Obstructive sleep apnea linked to poor COVID-19 outcomes

Patients with obstructive sleep apnea could have an increased risk for adverse COVID-19 outcomes, according to a systematic review published in Sleep Medicine Reviews.

However, researchers said more studies are needed to determine whether obstructive sleep apnea (OSA) is an independent risk factor or “simply a comorbidity that is associated with COVID-19 morbidity and mortality.”

“There are a number of plausible pathways by which COVID-19 might have an adverse effect on OSA patients and further research is warranted to investigate these pathways,” Michelle A. Miller, PhD, MACadMEd, FBHS, FFPH, FAHA, associate professor in the department of mental health and wellbeing at Warwick Medical School, and Francesco P. Cappuccio, MBBS, MD, MSc (Epid), DSc, DLSHTM, FRCP, FFPH, FBHS, FESC, FAHA, Cephalon Professor of Cardiovascular Medicine and Epidemiology, head of WHO’s Collaborating Centre for Nutrition and director of the European Centre of Excellence in Hypertension and Cardio-Metabolic Research, wrote.

Miller and Cappuccio used the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines to evaluate PubMed search results for studies examining the relationship between COVID-19 and OSA. The authors included 18 studies with full-text availability that were published in English on or before June 2, and addressed one of the following outcomes: how OSA is related to adverse outcomes for COVID-19, the effect of COVID-19 on diagnosing, treating and managing OSA, and biological mechanisms. They included 15 studies on the biological mechanisms.

The researchers found that OSA shares risk factors and comorbidities associated with negative COVID-19 outcomes, including obesity, hypertension, diabetes and idiopathic pulmonary fibrosis. They cited the recent CORONADO study that revealed patients with OSA who were hospitalized for COVID-19 had an increased risk for mortality on day 7 of admission (OR = 2.80). The researchers also found “plausible mechanisms” for OSA to independently increase a patient’s risk for morbidity and mortality, including obesity — which may worsen hypoxemia and cytokine storm worse — and low vitamin D levels.

Other research indicates that the sleep hormone melatonin may benefit patients with COVID-19, according to the researchers. Melatonin, they said, may reduce the “oxidative stress, inflammation and the immune response” in patients with OSA. It could also improve sleep quality, which Miller and Cappuccio said can improve COVID-19 outcomes.

In the literature, there was mixed evidence on whether patients should discontinue continuous positive airway pressure or non-invasive ventilation treatments because they generate aerosols. Researchers are designing filters to reduce the risk for viral shedding through positive airway devices, according to Miller and Capuucio. Another study indicated that an Enhanced Expiratory Rebreathing Space filter could help reduce viral shedding. However, researchers said that patients with severe OSA who contract COVID-19 “might be best managed in a health care facility where staff might be able to take necessary precautions and use personal protective equipment.”

Despite the potential increased risk for COVID-19 in patients with OSA, pandemic response efforts have disrupted OSA diagnosis on a global basis, the researchers wrote.

“Moving forward, it may be necessary to explore new diagnosis and treatment pathways for these individuals,” they added. “This may include the increased telemedicine and the use of disposable diagnostic tools and noncontact sleep surveillance for sleep apnea diagnosis. Those already diagnosed but awaiting treatment may need priority at this time to mitigate any potential increase in risk.”