{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,26]],"date-time":"2026-09-26T12:37:49Z","timestamp":1790426269900,"version":"4.1.0"},"reference-count":38,"publisher":"BMJ","issue":"12","license":[{"start":{"date-parts":[[2021,12,11]],"date-time":"2021-12-11T00:00:00Z","timestamp":1639180800000},"content-version":"unspecified","delay-in-days":10,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["BMJ Open"],"accepted":{"date-parts":[[2021,11,17]]},"published-print":{"date-parts":[[2021,12]]},"abstract":"<jats:sec>\n                    <jats:title>Objectives<\/jats:title>\n                    <jats:p>Sleep is important for human health and well-being. No previous study has assessed whether the COVID-19 pandemic impacts sleep and daytime function across the globe.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>This large-scale international survey used a harmonised questionnaire. Fourteen countries participated during the period of May\u2013August 2020. Sleep and daytime problems (poor sleep quality, sleep onset and maintenance problems, nightmares, hypnotic use, fatigue and excessive sleepiness) occurring \u2018before\u2019 and \u2018during\u2019 the pandemic were investigated. In total, 25\u2009484 people participated and 22\u2009151 (86.9%) responded to the key parameters and were included. Effects of COVID-19, confinement and financial suffering were considered. In the fully adjusted logistic regression models, results (weighted and stratified by country) were adjusted for gender, age, marital status, educational level, ethnicity, presence of sleep problems before COVID-19 and severity of the COVID-19 pandemic in each country at the time of the survey.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>The responders were mostly women (64%) with a mean age 41.8 (SD 15.9) years (median 39, range 18\u201395). Altogether, 3.0% reported having had COVID-19; 42.2% reported having been in confinement; and 55.9% had suffered financially. All sleep and daytime problems worsened during the pandemic by about 10% or more. Also, some participants reported improvements in sleep and daytime function. For example, sleep quality worsened in about 20% of subjects and improved in about 5%. COVID-19 was particularly associated with poor sleep quality, early morning awakening and daytime sleepiness. Confinement was associated with poor sleep quality, problems falling asleep and decreased use of hypnotics. Financial suffering was associated with all sleep and daytime problems, including nightmares and fatigue, even in the fully adjusted logistic regression models.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Sleep problems, fatigue and excessive sleepiness increased significantly worldwide during the first phase of the COVID-19 pandemic. Problems were associated with confinement and especially with financial suffering.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1136\/bmjopen-2021-050672","type":"journal-article","created":{"date-parts":[[2021,12,13]],"date-time":"2021-12-13T11:32:14Z","timestamp":1639395134000},"page":"e050672","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":63,"title":["Sleep and daytime problems during the COVID-19 pandemic and effects of coronavirus infection, confinement and financial suffering: a multinational survey using a harmonised questionnaire"],"prefix":"10.1136","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8182-9368","authenticated-orcid":false,"given":"Markku","family":"Partinen","sequence":"first","affiliation":[{"name":"Department of Clinical Neurosciences, University of Helsinki Clinicum Unit, Helsinki, Finland"},{"name":"Helsinki Sleep Clinic, Terveystalo Healthcare Services, Helsinki, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Brigitte","family":"Holzinger","sequence":"additional","affiliation":[{"name":"Institute for Dream and Consciousness Research, Medical University of Vienna, Wien, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Charles M","family":"Morin","sequence":"additional","affiliation":[{"name":"Centre d\u2019\u00e9tude des troubles du sommeil, Centre de recherche CERVO\/Brain Research Center, Universit\u00e9 Laval \u00c9cole de psychologie, Quebec, Quebec, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Colin","family":"Espie","sequence":"additional","affiliation":[{"name":"Sleep and Circadian Neuroscience Institute, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9576-3606","authenticated-orcid":false,"given":"Frances","family":"Chung","sequence":"additional","affiliation":[{"name":"Department of Anesthesiology and Pain Medicine, University Health Network, Toronto, Ontario, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4304-0112","authenticated-orcid":false,"given":"Thomas","family":"Penzel","sequence":"additional","affiliation":[{"name":"Sleep Medicine Center, Charite University Hospital Berlin, Berlin, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christian","family":"Benedict","sequence":"additional","affiliation":[{"name":"Department of Neuroscience, Sleep Science (BMC), Uppsala University, Uppsala, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Courtney J","family":"Bolstad","sequence":"additional","affiliation":[{"name":"Department of Psychology, Mississippi State University, Mississippi State, Mississippi, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jonathan","family":"Cedernaes","sequence":"additional","affiliation":[{"name":"Department of Medical Sciences, Uppsala University, Uppsala, Sweden"},{"name":"Department of Medicine, Division of Endocrinology, Metabolism, and Molecular Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rachel Ngan Yin","family":"Chan","sequence":"additional","affiliation":[{"name":"Li Chiu Kong Family Sleep Assessment Unit, Department of Psychiatry, The Chinese University of Hong Kong, Hong Kong, Hong Kong"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yves","family":"Dauvilliers","sequence":"additional","affiliation":[{"name":"National Reference Center for Narcolepsy, Sleep and Wake Unit, Department of Neurology, Gui-de-Chauliac Hospital, 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