TORONTO -- New research from the United Kingdom suggests shift workers are associated with higher likelihoods of COVID-19 hospitalization compared to people with more traditional working hours.
Using data from more than 280,000 participants in the U.K. Biobank study, hospital episode statistics and U.K. health records, the researchers at the University of Manchester, the University of Oxford and the University of the West Indies found that those who work irregular night shifts were three times more likely to test positive for COVID-19 in hospitals.
Additionally, the researchers found that irregular shift workers were twice as likely test positive for COVID-19 and those doing permanent shift work were 2.5 times more likely to test positive for COVID-19.
The study, published Monday in the online journal the Thorax, found that the elevated risks in shift work remained unchanged even after taking into account other risk factors such as sleep deprivation, body mass index (BMI) and smoking.
"This study shows quite a strong association between shift working and being hospitalised for COVID-19, even after controlling for existing COVID-19 risk factors,” Dr. John Blaikley, a clinician scientist at the University of Manchester and one of the authors of the study, said in a news release.
The study also found that shift workers are more likely to test positive for COVID-19 regardless of type of work the person is doing and regardless of whether the shift is during the day or night.
Given the size of the association found in this study, the researchers note that the risk of shift work is comparable to other known COVID-19 risk factors, including ethnicity, socioeconomic status and BMI.
“A key difference with shift work compared with most other COVID-19 risk factors is that this risk could be mitigated relatively quickly,” the researchers wrote in the study. “Possible solutions are increasing distance between workers, wearing personal protective equipment and enhanced cleaning of the workspace.”
The researchers hypothesize several possible explanations for this association: increased occupancy at these workplaces, reduced cleaning time between shifts and disruptions to the body’s natural rhythm, to name a few.
Health risks associated with shift work are fairly well known. Other research has found shift workers are more prone to infections, respiratory disease, diabetes and cancer.
There are several limitations to this study, however, including that the data can not establish cause, and that data from the U.K. Biobank was collected between 2006 and 2010, though parts of it have been updated.
