A STUDY has revealed that patients with asthma have an elevated risk for several cancer types, including blood, melanoma, ovarian, kidney, and lung cancers.
The University of Florida, Gainsville, USA, which carried out the study, found a 1.36-fold increased risk of developing cancer if the patient already had asthma (99% confidence interval [CI]: 1.29–1.44). The cohort included 90,000 patients with asthma, whose electronic health records from between 2012–2020 were held in the OneFlorida+ Clinical Research Network, which holds data from around 20 million individuals. Data was compared to a group of approximately 270,000 adults who did not have respiratory diseases.
Researchers found an increased risk for those with asthma in developing melanoma (hazard ratio [HR]: 1.98; 99% CI: 1.67–2.36), ovarian cancer (HR: 1.88; 99% CI: 1.40–2.51), kidney cancer (HR: 1.48; 99% CI: 1.11–1.99), lung cancer (HR: 1.56; 99% CI: 1.33–1.83), and blood cancer (HR: 1.26; 99% CI: 1.08–1.47).
The study also identified the potential protective effect of inhaled steroid use against cancer development. The cohort of patients with asthma was divided into two groups, one that used inhaled steroids, and one that did not. Cancer risk was still found to be elevated in both groups, but the group who used inhaled steroids were less likely to develop cancer.
Those diagnosed with asthma have complex chronic inflammation in their bodies, related to the disease. Inflammation has also been linked to tumour development. Results from the study led researchers to believe that inflammation could be the link between both diseases.
Yi Guo, Department of Health Outcomes and Biomedical Informatics, University of Florida College of Medicine, was part of the study. Guo revealed: “We identified an association between asthma and elevated cancer risk, although we are not claiming that asthma causes cancer; we’re only saying that there is a connection between the two.” Guo went on to stress that further research is needed, and encouraged other researchers to help “determine whether there is a causal effect.”