Effectiveness of COVID-19 Vaccination in Hematologic Cancer Patients
Overview
This nationwide Dutch cohort study found that patients with hematologic malignancies have the highest risk of severe COVID-19 outcomes compared to those with solid malignancies or no cancer. COVID-19 vaccination reduced the risk of severe disease by up to 74%, although these patients remained at elevated risk relative to others.
Background
Patients with hematologic malignancies are immunocompromised due to their disease and treatments, placing them at increased risk for severe COVID-19. Early in the pandemic, these patients showed higher COVID-19 mortality, prompting prioritization for vaccination including additional doses. While vaccine immunogenicity varied by malignancy type and therapy, clinical vaccine effectiveness data in this population were lacking. This study aimed to fill that gap by analyzing nationwide data on COVID-19 outcomes in patients with hematologic cancers.
Data Highlights
Group
Risk of Severe COVID-19
Vaccine Effectiveness Against Severe COVID-19
Hematologic Malignancies
Highest risk among groups
Up to 74% (95% CI, 60%-83%)
Solid Malignancies
Intermediate risk
Not specified
No Malignancies
Lowest risk
Not specified
Key Findings
Patients with hematologic malignancies had the highest risk of COVID-19-related hospitalization or death after SARS-CoV-2 infection.
COVID-19 vaccine effectiveness against severe disease in these patients reached up to 74%, varying by variant period, vaccination number, and time since vaccination.
Risk of severe COVID-19 was greatest in recently diagnosed hematologic malignancy patients and decreased over time, except in chronic malignancies.
Tumor-specific treatments such as CD38 and CD20 antibodies, proteasome inhibitors, and protein kinase inhibitors were associated with higher risk of severe COVID-19.
Patients with hematologic malignancies remained at elevated risk despite vaccination compared to patients with solid malignancies or no malignancies.
Determinants of severe COVID-19 included malignancy type, timing of diagnosis relative to infection, and ongoing treatment regimens.
Clinical Implications
Healthcare providers should recognize that patients with hematologic malignancies remain at elevated risk for severe COVID-19 despite vaccination and may benefit from additional preventive measures and therapeutic strategies. Vaccination remains a critical tool to reduce severe outcomes in this vulnerable population. Consideration of malignancy type, treatment status, and timing since diagnosis is important when assessing COVID-19 risk and planning care.
Conclusion
COVID-19 vaccination significantly reduces severe disease risk in patients with hematologic malignancies, but these patients continue to face higher risks than others. Tailored prevention and treatment strategies are needed to protect this vulnerable group.
References
Dutch Nationwide Cohort Study 2022 -- Effectiveness of COVID-19 Vaccination in Individuals with Hematologic Cancers
by Quincy Hofsink, Birgit I Lissenberg-Witte, Sabine Haggenburg, Abraham Goorhuis, Mette D Hazenberg, Caroline E Rutten, Paul den Tex, Elisabeth G E de Vries, Astrid A M van der Veldt, Jeanet M Kemmeren, Nicolette F de Keizer, Peter C Huijgens, Avinash G Dinmohamed, Annika van Roon, Joyce Pijpers, Caren van Roekel, Susan van den Hof, Susan J M Hahné, Brechje de Gier, Jarom Heijmans, Inger S Nijhof
