A new study underscores the importance of COVID-19 and regular COVID-19 testing among adults with a recent cancer diagnosis.
The Indiana statewide study, conducted at the beginning of the pandemic, found that
“This analysis provides additional empirical evidence on the magnitude of risk to patients with cancer whose immune systems are often weakened either by the disease or treatment,” the study team wrote.
The study was published online in JMIR Cancer.
Although evidence has consistently revealed similar findings, the risk of death among unvaccinated people with cancer and COVID-19 has not been nearly as high in previous studies, lead author Brian E. Dixon, PhD, MBA, with Indiana University Richard M. Fairbanks School of Public Health, Indianapolis, said in a statement. Previous studies from China, for instance, reported a two- to threefold greater risk of all-cause mortality among unvaccinated adults with cancer and COVID-19.
A potential reason for this discrepancy, Dr. Dixon noted, is that earlier studies were “generally smaller and made calculations based on data from a single cancer center or health system.”
Another reason is testing for COVID-19 early in the pandemic was limited to symptomatic individuals who may have had more severe infections, possibly leading to an overestimate of the association between SARS-CoV-2 infection, cancer, and all-cause mortality.
In the current analysis, researchers used electronic health records linked to Indiana’s statewide SARS-CoV-2 testing database and state vital records to evaluate the association between SARS-CoV-2 infection and all-cause mortality among 41,924 adults newly diagnosed with cancer between Jan. 1, 2019, and Dec. 31, 2020.
Most people with cancer were White (78.4%) and about half were male. At the time of diagnosis, 17% had one comorbid condition and about 10% had two or more. Most patients had breast cancer (14%), prostate cancer (13%), or melanoma (13%).
During the study period, 2,894 patients (7%) tested positive for SARS-CoV-2.
In multivariate adjusted analysis, the risk of death among those newly diagnosed with cancer increased by 91% (adjusted hazard ratio, 1.91) during the first year of the pandemic before vaccines were available, compared with the year before (January 2019 to Jan. 14, 2020).
During the pandemic period, the risk of death was roughly threefold higher among adults 65 years old and older, compared with adults 18-44 years old (aHR, 3.35).
When looking at the time from a cancer diagnosis to SARS-CoV-2 infection, infection was associated with an almost sevenfold increase in all-cause mortality (aHR, 6.91). Adults 65 years old and older had an almost threefold increased risk of dying, compared with their younger peers (aHR, 2.74).
Dr. Dixon and colleagues also observed an increased risk of death in men with cancer and COVID, compared with women (aHR, 1.23) and those with at least two comorbid conditions versus none (aHR, 2.12). In addition, the risk of dying was 9% higher among Indiana’s rural population than urban dwellers.
Compared with other cancer types, individuals with lung cancer and other digestive cancers had the highest risk of death after SARS-CoV-2 infection (aHR, 1.45 and 1.80, respectively).
“Our findings highlight the increased risk of death for adult cancer patients who test positive for COVID and underscore the importance to cancer patients – including those in remission – of vaccinations, boosters, and regular COVID testing,” Dr. Dixon commented.
“Our results should encourage individuals diagnosed with cancer not only to take preventive action, but also to expeditiously seek out treatments available in the marketplace should they test positive for COVID,” he added.
Support for the study was provided by Indiana University Simon Cancer Center and the Centers for Disease Control and Prevention. The authors have disclosed no relevant financial relationships.