTE |
Lodigiani et al. [21]; retrospective cohort | Italy | Living | 388 | 68% male | Median 66 |
HTN: 47.2% Smoking: 11.6% DM: 22.7% Obesity: 24.1% CAD: 13.9% Cancer: 6.4% |
Prophylactic anticoagulation: 100% in ICU and 75% in non-ICU |
VTE: 4.4% Ischemic stroke: 2.5% MI: 1.1%; all higher in ICU patients |
93.7% of VTE patients have elevated D-dimer ranging from 1620 to 40,905 ng/mL |
Llitjos et al. [20]; retrospective cohort | France | Living, all ICU patients | 26 | 77% male | Mean 68 |
HTN: 85% Smoking: 27% Median BMI: 30.2 kg/m2 |
Prophylactic anticoagulation: 31% Therapeutic: 69% |
VTE: 69% (12% mortality) PE: 23% VTE was significantly higher in the prophylactic anticoagulation group |
High rate of thromboembolic events in patients receiving therapeutic anticoagulation |
Nahum et al. [37]; prospective cohort | France | Living, all ICU patients | 34 | 78% male | Mean 62.2 |
HTN: 38% DM: 44% CAD: 9% COPD: 6% Cancer: 3% BMI mean: 31.4 kg/m2 |
Prophylactic anticoagulation: 100% | VTE: 79% (65% at admission and 14% more at 48 h of ICU admission) despite prophylactic anticoagulation | High levels of D-dimer, fibrinogen, and C-reactive protein are found in patients with VTE |
Ag antigen, aHR adjusted hazard ratio, aPTT activated partial thromboplastin time, AR absolute risk, ARDS acute respiratory distress syndrome, BMI body mass index, CAD coronary artery disease, CI confidence interval, COPD chronic obstructive pulmonary disease, COVID-19 coronavirus disease 2019, DM diabetes mellitus, DVT deep vein thrombosis, HTN hypertension, ICU intensive care unit, MI myocardial infarction, OR odds ratio, PE pulmonary embolism, PT prothrombin time, SHR subhazard ratio, VTE venous thromboembolism, vWF von Willebrand factor, WBC white blood cell