FACTORS AFFECTING COVID-19 OUTCOMES IN PATIENTS WITH HEMATOLOGICAL MALIGNANCIES.

Abstract

Background: Patients with hematological malignancies (HM) are considered to have a high risk of developing severe and life-threatening infections including COVID-19 because of immune deficiency and immunosuppressive treatments. Although the COVID pandemic spread worldwide, morbidity and mortality data varied from country to country. A more accurate identification of risk factors would allow the improvement of the clinical management of HM patients.

Aim: This study aimed to determine real-life data - the mortality rate, clinical outcomes, and risk factors affecting mortality in patients with HM and COVID-19 at the Riga East University Hospital (REUH) in Latvia.

Materials and methods: In this retrospective non-interventional cohort study, we included adult patients treated in REUH with ongoing HM and laboratory- confirmed COVID-19 observed between December 1st, 2020, and March 31st, 2023. All data were analyzed using descriptive statistics, binary logistic regression, univariable Cox regression model, and other methods.

Results: We registered 156 patients with 11 different HMs. Multiple myeloma, non-Hodgkin lymphoma, and acute myeloid leukemia were the most common HM. COVID-19 mortality rate was 19.9% (31/156). Factors increasing the risk of death included the severity of COVID-19 (p < 0.001), the accession of bacterial infection (p < 0.001), longer hospital stay (p = 0.037), absolute neutrophil count (ANC) ≤ 0.5 × 109/mm3 (p = 0.014), fever (p = 0.039), and acute myeloid leukemia (p = 0.002). We also confirmed that the mortality in the third pandemic wave was significantly lower than in the second wave (p = 0.002). Although vaccination seemed to be a risk-mitigating factor (58.8% [10/17] of those who died from COVID-19 were not vaccinated), no statistically important correlation was found (p = 0.690).

Conclusion: This survey confirmed that the COVID-19 mortality rate was higher in patients with HM (19.9% [31/156]) than in the population. ANC, severity of COVID-19, accession of bacterial infection, hospital stay, fever, and acute myeloid leukemia were the factors that increased mortality in HM patients.