Obstructive sleep apnea phenotypes in patients with a history of COVID-19 infection

The COVID-19 pandemic has had an impact on health systems worldwide. Patients with Long-COVID present many symptoms, particularly fatigue. An association between COVID-19 and obstructive sleep apnea (OSA) has been reported in the literature. In this context, understanding the incidence and phenotypic characteristics of OSA in patients with a history of COVID-19 infection is important for the management of treatment strategies for both OSA and Long- COVID. This research was a case-control study conducted at Koç University Hospital. The case group consisted of individuals who had a COVID-19 infection (n=152) and the control group consisted of individuals who had previously applied to the sleep laboratory and did not have a history of COVID-19 infection (n=152). Both groups were matched for age, gender and body mass index. The prevalence of OSA; defıned as an apnea-hypopnoea index [AHI] ≥15/hour) was significantly lower in the case group (50.0%) compared to the control group (77.6%) (p<0.001). However, 36 cases (47.4%) exhibited REM-predominant OSA (defined as a total AHI of ≥15/hour and REM-AHI /non-REM-AHI ≥2), while only 21 controls (17.8%) demonstrated this phenotype (p<0.001). In a multiple logistic regression analysis, there was a significant correlation between a history of COVID-19 and the occurrence of REM-predominant OSA (Odds ratio [OR] 3.14; 95% confidence interval [CI] 1.89-5.25; p<0.001). The Fatigue, reported as "frequent/very frequent," was observed in 52.8% of patients with REM-predominant OSA and 35.7% of patients without REM-predominant OSA (p=0.033). In the entire cohort, the factors determining the fatigue were found to be female sex (OR 2.02; 95% CI 1.12-3.64, p=0.019) and REM-predominant OSA (OR 2.18; 95% CI 1.29-3.69; p=0.004). Our results suggest that REM-predominant OSA is very common among individuals with a history of COVID-19 infection, which is significantly associated with fatigue. Thus, it is important to consider REM-predominant OSA in individuals with Long-COVID to better manage both conditions.