Persistent sleep symptoms in post-COVID syndrome: a Brazilian prospective clinical study

Post coronavirus disease (COVID) syndrome is a frequent condition, resulting from the persistence of symptoms or the development of new ones, after 12 weeks of acute severe acute respiratory syndrome coronavirus 2 infection. The impact on sleep was observed worldwide, whether in the acute phase due to the direct effect of the infection or due to changes in patients' circadian cycle imposed by new routines during quarantine, dysfunctional habits, and social isolation.Given the persistence of sleep-related symptoms in patients with long-term COVID syndrome, we decided to follow-up and reassess these patients after 1 year.The present is an observational, longitudinal, and prospective clinical study. The study took place in two stages: the first assessment between October 2020 and September 2021, with reassessment after 1 year. Participants underwent the application of the Geriatric Depression Scale (GDS) or the Beck Inventory, Addenbrooke's Cognitive Examination - Revised (ACE-R) and Mini-Mental State Examination (MMSE). The evaluation of sleep disorders involved a comprehensive clinical history obtained through a structured questionnaire.Of the 46 cases with sleep complaints, 7 refused to return for a new assessment. Thus, 39 patients were included, of which 9 persisted with insomnia (23.07%) and 2 patients persisted with central hypersomnia (5.12%). The persistence of cognitive complaints was also higher in patients with insomnia when compared with those without it (N = 5; 56%, p = 0.001).Given the persistence of patients with insomnia and central hypersomnia, the damage to the central nervous system may be lasting, reinforcing the need for follow-up.