People who have been diagnosed with obstructive sleep apnea (OSA) could be at increased risk of adverse outcomes from COVID-19, according to a new study from the University of Warwick in Coventry, U.K. 
The conclusion is drawn from a systematic review of studies that reported outcomes for COVID-19 patients who were also diagnosed with OSA. Published in the journal Sleep Medicine Reviews, the study highlights the need to further investigate the impact of the virus on those with the sleep condition, and to better identify those currently undiagnosed with it.
Many of the risk factors and comorbidities associated with sleep apnea, such as diabetes, obesity and hypertension, are similar to those associated with poor COVID-19 outcomes. However, the researchers wanted to investigate whether being diagnosed with OSA conferred an additional risk on top of those factors.
The systematic review looked at 18 studies up to June 2020 with regards to OSA and COVID-19. Eight were mainly related to the risk of death from COVID-19 and 10 were related to diagnosis, treatment, and management of sleep apnea. Although few studies of OSA in COVID-19 had been performed at the time, there is evidence to suggest that many patients who presented to intensive care had OSA, and in diabetic patients it may confer an increased risk that is independent of other risk factors. In one large study in patients who had diabetes (who were hospitalized for COVID-19), those being treated for OSA were at 2.8 times greater risk of dying on the seventh day after hospital admission.
Researchers believe that in the UK up to 85% of OSA disorders are undetected, suggesting that the 1.5 million people in the UK currently diagnosed with the condition may be just the tip of the iceberg. With obesity rates and other related risk factors on the increase, the researchers also believe that rates of OSA are also increasing. The review highlights that the pandemic has also had worldwide effects on the ongoing diagnosis, management, and treatment of patients with this and other sleep conditions. Moving forward it may be necessary to explore new diagnosis and treatment pathways for these individuals.
Lead author of the study, Michelle A. Miller, PhD of Warwick Medical School said: “Without a clear picture of how many people have OSA it is difficult to determine exactly how many people with the condition may have experienced worse outcomes due to COVID-19. This condition is greatly underdiagnosed, and we don’t know whether undiagnosed sleep apnea confers an even greater risk or not. It is likely that COVID-19 increases oxidative stress and inflammation and has effects on the bradykinin pathways, all of which are also affected in OSA patients. When you have individuals in which these mechanisms are already affected, it wouldn’t be surprising that COVID-19 affects them more strongly.”
Researchers feel it is important that those diagnosed with OSA are aware of the potential additional risk and are taking appropriate precautions to reduce their exposure to the virus. Further research is required to determine whether these individuals need to be added to the list of vulnerable groups that may need to shield if transmission of virus increases.
Miller added: “This is a group of patients that should be more aware that OSA could be an additional risk if they get COVID-19. Make sure you are compliant with your treatment and take as many precautions as you can to reduce your risk, such as wearing a mask, social distancing and getting tested as soon as you notice any symptoms. Now more than ever is the time to follow your treatment plan as diligently as possible.”