Journal of Hematology, ISSN 1927-1212 print, 1927-1220 online, Open Access
Article copyright, the authors; Journal compilation copyright, J Hematol and Elmer Press Inc
Journal website https://www.thejh.org

Original Article

Volume 11, Number 5, October 2022, pages 167-175


Incidence of Venous Thromboembolism in Hospitalized COVID-19 Patients Receiving Thromboprophylaxis

Figures

Figure 1.
Figure 1. Kaplan-Meier plot of 30-day VTE by TX or PPX group. VTE: venous thromboembolism; PPX: prophylaxis-intensity; TX: therapeutic-intensity.
Figure 2.
Figure 2. Kaplan-Meier plot of VTE by TX or PPX group with no truncation at 30 days. Fifty percent to VTE time for PPX group is 39 days vs. undefined for the TX group. VTE: venous thromboembolism; PPX: prophylaxis-intensity; TX: therapeutic-intensity.
Figure 3.
Figure 3. Kaplan-Meier plot of 30-day all-cause mortality by TX or PPX group. Fifty percent survival time for the TX group is 22 days vs. undefined for the PPX group. PPX: prophylaxis-intensity; TX: therapeutic-intensity.
Figure 4.
Figure 4. Kaplan-Meier plot of mortality by TX or PPX group with no truncation at 30 days. Median time to death for TX group is 27 days vs. undefined for the PPX group. PPX: prophylaxis-intensity; TX: therapeutic-intensity.

Tables

Table 1. Baseline Characteristics
 
Prophylactic anticoagulation (n = 141)Therapeutic anticoagulation (n = 141)
*P < 0.05, Wald’s test. **P < 0.05, KW ANOVA post-hoc Dunn’s test. IQR: interquartile range; BMI: body mass index; ACEI: angiotensin-converting enzyme inhibitor; ARB: angiotensin II receptor blocker; COPD: chronic obstructive pulmonary disease; HIV/AIDS: human immunodeficiency virus/acquired immunodeficiency syndrome; ICU: intensive care unit; tPA: tissue plasminogen activator; VTE: venous thromboembolism; ESRD: end-stage renal disease; CAD: coronary artery disease; PPI: proton pump inhibitor.
Demographic
  Age (years), median (IQR)66 (54 - 80)66 (55 - 76)
  Male, n (%)91 (67.4)99 (70.2)
  BMI (kg/m2), median (IQR)28.8 (26 - 32.7)30.8 (25.8 - 33.7)
Race/ethnicity
  Caucasian, n (%)87 (61.7)87 (61.7)
  Hispanic, n (%)36 (24.8)25 (17.7)
  African American, n (%)10 (7.1)14 (10.0)
  Asian, n (%)1 (0.7)1 (0.7)
  Other, n (%)8 (5.7)14 (9.9)
Comorbidities
  Hypertension85 (60.3)87 (61.7)
  Diabetes60 (42.6)62 (44.0)
  Asthma12 (8.5)19 (13.5)
  COPD10 (7.1)19 (13.5)*
  Atrial fibrillation12 (8.5)10 (7.1)
  Heart failure12 (8.5)9 (6.4)
  History of VTE4 (2.8)4 (2.8)
  CAD38 (27.0)36 (26)
  Chronic kidney disease21 (14.9)10 (7.1)*
  ESRD5 (3.6)0 (0)*
  Liver disease2 (1.4)1 (0.7)
  Cancer12 (8.5)11 (7.8)
  HIV/AIDS2 (1.4)2 (1.4)
  Smoking history4 (2.8)5 (3.6)
  Charlson Comorbidity Index (median)3 (1 - 4)3 (1 - 4)
Hospital interventions
  ICU13 (9.2)36 (25.5)*
  Intubation/ventilator14 (9.9)40 (28.4)*
  Steroids, n (%)112 (79.4)126 (89.4)*
  tPA, n (%)3 (2.1)14 (9.9)*
Home medications
  ACEI/ARBs, n (%)58 (41.3)66 (47.1)
  Antiplatelet, n (%)48 (33.7)48 (34.0)
  Anticoagulation, n (%)17 (12.1)13 (9.2)
  Statins, n (%)63 (44.7)65 (46.1)
  PPI, n (%)38 (27.0)49 (35.0)
Baseline vitals/labs
  Systolic blood pressure (mm Hg), median (IQR)128 (118 - 146)131 (115 - 142)
  Diastolic blood pressure (mm Hg), median (IQR)76 (67 - 85)79 (68 - 87)
  Respiratory rate (breaths/min), median (IQR)18 (17 - 20)18 (18 - 20)
  Oxygen saturation, median (IQR)96 (94 - 98)96 (94 - 98)
  D-dimer (µg/mL), median (IQR)0.98 (0.61 - 1.82)1.47 (0.8 - 2.9)
  D-dimer > 0.588%91%
  Platelet count, median (IQR)199 (160 - 260)216 (158 - 291)

 

Table 2. Primary and Secondary Outcomes
 
Prophylactic anticoagulation (n = 141)Therapeutic anticoagulation (n = 141)Odds ratio (95% CI)P value
*Statistically significant. CI: confidence interval; VTE: venous thromboembolism; LOS: length of stay; NA: not available.
30-day primary outcomes (n = 266)
  VTE, n (%)3 (2.2)5 (3.9)0.56 (0.2 - 2.0)0.5
  Mortality, n (%)7 (5.2)33 (25.4)0.16 (0.08 - 0.39)< 0.0001*
Unrestricted primary outcomes
  VTE, n (%)6 (2.9)8 (5.7)2.02 (0.7 - 5.2)0.2
  Mortality, n (%)8 (3.8)38 (27.0)9.2 (4.0 - 17.7)< 0.0001*
30-day secondary outcomes (n = 266)
  Hemorrhagic events n (%)14 (10)21 (16)0.6 (0.3 - 1.22)0.2
  Hospital LOS, median days (IQR)6 (4 - 11)8 (5 - 15)NA0.02*
Unrestricted secondary outcomes
  Hemorrhagic events n (%)15 (11)27 (19)0.5 (0.3 - 1.0)0.049*
  Hospital LOS, median days (IQR)6 (3 - 9)9 (6 - 18)NA0.003*

 

Table 3. Restricted Mean Survival Time (RMST) Analysis
 
GroupFailedTotalτRMST (τ)aStandard errorLower 95% CIUpper 95% CI
aEstimates are based on an interval upper limit of τ = 42.0, the smallest maximum observed time among all groups. CI: confidence interval; PPX: prophylaxis-intensity; TX: therapeutic-intensity.
PPX814142.034.92.37030.239.5
TX3814142.027.41.71224.030.7

 

Table 4. Cox Regression of Factors Related to Mortality
 
Independent variableRisk ratioP
aMeans the P value is referring to patients in the ICU (1) vs. patients not in the ICU (0), likewise for ventilator status. *Statistically significant. COPD: chronic obstructive pulmonary disease; ICU: intensive care unit; PPX: prophylaxis-intensity; TX: therapeutic-intensity.
ICU (1 - 0)2.1 (1.4 - 3.1)0.0002*
COPD (1 - 0)1.75 (1.1 - 2.7)0.01*
Age (≥ 65 - < 65)1.56 (1.1 - 2.3)0.02*
TX group (TX - PPX)1.34 (0.9 - 2.0)0.16
Ventilator1.1 (0.7 - 1.7)0.7
ICU (1 - 0)a ventilator (1 - 0)a0.46 (0.31 - 0.69)0.0002*