The impact of the lockdown in response to the coronavirus-19 (COVID-19) pandemic on sleep quality varies across individuals and depends on their pre-pandemic sleep quality, according to results of a study published in Sleep Medicine.

Though studies have demonstrated that the COVID-19 pandemic has significantly affected sleep duration across different populations, the impact on sleep quality and particularly individuals with poor sleep quality before the pandemic has not yet been determined.

To assess this, weekly sleep and mood log data from 667 individuals were analyzed. Participants completed the Insomnia Severity Index, which qualifies sleep quality on a range of 0-28. Prior to the pandemic, 33.1% of participants had good sleep quality (ISI scores ≤7), 34.9% had mild sleep complaints (ISI scores 8-14), and 31.9% had clinical insomnia (ISI scores 15-28). A change of ≥6 in ISI score was considered meaningful.

Meaningful change was observed in 25.3% of participants. Of individuals who previously had good sleep quality and experienced a change in sleep quality during the pandemic, the majority experienced a decrease in sleep quality. Of the individuals who had clinical insomnia before the pandemic, 25% experienced a meaningful change. Of the individuals with insomnia before the pandemic who experienced a meaningful change, 86.9% reported an improvement in sleep quality.

Limitations to this study include its self-reporting design and reliance on retrospective pre-pandemic sleep quality data. Another limitation is that individuals with very high or very low ISI scores before the pandemic could only meaningfully change in the opposite direction. Future research investigating potential treatments to improve sleep quality in the context of the COVID-19 pandemic are warranted.

The results of this study showed that the effect of the lockdown on perceived sleep quality varied by the sleep quality prior to the pandemic. While the pandemic has generally been shown to have had a negative impact on mental health, a meaningful improvement in the sleep quality of individuals who had insomnia before the pandemic was observed.

Reference

Kocevska D, Blanken TF, Van Someren EJW, Rösler L. Sleep quality during the COVID-19 pandemic: not one size fits all. [published online October 8, 2020]. Sleep Med. doi: 10.1016/j.sleep.2020.09.029