Data from a systemic review suggests that the COVID-19 pandemic is associated with increased rates of subthreshold insomnia symptoms, but not with moderate or severe insomnia, among the global population.
A recent global systematic review and individual participant data meta-analysis implied in its findings that the COVID-19 pandemic is linked to a significant increase in subthreshold of insomnia symptoms, although not for moderate or severe insomnia.1
Previously, there had not been any meta-analytic studies conducted which focused on the prevalence of insomnia symptoms in different COVID-19 patient groups. This review was able to evaluate insomnia symptoms while maintaining data homogeneity by using a single assessment instrument.
From the pooled analysis, the estimate of insomnia symptoms, both subthreshold and clinically significant, was 52.57%. There was an estimate of 16.66% that suffered from clinically significant insomnia, where 13.75% of that population suffered from moderate insomnia, and 2.50% suffered from severe insomnia.1 Maha Meshal Alrasheed, PhD, MSc associate professor, Clinical Pharmacy Department, College of Pharmacy, King Saud University, and colleagues that their data, “suggests that the COVID-19 pandemic is associated specifically with a marked increase in the rates of subthreshold insomnia symptoms but not moderate or severe insomnia.”
Seventeen databases and 6 preprint services of relevant studies between November 2019 and August 2021 were explored. Included in the analysis were only studies that assessed insomnia using the Insomnia Severity Index (ISI). Overall, the systematic review collected 48 studies from 25 countries and 133,006 participants from the studies were assessed with ISI for insomnia symptoms during the COVID-19 pandemic.
Alrasheed and colleagues wrote that, “a statistically significant difference was observed between countries for all severities of insomnia symptoms. Neither age nor sex appeared to be moderators of the prevalence of cumulative prevalence of subthreshold insomnia symptoms or of clinically significant insomnia.” All told, the different rates of subthreshold insomnia symptoms in the various countries included were 27.27% in China (95% CI, 22.30-32.88), 28.91% in India (95% CI, 24.90-33.28), 46.82% in Italy (95% CI, 38.24-55.61), 35.11% in Turkey (95% CI, 32.45-37.86), and 38.31% in the United States (95% CI, 28.54-49.13).1
This study is consistent with 2 other prior meta-analyses on the pooled prevalence rate of insomnia symptoms observed during COVID-19 (40%-50%).2,3 Many factors could have contributed to the increase in insomnia symptoms caused by the COVID-19 pandemic, including high levels of anxiety, depression, posttraumatic stress disorder, and stress were reported by the general population worldwide as the COVID-19 pandemic took place.4 Other factors reported as important were being a woman, in a younger age group, having a history of psychiatric illnesses, unemployment, low educational status, and frequent exposure to social media/news regarding the pandemic.4
Alrasheed et al’s study's strengths were that the prevalence of insomnia symptoms, by severity, was estimated in different populations using individual participants' data. Hence, this provided a more accurate understanding of insomnia symptoms from effects of COVID-19. Notably, the meta-regression and subgroup analysis provided an effective approach for the findings in exploring heterogeneity. The synthesized sample size was large as participants were recruited from 25 countries, which makes the findings generalizable.
The limitations of the study included that there might have been bias in the estimations of prevalence of insomnia as other measures could have captured insomnia severity in a different way. Another limitation is that the estimated results do not necessarily reflect COVID-19's impact over a specific period and are not generalizable to various ethnic and age groups. In addition, the review’s response rate was a limitation as only approximately 50% of authors agreed to participate with providing the original datasets for secondary analyses.1
Alrasheed et al noted, “Educating diverse demographic groups about the significance of sleep and the risk of developing symptoms of insomnia during this or future pandemics should be a concern for the sleep medicine community, as should be developing measures to prevent the development of subthreshold insomnia and from its progression to more severe forms of the disorder.”