Incidence of Thrombotic Events and Outcomes in COVID-19 Patients Admitted to Intensive Care Units

Introduction While coronavirus disease 2019 (COVID-19) mostly causes respiratory illnesses, emerging evidence has shown that patients with severe COVID-19 can develop complications like venous thromboembolism (VTE) and arterial thrombosis as well. The incidence of thrombosis among critically ill patients in the literature has been highly variable, ranging from 25 to 69%. Similarly, reported mortality among critically ill patients has been highly variable too, and it has ranged from 30 to 97%. In this study, we analyzed data from a large database to address the incidence, the risk factors leading to thrombotic complications, and mortality rates among COVID-19 patients. Material and methods Data were obtained from TriNetX (TriNetX, Inc., Cambridge, MA), a multinational clinical research platform that collects medical records from 42 healthcare organizations (HCOs). All nominal data were compared using the chi-squared test. Alpha of <0.05 was considered statistically significant. We used Benjamini-Hochberg correction with a false discovery rate of 0.1 to correct for multiple comparisons. Results We identified 18,652 COVID-19-positive patients, with a median age of 50.7 years [interquartile range (IQR): 31.8-69.6]; among them, 51.8% (9,672) were males and 48.2% (8,951) were females. Of these patients, 630 [3.37%; median age: 61 years (IQR: 44.9-77.1)] were critically ill, requiring intensive care unit (ICU) care within one month of their diagnosis. Men were over-represented among the ICU patients when compared to women (3.7% vs 3%, p=0.009, Χ²=6.66). African Americans were over-represented among the ICU patients when compared to Caucasians (8.5% vs 4%, p<0.0001, Χ²=76.65). Older patients, i.e., 65 years and older, were over-represented in the ICU compared to patients aged 18-64 years (6.8% vs 2.5%, p<0.0001, Χ²=121.43). The cumulative incidence of thrombotic events in the ICU population was 20.4% (129/630). Thrombotic events were significantly more common in patients who were 65 years and older when compared to patients in the age group of 18-64 years (24.6% vs 17.31%, p=0.02, Χ²=5.38). Mortality among ICU patients was higher in those who were 65 years and older when compared to the age group of 18-64 years (31.9% vs 17.3% p=0.0003, Χ²=18.41). The overall mortality in the study population was higher in patients who were 65 years and older when compared to patients aged 18-64 years (18.55% vs 1.4%, p<0.0001, Χ²=1915). Conclusions Among COVID-19 patients, men, African Americans, and people who are 65 years and older are more likely to have severe disease and require ICU level of care. Patients who are 65 years and older are more likely to have thrombotic events, myocardial infarction (MI), and stroke. Overall mortality and ICU mortality are higher among COVID-19 patients who are 65 years and older.