Study reveals obstructive sleep apnoea as risk factor for COVID-19
TURKU, Finland: During the first wave of the pandemic, the number of hospitalisations for SARS-CoV-2 infections in Finland was relatively low compared with the rest of the world, and since hospitals were not overburdened with patients who required intensive care, researchers had the time to examine COVID-19 and its relation to other diseases more closely. For example, researchers from Turku University Hospital and the University of Turku used this time to study the link between COVID-19 and obstructive sleep apnoea (OSA). According to their findings, OSA may be a risk factor for SARS-CoV-2 infection, and patients with OSA may anticipate more severe COVID-19 outcomes if they become infected.
OSA partially or completely obstructs airway flow during sleep, which results in decreased oxygen levels in the blood as well as a temporary cessation in breathing. The disease is marked by excessive daytime sleepiness and loud or frequent snoring, among other things, and various studies have reported that OSA is more prevalent in men than in women and that the chances of developing the disease increase with age and obesity.
According to a study published in The Lancet last year, 936 million adults aged 30–69 years have mild to severe obstructive sleep apnoea (OSA) and 425 million adults aged 30–69 years have moderate to severe OSA globally. According to the same source, the highest OSA prevalence was found in China, the US, Brazil and India, respectively.
As Sleep Foundation.org indicates on its website, since OSA affects oxygen balance in the body, if left untreated, it may increase the risk for various types of cardiovascular issues, such as high blood pressure, heart attack, heart disease and stroke. Interestingly, a recent study has also linked OSA with the disease that swept the world in 2020: COVID-19.
COVID-19 has been the centre of discussion this year. It has been linked with various diseases and has affected people both physically and mentally. Healthy people fear becoming infected with SARS-CoV-2 owing to the uncertainty surrounding the adverse health effects it may have. However, those with underlying medical conditions such as diabetes or inflammatory diseases such as periodontitis are at an increased risk of severe illness from SARS-CoV-2 infection and should take all possible precautions to steer clear of the virus. This adds to mounting pressure and anxiety surrounding the disease.
The present study
According to the study, Southeast Finland saw a total of 278 SARS-CoV-2 infections in spring 2020, during the first wave of the pandemic. Out of these, 28 patients needed intensive care and were hospitalised at Turku University Hospital by 3 May. The researchers then studied the risk factors that contributed to the severe form of COVID-19 and the need for intensive care.
“The idea behind the study was the need for real-time information about COVID-19,” first author Dr Thijs Feuth, a medical doctor in the department of pulmonary diseases at Turku University Hospital, said in a press release. “We quickly observed that there were quite a few cases of sleep apnoea among the patients,” he added.
The findings showed that a staggering 29% of the intensive care patients in the study had been diagnosed with OSA. The number is significant since, according to the researchers, only 3.1% of the total population of Southwest Finland is currently receiving treatment for OSA.
“In principle, a patient may need hospital care when they have a COVID-19 infection if they also have sleep apnoea”
— Dr Thijs Feuth, Turku University Hospital
Although the study sample was small, Feuth commented that the findings justified regarding sleep apnoea as a risk factor for SARS-CoV-2 infection. “In principle, a patient may need hospital care when they have a COVID-19 infection if they also have sleep apnoea. Sleep apnoea anticipates a severe form of COVID-19,” Feuth explained.
Further exploring the link between OSA and COVID-19
Similar studies are under way to further explore the link between the two diseases. It has already been proved that COVID-19 and OSA share comorbidities such as obesity, hypertension and Type 2 diabetes, which are all risk factors for poor clinical outcome in COVID-19 patients. Given these shared comorbidities, a systematic review to be published in February 2021 indicates that it is of paramount importance to ensure that OSA patients receive effective continuous positive airway pressure therapy if they become infected with SARS-CoV-2.
The authors of the systematic review wrote that, in the majority of the studies examined, it was impossible to determine whether OSA is simply a comorbidity that is associated with COVID-19 morbidity and mortality or whether it is an independent risk factor for poor COVID-19 outcomes. “Moving forward, it is necessary that guidelines are reviewed so that, as new knowledge is acquired, the best practices for the diagnosis and treatment of sleep disorders under these restrictive pandemic conditions may be developed,” the review reads.
Although little is known about the connection between OSA and COVID-19, the authors of the review noted that those patients who have been diagnosed with both OSA and COVID-19 but are still awaiting treatment may need priority to mitigate a possible increase in health risk.
The study by researchers from Turku University Hospital and the University of Turku, titled “Is sleep apnea a risk factor for Covid-19? findings from a retrospective cohort study,” was published online on 22 October 2020 in Sleep Medicine and Disorders: International Journal.