Cancer survivors diagnosed more than five years ago had a lower risk of hospitalization and severe outcomes when diagnosed with Covid-19 compared to individuals without a cancer history, a Korean study showed.
The study, led by Professor Park Jae-min from the Department of Family Medicine at Uijeongbu Eulji University Hospital and Professor Lee Jin-yong of the Public Healthcare Center at Seoul National University Hospital, revealed the relationship between Covid-19 outcomes and a history of cancer.
The research team analyzed data from over 790,000 patients aged 40 to 79 diagnosed with Covid-19 between January 2020 and March 2022. The study aimed to understand the varying risks of hospitalization, severe hospitalization, and death based on the presence and recency of a cancer diagnosis.
Leveraging extensive data from the Korea Centers for Disease Control and Prevention and the National Health Insurance Service, the researchers conducted a one-to-one matching method to compare outcomes between 397,050 patients with a history of cancer and an equal number without such a history.
The study's findings showed that Covid-19 patients with a history of cancer exhibited significantly higher rates of hospitalization and mortality (11.1 percent hospitalized, 1.0 percent died), compared to those without a cancer history (10.2 percent hospitalized, 0.5 percent died).
However, when the data was analyzed by the time of cancer diagnosis, a nuanced picture emerged.
The risk of Covid-19 hospitalization was found to be 0.96 times greater for cancer survivors diagnosed more than five years ago, 1.10 times greater for those diagnosed two to five years ago, 1.30 times greater for those diagnosed one to two years ago, and 1.82 times greater for those diagnosed less than one year ago.
Similarly, the risk of hospitalization due to severe Covid-19 was 0.90 times greater for cancer survivors diagnosed more than five years ago, 1.22 times greater for those diagnosed two to five years ago, 1.60 times greater for those diagnosed one to two years ago, and 2.29 times greater for those diagnosed less than one year ago compared to individuals with no history of cancer.
In essence, the study suggests that while individuals recently diagnosed with cancer face an elevated risk of Covid-19 hospitalization and severe outcomes, long-term cancer survivors, diagnosed more than five years ago, exhibit lower risks.
"Cancer survivors naturally become more health conscious during treatment and tend to adopt better health behaviors to manage their health,” Professor Park said.
"Instead of being discouraged or frustrated by a cancer diagnosis, taking good care of your health by living a healthy lifestyle, not smoking, getting immunizations, and managing co-occurring chronic conditions can lead to a healthier life."
The study has been published in the Journal of Korean Medical Science, an internationally recognized journal with SCI ranking.