Risk factors for COVID-19 in patients with hematological malignancies

Cancer patients have always been at higher risk of developing severe coronavirus disease 2019 (COVID-19) due to underlying malignancies that undermine the immune system and the frequent use of immunosuppressive treatments in these patients. Many patients and medical staff have had to make difficult decisions to delay or stop chemotherapy to better manage COVID-19 in these patients.

In a recent Health Science Reports Study, researchers examine the risk factors in people suffering from hematological malignancies and COVID-19.

To learn: Hematologic malignancies and COVID-19 infection: a single-center retrospective study. Photo credit: Chaikom / Shutterstock.com

About the study

The current study was conducted at Taleghani Hospital and included the analysis of patients’ medical history, comorbidities, chemotherapeutic regimens and phase of hematological treatment. Patients with a history of allogeneic or autologous hematopoietic stem cell transplantation as well as patients with other explanations for pneumonia were excluded from the current study.

All patients had to have undergone computed tomography (CT) to confirm COVID-19 pneumonia. Laboratory tests were also performed to collect data for complete blood count (CBC), liver and kidney function, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and other inflammatory markers such as lactate dehydrogenase (LDH).

The included patients had different diseases and were therefore divided according to treatment phases. These phases included pre-induction, induction, consolidation, maintenance, and refractory.

Some of the diseases these patients suffered from were acute myeloid leukemia (AML), acute lymphoblastic leukemia (ALL), Hodgkin’s and non-Hodgkin’s lymphoma, multiple myeloma, myelodysplastic syndromes, hairy cell leukemia, and hemophagocytic lymphohistiocytosis.

Each patient in the pre-induction phase was eligible to start chemotherapy but had not yet done so due to COVID-19. In comparison, those in the induction phase received chemotherapy when they became positive for COVID-19.

The consolidation phase included AML or ALL patients who were in remission and patients who had recently received chemotherapy and were diagnosed with cytopenia. The maintenance phase included remission patients receiving long-term chemotherapy. Finally, the refractory period included patients who did not respond to any type of chemotherapy and still had active disease.

Endpoints for the current study included incidence of COVID-19, intensive care unit (ICU) admission, therapies received, patient outcome, length of hospital stay, and any change in pre-existing comorbidities. Quantitative and qualitative data were presented as mean, median and frequency.

study results

A total of 194 inpatients with hematological malignancies and COVID-19 were included in the current retrospective study. Logistic regression models were built showing that the strongest predictor of death was ICU admission, with ICU patients being 23.35 more likely to die than others.

While some studies have shown that men are more likely to have severe COVID-19 compared to women, this does not appear to be the case in patients with hematological malignancies. In fact, women were 3.48 times more likely to die than men. Age was also associated with an increased risk of death, while length of hospital stay was associated with a reduced risk of death.

Several different inflammatory markers have been linked to mortality from different diseases. For example, ESR has been associated with an increased risk of death in patients with ALL, myelodysplastic syndromes, hairy cell leukemia, and hemophagocytic lymphohistiocytosis.

In comparison, higher levels of LDH were associated with an increased risk of death in patients with lymphoma and multiple myeloma. Elevated ferritin levels were also a significant predictor of death in multiple myeloma patients.

Higher levels of fibrinogen were associated with higher overall mortality rates. In addition, high levels of ESR, LDH, and fibrinogen were associated with lower oxygen saturation.

Conclusions

Several different risk factors have been identified in patients with hematological malignancies who subsequently become infected with SARS-CoV-2. Identifying these risk factors could help improve hospital triage and better inform medical staff about which subset of patients with specific hematological malignancies are at increased risk for severe COVID-19 and death.