COVID-19 and Long COVID Impact Sleep Disturbances

In a new study published in eClinicalMedicine, researchers looked at how pre-existing sleep disorders affected coronavirus disease 2019 (COVID-19) susceptibility, severity, and long-term repercussions.

The study discovered that pre-existing sleep disorders increased the likelihood of susceptibility to COVID-19, as well as hospitalization, death, and protracted COVID, with age and gender playing a role.

Background

The COVID-19 pandemic has resulted in enormous global morbidity and mortality, with protracted COVID becoming a major concern, affecting at least 65 million people globally.

Long COVID comprises a variety of symptoms and new-onset disorders, resulting in persistent health and economic difficulties. Sleep disorders, such as insomnia and obstructive sleep apnea (OSA), were common during the pandemic, affecting 40.49% of the worldwide population. These disorders are known to be associated with immunological weakness and inflammation, worsening the effects of COVID-19.

While prior research has indicated that OSA enhances the severity and mortality rate of COVID-19, other sleep disorders and their impact in long-term COVID are less well understood.

There is conflicting information about the relationship between sleep problems and prolonged COVID, with some research finding a favorable association between conditions such as OSA and insomnia, while others find no significant link.

Comprehensive study is required to understand these linkages and adequately address long-term COVID. As a result, researchers in the current meta-analysis sought to investigate the impact of pre-existing sleep disorders on COVID-19 outcomes.

About the study

A total of 48 relevant observational studies with 8,664,026 individuals were retrieved from sources such as Web of Science, PubMed, and Embase. The studies looked at COVID-19 susceptibility (22), hospitalization (12), death (16), and extended COVID (11).

Case reports, brief communications, letters, reviews, and preprints were all omitted. The majority of studies were undertaken in the United States, with men accounting for up to 72% of the participants. The investigations focused on four types of sleep disturbances: OSA, insomnia, irregular sleep length, and night shift work.

Two researchers extracted and analyzed data. They gathered basic data (author, year, study design, region, sample size, age, gender), categories of sleep disorders, and COVID-19 results.

Odds ratios (ORs) were estimated using existing data or alternative ratios if needed. Quality was assessed using the Agency for Healthcare Research and Quality for cross-sectional studies and the Newcastle-Ottawa Scale for cohort/case-control studies.

Pooled odds ratios, heterogeneity assessment, subgroup analysis, sensitivity analyses, Egger’s test, and the trim-and-fill approach were used to assess publication bias.

Results and discussion

Participants with pre-existing sleep problems were more vulnerable to COVID-19 (OR = 1.12). Specific disorders such as OSA, irregular sleep duration, and night shift employment all increased COVID-19 occurrence.

Low- and middle-income nations showed higher susceptibility than high-income countries, as did studies with unadjusted ORs. Younger people with sleep difficulties had a higher risk (OR = 1.20), but older people did not.

Furthermore, patients who had pre-existing sleep disorders were more likely to be hospitalized for COVID-19 (OR = 1.25), with all sleep disturbances except insomnia contributing to this elevated risk. Patients under the age of 60 showed a stronger connection.

Pre-existing sleep disorders were also linked to an increase in COVID-19 mortality (OR = 1.45), primarily due to OSA. This risk was higher in older individuals and males. Diabetes was discovered to be a substantial source of heterogeneity, with a greater link between sleep disruptions and COVID-19 mortality in diabetic patients than in the overall population.

Furthermore, pre-existing sleep problems significantly enhanced the likelihood of acquiring a prolonged COVID (OR = 1.36). Long COVID, defined as symptoms lasting ≥3 months, had a stronger connection than ≥1 month.

Subgroup analysis indicated that OSA increased long-term COVID risk in both definitions (3-month OR = 1.75; 1-month OR = 1.12). Thus, OSA may be a risk factor for long-term COVID, although more study is needed to corroborate these findings.

Asymmetric funnel plots revealed probable publication bias in COVID-19 susceptibility, hospitalization, and death studies. The subgroup and sensitivity analyses supported the overall findings, indicating the study’s robustness.

The study emphasizes the need of including sleep disruptions in COVID-19 management and prevention measures. This is the first meta-analysis to look at the effect of all sleep disruptions (not just OSA) on the overall clinical course of COVID-19. However, the study’s limitations include the significant heterogeneity of outcomes, the observational character of all included research, and the inability to demonstrate causal links.

Conclusion

In conclusion, sleep disruptions, particularly OSA, significantly increased the chances of COVID-19 susceptibility, hospitalization, death, and prolonged COVID, with these effects modulated by age and gender.

As a result, the study encourages healthcare practitioners to undertake early assessments and timely management for individuals experiencing sleep difficulties in order to mitigate the immediate and long-term effects of COVID-19.

For more information: Zhou, Jiawei et al., (2024) Pre-existing sleep disturbances and risk of COVID-19: a meta-analysis. eClinicalMedicine, Volume 74, 102719. doi: 10.1016/j.eclinm.2024.102719. https://www.thelancet.com/journals/eclinm/article/PIIS2589-5370(24)00298-0/fulltext