Younger patients with cancer may have a high risk of death from COVID-19, according to a meta-analysis published in JAMA Network Open.
Researchers found that being younger, having lung cancer, and having a hematologic malignancy were all associated with an increased risk of death from COVID-19.
The meta-analysis included 81 studies spanning 28 countries. The studies were case-control or cohort studies that involved 10 or more patients with malignant disease and COVID-19, with or without a control group. Each control group included patients without cancer who had COVID-19.
The studies encompassed a total of 61,532 patients with cancer, and 58,849 of them had adequate data available. Half of these patients were men (52%), and the median age ranged from 35 to 74 years across the studies.
The pooled relative risk (RR) of death was 2.12 in patients with cancer and COVID-19, compared with non-cancer patients who had COVID-19 (95% CI, 1.71-2.62; P <.001). When cancer patients and control individuals were matched by age and sex, the RR decreased to 1.69 (95% CI, 1.46-1.95; P <.001).
The risk of death from COVID-19 was significantly higher for patients with lung cancer than for patients with other cancers (RR, 1.68; 95% CI, 1.45-1.94; P <.001). The pooled case fatality rate for patients with COVID-19 and lung cancer was 30%.
The risk of death from COVID-19 was higher for patients with hematologic malignancies (RR, 1.42; 95% CI, 1.31-1.54; P <.001) than for those with solid tumors. The pooled case fatality rate for patients with COVID-19 and hematologic malignancies was 32%.
The researchers assessed the association between age and mortality in cancer patients compared with control individuals, and the results showed a significant decrease in the risk of death with increasing age (odds ratio, 0.96; 95% CI, 0.92-0.99; P =.03).
“Given these data, younger patients may be considered, in certain settings, to be a high-risk population for poor outcomes from COVID-19,” the researchers wrote. The team noted that prior studies reported increasing age as a risk factor for poor outcomes from COVID-19.
“To date, all of the cohort studies, which by their nature lacked an age-matched control group, have consistently reported increasing age as a risk factor for poor clinical outcome,” the researchers wrote. “Although it is true that older patients have worse absolute outcomes than younger patients, the RR data we found were highest for younger patients.”
“The reasons for this finding were likely associated with the type of cancer, the intensity of treatments, or behavioral factors, such as increased social mixing vs that of an older population,” the researchers wrote.
They noted several limitations to this study, including the fact that outcomes were only assessed for 7 tumor types. Other limitations were the lack of a control cohort for patients with solid tumors and the inability to assess outcomes with different SARS-CoV-2 variants.
“Ongoing studies … will enable a more comprehensive comparison of patients with cancer vs control patients, with adjustments for age, sex, and other comorbidities, and the identification of the true risk of different tumor types and treatments while controlling for patient-level factors,” the researchers wrote.
Disclosures: Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of disclosures.
Khoury E, Nevitt S, Madsen WR, et al. Differences in outcomes and factors associated with mortality among patients with SARS-CoV-2 infection and cancer compared with those without cancer. A systematic review and meta-analysis. JAMA Netw Open. Published online May 2, 2022. doi:10.1001/jamanetworkopen.2022.10880