Circadian rhythm disorder and anxiety as mental health complications in post-COVID-19

In 2020, the world gained dramatic experience of the development of the 2019 coronavirus disease pandemic (COVID-19) caused by severe acute respiratory syndrome 2 (SARS-CoV-2). Recent researches notice an increasing prevalence of anxiety and circadian rhythm disorders during COVID-19 pandemic. The aim of the study was describing clinical features of circadian rhythm disorders and the level of anxiety in persons who have had COVID-19. We have conducted a cohort retrospective study that included 278 patients who were divided into 2 study groups according to medical history: group 1 includes patients with a history of COVID-19; group 2 consists of patients who did not have clinically confirmed COVID-19 and are therefore considered not to have had this disease. To objectify circadian rhythm disorders, they were verified in accordance with the criteria of the International Classification of Sleep Disorders-3. The level of anxiety was assessed by the State-Trait Anxiety Inventory. The most common circadian rhythm disorders were sleep phase shifts. We found that COVID-19 in the anamnesis caused a greater predisposition of patients to the development of circadian rhythm disorders, in particular delayed sleep phase disorder. In addition, it was found that after COVID-19 patients have increased levels of both trait and state anxiety. In our study, it was the first time that relationships between post-COVID-19 anxiety and circadian rhythm disorders had been indicated. Circadian rhythm disorders are associated with increased trait and state anxiety, which may indicate additional ways to correct post-COVID mental disorders and their comorbidity with sleep disorders.