Was there a significant difference in sleep shifts in the high school population due to the COVID-19 pandemic depending on chronotype? A nationwide cross-sectional study

ABSTRACT

The aim of this study was to detect whether the COVID-19 pandemic has caused changes in the sleep cycle (subjective sleep shifts) of high school students divided into a sample of young women – W (n = 1999, age = 17.65 ± 2.39 y) and young men – M (n = 1094, age = 17.49 ± 1.74 y) in Slovakia depending on circadian preference in comparison with the term before COVID-19. The present cross-sectional study employed a self-reported standardized questionnaire (Morningness-Eveningness Questionnaire) to study circadian preference, which was complemented by a question focused on subjective sleep shifts before and during the pandemic. The results revealed significant strong dependence between circadian preference and subjective sleep shift in both W (χ²₍₈₎ = 153.1, p < .01, Cramer’s V = .20, p < .01) and M (χ²₍₈₎ = 98.3, p < .01, Cramer’s V =.21, p < .01). The delay of the sleep cycle has mainly become apparent in the case of definite evening types (W: 75.7%; M: 71.8%) and moderate evening types (W: 83.1%; M: 70.3%). The delay also prevailed in the intermediate types (W: 61.9%; M: 53.8%). Subjective sleep shifts were not confirmed (W: 93.8%; M: 35.3%) in the definite morning type. The sleep cycle was changed to earlier hours of definite morning types (W: 6.3%; M: 52.9%). It is necessary to focus on definite and moderate evening types and regulate the unsuitable state to time shift of the sleep cycle.

KEYWORDS:

• Circadian preference
• COVID-19 pandemic
• Morningness-Eveningness Questionnaire
• adolescence
• sleep-wake behaviour

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

That that support the findings of this study are openly available in Harvard Dataverse at https://doi.org/10.7910/DVN/2BZXLZ.

Additional information

Funding

This project was supported by UNCE HUM32 and Cooperation: Sport Sciences BM&R Medicine.