Thrombotic Outcomes in Patients With Hematologic Malignancies and COVID-19

Take-aways:

• Rates of cerebrovascular accident and venous thromboembolism were significantly increased in patients with hematologic malignancies (HM) and acute COVID-19.
• Patients with HM were also found to have higher fatality rates and a significantly increased need for intensive care and respiratory support.
• Further research is required to understand the natural history of COVID-19 in patients with HM and to better inform management of this population.

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Patients with hematologic malignancies (HM) have a significantly higher rate of composite thrombotic outcomes during acute COVID-19 infection, compared with the general population. This is according to findings published in Clinical Lymphoma, Myeloma & Leukemia.

Researchers led by Michael R. Cook, MD, performed a retrospective analysis of the thrombotic and clinical outcomes of patients with a history of hematologic malignancy and acute COVID-19 infection.

Out of 833 evaluable patients with COVID-19 identified via electronic health record at MedStar Georgetown University Hospital/Washington Hospital Center by positive SARS-CoV-2 PCR test during an emergency department visit or inpatient admission, 124 also had hematologic malignancies (HM). The outcomes of patients with HM were compared with the remaining 709 who served as the general population (GP) cohort.

The investigators analyzed demographic information (age, race, sex, BMI, VTE history prior to COVID-19) as well as clinical information from the emergency department encounter or hospitalization related to COVID-19 (admission and discharge dates, laboratory results, new VTE/CVA, inpatient respiratory support, intensive care unit [ICU] admission, days in ICU, days on ventilator, and death). They also examined further information on patients in the HM cohort, including type of HM, treatment and remission status, date of last clinical follow-up or death.

In the HM cohort, the most common diseases were as follows:

• plasma cell dyscrasia (28.2%; n=35)
• non-Hodgkin lymphoma (25%; n=31)
• chronic lymphocytic leukemia (16.9%; n=21)

Remission status was documented in 57.3% (n=71) of patients in the HM group. Among patients with a documented remission status, at the time of COVID-19 infection, 25.4% (n=18) had a complete remission (CR), 18.3% (n=13) had a partial remission, 43.7% (n=31) had stable disease, and 12.7% (n=9) had progressive disease. Thirty-nine patients (31.5%) were treatment-naïve or did not have an evaluated remission status, while remission status and treatment status were unknown for 14 and 13 patients, respectively.

Rates of VTE and cerebrovascular accident (CVA) in the HM cohort compared to the general population cohort represented the primary endpoints of the study. Secondary endpoints were composite thrombotic events (VTE and CVA), COVID-19-related mortality, ICU admission rates, length of ICU stay and ventilator requirement, and complete blood count/LDH levels at presentation.

CVA was reported in 5.4% of patients with HM, compared to 1.6% of patients in the GP (P = 0.011). The incidence of VTE was 8% in the HM group versus 3.6% in the GP (P = 0.069). In patients with HM, a composite thrombotic rate of CVA and VTE was 13.4%, compared with 5.2% in the GP (P = 0.005).

Among patients with HM, the inpatient fatality rate was 35.5% (n=44) versus 11.3% (n=80) in the GP (P <0.001). Respiratory support was required for 74.6% of patients in the HM cohort, compared with 46.5% in the GP (P <0.001). In the HM cohort and GP, respectively, 31.9% and 12.1% of patients required admission to the ICU (P <0.001). Median ICU stay was 6 days for patients with HM versus 5 days for GP (P = 0.192). Duration of ventilator support was 8 days for patients with HM and 6 days for GP (P = 0.326).

At presentation with COVID-19, median absolute lymphocyte count was 1.1 for patients with HM and 1.15 in the GP (P = 0.900). Median LDH was 318 versus 358 (P = 0.116) for the respective populations.

No differences in overall survival or primary and secondary endpoints were observed among patients with HM in CR compared with other remission status, or between patients on active treatment and maintenance or surveillance treatment.

“Based on our results, we recommend patients with HM be treated with anticoagulation strategies that match the literature for the general population,” the authors wrote. However, they added, “more data may be needed before definitive recommendations can be made.”

One limitation of this analysis is the higher rate of historical VTE prior to COVID-19 in the HM cohort. Some patients received anticoagulation before and during hospitalization, which may have lowered thrombotic complications in this group.

Disclosures: Study authors reported no relevant conflicts of interest.

Reference

Cook MR, Dykes K, White K, et al. Thrombotic and Clinical Outcomes in Patients with Hematologic Malignancy and COVID-19. Clin Lymphoma Myeloma Leuk. 2021 Dec 26;S2152-2650(21)02482-4.