University of Oulu

Ong, J.L., Lau, T., Karsikas, M. et al. A longitudinal analysis of COVID-19 lockdown stringency on sleep and resting heart rate measures across 20 countries. Sci Rep 11, 14413 (2021).

A longitudinal analysis of COVID-19 lockdown stringency on sleep and resting heart rate measures across 20 countries

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Author: Ong, Ju Lynn1; Lau, TeYang1; Karsikas, Mari2,3;
Organizations: 1Centre for Sleep and Cognition, Human Potential Program, Yong Loo Lin School of Medicine, National University of Singapore, 12 Science Drive 2, Singapore, 117549, Singapore
2Oura Health, Oulu, Finland
3Centre for Life Course Health Research, University of Oulu, Oulu, Finland
Format: article
Version: published version
Access: open
Online Access: PDF Full Text (PDF, 5.2 MB)
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Language: English
Published: Springer Nature, 2021
Publish Date: 2021-10-15


Lockdowns imposed to stem the spread of COVID-19 massively disrupted the daily routines of many worldwide, but studies to date have been mostly confined to observations within a limited number of countries, based on subjective reports and surveys from specific time periods during the pandemic. We investigated associations between lockdown stringency and objective sleep and resting-heart rate measures in ~ 113,000 users of a consumer sleep tracker across 20 countries from Jan to Jul 2020, compared to an equivalent period in 2019. With stricter lockdown measures, midsleep times were universally delayed, particularly on weekdays, while midsleep variability and resting heart rate declined. These shifts (midsleep: + 0.09 to + 0.58 h; midsleep variability: − 0.12 to − 0.26 h; resting heart rate: − 0.35 to − 2.08 bpm) correlated with the severity of lockdown across different countries (all Ps < 0.001) and highlight the graded influence of stringency lockdowns on human physiology.

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Series: Scientific reports
ISSN: 2045-2322
ISSN-E: 2045-2322
ISSN-L: 2045-2322
Volume: 11
Article number: 14413
DOI: 10.1038/s41598-021-93924-z
Type of Publication: A1 Journal article – refereed
Field of Science: 3142 Public health care science, environmental and occupational health
Funding: Work conducted at the National University of Singapore is supported by a Grant awarded to Michael Chee from the National Medical Research Council Singapore (STAR19may-0001).
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