Air pollution ‘significantly’ increases hospital risk for childhood cancer survivors

Days with high levels of PM2.5 pollution ‘significantly’ increase the risk of hospitalisations for childhood cancer survivors, according to a study published in the International Journal of Environmental Research and Public Health.

In a first of its kind study, US researchers at Huntsman Cancer Institute (HCI) at the University of Utah (U of U) studied medical records of almost 4,000 childhood, adolescent, and young adult cancer survivors diagnosed or treated at Primary Children’s Hospital in Salt Lake City between 1986 and 2012.

They then tracked when and how often those survivors required emergency treatment or were admitted to the hospital due to respiratory illness.

The study was divided into three groups: those who received chemotherapy as part of their cancer treatment, those who didn’t receive chemotherapy, and a cancer-free group, which found the risk for respiratory hospitalisation was significantly higher among the survivors who received chemotherapy compared to the cancer-free group.

They then specifically looked at what happened to survivors on unhealthy air days, finding the risk for hospitalisations among cancer survivors was significant when air pollution (PM2.5) was below the standard for sensitive groups (35.4 μg/m3), which they say confirms that levels below that protective standard may still contribute to respiratory problems for cancer survivors.

Researchers believe that survivors of childhood cancers may have a higher vulnerability to high levels of PM2.5 because of lung damage and potential immunosuppression resulting from cancer and treatment with chemotherapy.

Judy Ou, PhD, a cancer epidemiologist at HCI and lead author on the study said: ‘There are approximately 17 million cancer survivors in the United States, and statistics show about 40% of the U.S. population lives in places that are considered polluted at certain times of the year.

‘This study provides valuable information to the medical community about how air pollution affects young survivors of cancer. We can use this to inform strategies to address this risk.’

In the UK, Public Health England warned last year that air pollution could be costing the NHS and the economy £5.3bn by 2035 unless urgent action is taken.