The more severe a patient's obstructive sleep apnea, the
greater their risk of contracting COVID-19, according to research
presented at the ATS 2021 International Conference. The study also
found that the longer patients used positive airway pressure (PAP) each
night, the more they lowered their COVID-19 risk.
Dennis Hwang, MD, medical director KP SBC Sleep Medicine, Kaiser
Permanente and co-chair, sleep medicine, Southern California Permanente
Medical Group, and colleagues examined a database of patients who were
evaluated for sleep disorders by Kaiser Permanente Southern California
between 2015 and 2020. They looked at COVID-19 infection rates and
all-cause hospitalizations and mortality based on obstructive sleep apnea status and whether
patients adhered to PAP therapy.
Obstructive sleep apnea patients who used their positive airway pressure (primarily CPAP) devices for 2 hours or more a night were considered "treated," with increasing
gradations of "treatment" classified for every 2 hours positive airway pressure was used.
The apnea-hypopnea index (AHI) was used to define OSA severity.
Statistical tools were used to calculate the association of various
demographic considerations, such as gender, race/ethnicity, and age, with
The medical records of 81,932 patients were included in the
analysis. 1,493 patients had confirmed COVID-19 infection, with 224
hospitalizations. Sixty-one of the COVID-hospitalized patients were in
the ICU and/or died.
The authors stated, "'Untreated' obstructive sleep apnea (and increasing obstructive sleep apnea severity)
was associated with higher COVID-19 rate and lower rate when 'treated.'
Greater positive airway pressure adherence, when therapy was used at least 4 hours a night
during the pandemic period, also showed a reduced infection rate.
The researchers also conducted an analysis of various factors
that might have affected results. This analysis confirmed a higher
infection rate with obstructive sleep apnea versus no obstructive sleep apnea and the benefit of positive airway pressure (PAP) versus
being "untreated." They also found obesity, higher scores on the
Charlson Comorbidity Index (which classifies patients based on how many
co-occurring chronic illnesses they have), Black or Hispanic ethnicity,
and Medicaid enrollment were also associated with higher COVID-19
Surprisingly, although the elderly are generally more susceptible to
infection with SARS-CoV-2 (the virus that causes COVID-19), increasing
age in the study was associated with reduced infection rate. "We were
also surprised that OSA patients with high adherence with PAP had lower
infection rates than patients who did not even have obstructive sleep apnea," Dr. Hwang
stated. "This further supports a direct physiologic benefit of PAP
"We believe that the relationship between obstructive sleep apnea and higher risk of
COVID-19 infection may be due to both biological and behavioral
factors," said Dr. Hwang. "The higher rate of infection with more
severe obstructive sleep apnea and the shared medical risk factors between obstructive sleep apnea and COVID-19
such as male gender, obesity, and presence of cardiovascular diseases
supports a biological influence, perhaps through impact on respiratory
function, airway inflammation, and sleep fragmentation. On the other
hand, while older age clearly increases COVID-19 severity, our finding
that older age was associated with a reduced infection rate support a
behavioral explanation. Patients with obstructive sleep apnea tend to be older, and older
patients may be more adherent to social distancing, masking, and less
risky social behaviors."
He added, "Likewise, we believe that the relationship between good
positive airway pressure adherence and lower COVID-19 infection rate may also have a direct
biological and indirect behavioral explanation. Reduced upper and lower
airway obstruction, improved lung expansion, improved mobilization of
secretions and positive airway pressure heated humidification may be potential protective
mechanisms. However, the relationship between infection risk and
demographic factors such as increased age, racial/ethnic minority status
and lower economic status suggest that there is a socioeconomic
influence at work."
Dr. Hwang noted that the study was conducted before the severe
winter 2020-2021 COVID surge, when rates of infection spiked. "A
preliminary analysis of an updated dataset suggests that obstructive sleep apnea significantly increased the risk of hospitalization, although the impact
of PAP requires further analysis."
Source: News Release
American Thoracic Society
May 17, 2021