Impact of Thromboprophylaxis Intensity on Patients' Mortality Among Hospitalized Patients with COVID-19: A Propensity-Score Matched Study

Sumaya N Almohareb; Majed S Al Yami; Ahmed M Assiri; Omar A Almohammed

doi:10.2147/CLEP.S359132

Impact of Thromboprophylaxis Intensity on Patients' Mortality Among Hospitalized Patients with COVID-19: A Propensity-Score Matched Study

Clin Epidemiol. 2022 Mar 19:14:361-368. doi: 10.2147/CLEP.S359132. eCollection 2022.

Authors

Sumaya N Almohareb^{1

2

3}, Majed S Al Yami^{1

2

3}, Ahmed M Assiri⁴, Omar A Almohammed^{5

6}

Affiliations

¹ Department of Pharmacy Practice, College of Pharmacy, King Saud bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia.
² Department of Clinical Pharmacy, King Abdulaziz Medical City, Riyadh, Saudi Arabia.
³ King Abdullah International Medical Research Center, Ministry of National Guard Health Affairs, Riyadh, Saudi Arabia.
⁴ Health Volunteering Center, Ministry of Health, Riyadh, Saudi Arabia.
⁵ Department of Clinical Pharmacy, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia.
⁶ Pharmacoeconomics Research Unit, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia.

Abstract

Purpose: Venous thromboembolism (VTE), a major complication that has been reported in patients with COVID-19, is associated with an increased risk of mortality. The purpose of this study was to compare in-hospital mortality among hospitalized patients with COVID-19 who received high-intensity versus standard-intensity thromboprophylactic anticoagulation.

Patients and methods: A secondary database analysis was conducted using data for adult patients who were hospitalized for COVID-19 in Saudi Arabia and received enoxaparin for thromboprophylaxis during their hospitalization. While enoxaparin 40 mg daily is considered the standard-intensity, doses higher than the standard but not to reach the therapeutic dose were considered as high-intensity. The primary outcome in the study was in-hospital mortality, and the secondary outcomes included intensive care unit (ICU) and hospital length of stay. Chi-square and t-tests were used to assess the difference between the two independent groups, and propensity score matching was performed to adjust for baseline characteristics.

Results: From 3508 patients who received high- or standard-intensity enoxaparin, 1422 patients, 711 in each group, were included in the analyses after propensity score matching. The mean age of the participants was 57.2 years, and around 30% of them were female. About 72% of the patients were admitted to the ICU. No difference was observed between the two groups in the in-hospital mortality outcome (36% vs 33.5% in the high-intensity and the standard group, respectively; RR=1.06, 95% CI 0.95-1.18). However, patients who received high-intensity thromboprophylaxis had a significantly longer duration of hospitalization (15.6 days vs 13.6 days; p=0.003) and ICU stay (12.3 days vs 10.8 days; p=0.039) compared to patients who received the standard dose.

Conclusion: The use of high-intensity thromboprophylaxis was not associated with a reduction in mortality. Therefore, our results do not support the routine use of high-intensity prophylactic anticoagulation in both ICU and non-ICU patients with COVID-19.

Keywords: COVID-19; anticoagulation; mortality; thromboprophylaxis; venous thromboembolism.

Grants and funding

The author (OAA) received a fund from the Researcher Supporting Project number (RSP-2021/77), King Saud University, Riyadh, Saudi Arabia, to support the publication of this article. The funding agency had no role in designing the study, conducting the analysis, interpreting the data or writing the manuscript.