Insomnia, Hypersomnia Identified as Symptoms of Long COVID Syndrome

Alissa Elen Formiga Moura

Up to 32% of patients who have been infected with COVID-19 are affected by long-onset COVID syndrome. Patients with the syndrome experience symptoms that persist for more than 4 weeks post infection, or the development of sequelae.

Some symptoms that have been associated with long COVID include fatigue, dyspnea, chest pain, cognitive disorders, insomnia, and psychiatric disorders. This study honed in on the symptoms related to sleep that these patients encounter.

Alissa Elen Formiga Moura, Hospital Universitário Walter Cantídio, Neurology Service, Universidade Federal do Ceará, Fortaleza, Brazil, and a team of investigators aimed to characterize and evaluate the prevalence of sleep symptoms through clinical evaluation with a neurologist.

Does COVID-19 Infection Impact Sleep?

The prospective cohort study initially included 207 patients with post-COVID symptoms, and 189 of them completed the study. In addition to a neurological evaluation to assess the presence of sleep disorders, a more extensive analysis was performed on the subgroup that reported excessive sleepiness.

Evaluations took place at a neurology outpatient clinic in Hospital Universitário Walter Cantídio – Universidade Federal do Ceará in the state of Ceará, northeast Brazil, and occurred between August 2020-September 2021.

In order to factor in the prevalence of insomnia in the general population, which was estimated at 10%, investigators calculated the sample size to discern differences that were statistically significant. According to the team, this resulted in a total of N = 139 patients; after which, a dropout of 25% was stipulated to compose the final sample, totaling a minimum sample size of 186 patients.

The Spectrum of Sleep Disorders in Long COVID

Results revealed the presence of sleep-related symptoms in 25.3% of patients in the long COVID sample. The marjority of the subgroup (22.2%) reported insomnia, while the remaining 6 (3.17%) reported excessive sleepiness.

Of those who were experiencing excessive sleepiness, 4 patients underwent a polysomnography evaluation, multiple sleep latencies test, and actigraphic data. According to the results, 1 patient had narcolepsy, and 2 patients had central hypersomnia.

Additionally, investigators found that patients with a history of steroid use demonstrated an association with insomnia and excessive sleepiness. The latter was also related to depression. The team acknowledged a high prevalence of cognitive complaints from patients.

"Complaints related to sleep, such as insomnia and excessive sleepiness, seem to be part of the clinical post-acute syndrome (long COVID syndrome), composing part of its clinical spectrum, relating to some clinical data," investigators wrote.

The study "Central hypersomnia and chronic insomnia: expanding the spectrum of sleep disorders in long COVID syndrome - a prospective cohort study" was published in BMC Neurology.