TORONTO -- A new study suggests that people with specific sleep disorders may be at risk of more severe outcomes if they contract COVID-19, with a 31 per cent higher rate of hospitalization and mortality.
The study, conducted by the Cleveland Clinic and , looked at data from around 5,400 patients at the clinic.
They found that while those with sleep disorders don’t contract COVID-19 at higher rates than others, they do have worse outcomes if they catch the virus.
"As the COVID-19 pandemic continues and the disease remains highly variable from patient to patient, it is critical to improve our ability to predict who will have more severe illness so that we can appropriately allocate resources," Dr. Mehra, director of Sleep Disorder Research at Cleveland Clinic, "This study improved our understanding of the association between sleep disorders and the risk for adverse COVID-19 outcomes. It suggests biomarkers of inflammation may mediate this relationship.”
Researchers looked at the clinic’s database of patients who had been tested for COVID-19, focusing on the 5,400 patients for whom the clinic also had sleep data.
The study pointed out that there is “a strong overlap between sleep-disordered breathing (SDB) […] and comorbidities associated with COVID-19 severity,” but that while SDB has been correlated in observational studies with a higher risk for poor COVID-19 outcomes, sleep disorders themselves have not been focused on for a study relating to COVID-19.
SDB is a generalized term that encompasses different breathing difficulties that a person may have while sleeping, including things like sleep apnea.
Researchers looked at patients who had different measures of SDB, as well as patients who had sleep-related hypoxia, which is when there isn’t enough oxygen intake to support your tissues.
Out of the 5,400 patients who had sleep data, 1,935, or 35 per cent, had tested positive for COVID-19 at some point. Fifty per cent of them, or 1,018 patients, had SDB.
“Sleep-related hypoxia measures were significantly associated with increasing WHO-designated clinical outcomes COVID-19 ordinal scale scores even after adjusting for patient characteristics, BMI, comorbidities, smoking history, and health care system site,” the study stated.
Those with sleep-related hypoxia had a 31 per cent higher risk of hospitalization and mortality.
“Our findings suggest that baseline sleep-related hypoxia is associated with progression of hypoxic insult and hypoxia-related injury in COVID-19 pathophysiology, hence serving as an amplifier,” the study stated.
The study added that the reasons for this are likely multi-faceted, as hypoxia can affect all of the tissues of the body to varying degrees in different patients, leading to different outcomes.
Researchers say that further studies should be done to figure out if early treatments such as PAP (positive airway pressure) or the administration of oxygen could improve COVID-19 outcomes in these patients.
"Our findings have significant implications as decreased hospitalizations and mortality could reduce the strain on healthcare systems," Cinthya Pena Orbea, M.D, of Cleveland Clinic's Sleep Disorders Center and first author of the study, said in the release.
“If indeed sleep-related hypoxia translates to worse COVID-19 outcomes, risk stratification strategies should be implemented to prioritize early allocation of COVID-19 therapy to this subgroup of patients."
