Persistent olfactory dysfunction associated with poor sleep quality and anxiety in patients with long COVID

Abstract

IntroductionPoor sleep quality have been widely reported in patients with long COVID. Determining the characteristics, type, severity, and relationship of long COVID with other neurological symptoms is essential for the prognosis and management of poor sleep quality.MethodsThis cross-sectional study was conducted at a public university in the eastern Amazon region of Brazil between November 2020 and October 2022. The study involved 288 patients with long COVID with self-report neurological symptoms. One hundred thirty-one patients were evaluated by using standardised protocols: Pittsburgh sleep quality index (PSQI), Beck Anxiety Inventory, Chemosensory Clinical Research Center (CCRC), and Montreal Cognitive Assessment (MoCA). This study aimed to describe the sociodemographic and clinical characteristics of patients with long COVID with poor sleep quality and their relationship with other neurological symptoms (anxiety, cognitive impairment, and olfactory disorder).ResultsPatients with poor sleep quality were mainly women (76.3%), 44.04 ± 12.73 years old, with >12 years of education (93.1%), and had monthly incomes of up to US $240.00 (54.2%). Anxiety and olfactory disorder were more common in patients with poor sleep quality.DiscussionMultivariate analysis shows that the prevalence of poor sleep quality was higher in patients with anxiety, and olfactory disorder is associated with poor sleep quality. In this cohort of patients with long COVID, the prevalence of poor sleep quality was highest in the group tested by PSQI and were associated with other neurological symptoms, such as anxiety and olfactory dysfunction. A previous study indicates a significant association between poor sleep quality and psychological disorders over time. Recent studies involving neuroimaging found functional and structural changes in Long COVID patients with persistent olfactory disfunction. Poor sleep quality are integral part of complex changes related to Long COVID and should be part of patient’s clinical management.

Poor sleep quality may trigger cognitive deficits after recovery from COVID-19

“…Similar results were described by Bolattürk and Soylu (2023) in a sample of forty PCC participants, where the PSQI score did not correlate with the MoCA or MMSE score; instead, the MoCA score correlated with the Hamilton Depression Scale score. More examples of the relationship between sleep quality and other variables, such as anxiety, can be found in this study, which also analysed olfactory dysfunction in patients with long COVID ( Paranhos et al, 2023 ). The authors did not find an association between sleep quality and cognition (measured with the MoCA).…”

Effect of long COVID-19 syndrome on health-related quality of life: a cross-sectional study

“…A recent cross-sectional study published by our group of 288 patients with long COVID showed that the presence of anxiety is a risk factor for poor sleep quality, and that patients with sleep disorders more frequently report symptoms of anxiety ( Paranhos et al, 2023 ). Anxiety and insomnia have common pathophysiological mechanisms.…”

fNIRS a novel neuroimaging tool to investigate olfaction, olfactory imagery, and crossmodal interactions: a systematic review

“…Different odours have been demonstrated to modulate mood, and feelings of stress and anxiety ( Lehrner et al, 2000 ; Fukada et al, 2011 ; Kaimal et al, 2020 ). During and following the years of COVID-19 infection the impact to olfaction due to infection complications became a significant metric for long-COVID effects ( Kapoor et al, 2021 ; Tan et al, 2022 ; Paranhos et al, 2023 ). Further research could advise applications of olfaction interventions in health and wellbeing.…”