Did COVID-19 mortality differ between patients with cancer and the general US population depending on which SARS-CoV-2 variant was dominant?

By Pooja Toshniwal PahariaReviewed by Sophia CoveneySep 4 2023

In a recent study published in JAMA Oncology, researchers comparatively evaluated coronavirus disease 2019 (COVID-19)-related mortality among cancer patients and the general public of the United States (US) during different periods of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreak.

Background

The increasing percentage of hospitals in the United States opting to eliminate COVID-19 masking rules has raised significant controversy regarding the timing of the removal of masking restrictions since hospitals are high-risk environments for contracting SARS-CoV-2. Studies have also reported that COVID-19 incidence is higher among cancer patients than the general public.

With the continuous relaxation of procedures to curtail SARS-CoV-2 transmission, cancer patients may face a higher burden of death from COVID-19 than the general public.

Investigating COVID-19-associated mortality rates in different periods of the COVID-19 pandemic, characterized by the predominance of different SARS-CoV-2 variants of concern (VOCs), varied vaccination rates, and changes in COVID-19 prevention measures, may provide insight into future COVID-19-associated mortality risk among cancer patients.

About the study

In the present retrospective, population-based, cross-sectional study, researchers examined COVID-19-associated mortality among cancer patients and the general public of the United States between 1 March 2020 and 31 May 2022.

Researchers aimed to investigate whether COVID-19-associated mortality differed between cancer patients and the US general public during periods of different SARS-CoV-2 variant dominance.

Data were obtained from the Centers for Disease Control and Prevention's (CDC) Wide-Range Online Data for Epidemiologic Research (WONDER) database.

Using mortality ratios, COVID-19-associated mortality rates during the SARS-CoV-2 Omicron variant peak in winter between 2021 and 2022 were compared to mortality during the winter of the preceding year (during SARS-CoV-2 Wuhan-Hu-1 strain predominance). Data was evaluated between July 21 and 31 August 2022.

COVID-19 wave during the Wuhan-Hu-1 strain (between December 2020 and February 2021), the Delta variant (between July and November 2021), or the Omicron variant (between December 2021 and February 2022) predominance was the research exposure. The outcome measure was monthly COVID-19-associated fatalities.

To investigate COVID-19 mortality among cancer patients, the researchers chose people who had both cancer and COVID-19 as reasons for death. Death certificates were retrieved to obtain race information and assess the demographic features of the sample population during the Wuhan-Hu-1, Delta, and Omicron periods. Age and cancer location were used to conduct subgroup analysis.

Results

The study comprised 628,156 individuals from the general population of the US and 34,350 cancer patients (42% female,n=14,498; 58% male, n=19,852) with COVID-19-associated deaths during Wuhan-Hu-1, Delta, and Omicron predominance.

The highest COVID-19-associated deaths (n=5,958) among cancer patients were observed during Omicron predominance. During the peak Omicron wave, 18% higher mortality was reported compared to that during the Wuhan-Hu-1 strain peak.

On the contrary, in the general population of the US, most deaths from COVID-19 were reported during Wuhan-Hu-1 predominance (105,327 deaths), with 21% lower COVID-19-associated deaths during the Omicron wave between December 2021 and February 2022 compared to the Wuhan-Hu-1 peak period.

COVID-19-associated mortality rose the most (38%) in lymphoma patients during Omicron predominance in winter versus Wuhan-Hu-1 predominance, according to subgroup analysis by cancer location.

COVID-19-associated mortality was the highest among cancer patients aged less than 80 years during the winter of the Omicron dominant period. Monthly COVID-19 mortality rates during Omicron peak in winter between 2021 and 2022 among cancer patients aged below 50 years, 50 to 59 years, 60 to 69 years, and 70 to 79 years were 64%, 62%, 31%, and 16% higher, respectively, compared to mortality rates during Wuhan-Hu-1 predominance.

The greatest percentage of deaths from COVID-19 per month in the overall population occurred during Delta predominance among individuals aged below 50 years and those aged between 50 and 59 years. The most COVID-19 fatalities per month occurred among individuals aged 60 to 69 years, 70 to 79 years, and 80 years and above during Wuhan-Hu-1 predominance.

Conclusions

Overall, the study findings showed that during the Omicron wave in winter, COVID-19 mortality rates were higher among cancer patients compared to the general public in the United States.

The prevention of SARS-CoV-2 transmission must be prioritized in light of the continual emergence of novel, increasingly immune-evasive, and transmissible SARS-CoV-2 variants of concern, of which many are predicted to show resistance toward monoclonal antibodies.