Poor sleep quality, insomnia, and short sleep duration before infection predict long-term symptoms after COVID-19

Study objectives Millions of COVID-19 survivors experience a wide range of long-term symptoms after acute infection, giving rise to serious public health concerns. To date, few risk factors for post-COVID-19 conditions have been determined. This study evaluated the role of pre-infection sleep quality/duration and insomnia severity in the incidence of long-term symptoms after COVID-19. Methods This prospective study involved two assessments (April 2020 and 2022). At baseline, sleep quality/duration and insomnia symptoms in participants without current/prior SARS-CoV-2 infection were measured using the Pittsburgh Sleep Quality Index (PSQI) and the Insomnia Severity Index (ISI). At follow-up, we evaluated the presence of twenty-one symptoms (psychiatric, neurological, cognitive, bodily, and respiratory) one month (n=713, infection in April 2020–February 2022) and three months after COVID-19 (n=333, infection in April 2020–December 2021). Zero-inflated negative binomial models were used to estimate the effect of previous sleep on the number of long-term symptoms. Binomial logistic regressions were performed to evaluate the association between sleep outcomes and the incidence of each post-COVID-19 symptom. Results Analyses highlighted a significant effect of pre-infection sleep on the number of symptoms one/three months after COVID-19. Previous higher PSQI and ISI scores, and shorter sleep duration significantly increased the risk of almost every long-term symptom at one/three months from COVID-19. Conclusion This study suggested a prospective dose-dependent association between pre-infection sleep quality/quantity and insomnia severity with the manifestation of post-COVID-19 symptoms. Promoting sleep health may represent an effective preventive approach to mitigate the COVID-19 sequelae, with substantial public health and societal implications. Statement of significance Determining potential risk factors of long COVID is crucial to driving preventive interventions amongst vulnerable populations. The present study is the first to provide insights into the role of pre-infection sleep disturbances in the occurrence of post-COVID-19 conditions. We demonstrated a strong association between previous sleep quality/duration and insomnia severity with the incidence of a broad spectrum of long-term symptoms one and three months after COVID-19. These results may have large-scale implications, considering the alarming rates of both sleep disturbances and post-COVID-19 manifestations worldwide. Further research is warranted to determine the biobehavioral mechanisms involved. Future studies should also evaluate whether treating sleep problems may improve the subsequent long-term consequences of COVID-19. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement This study did not receive any funding ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: Institutional Review Board of the University of L Aquila gave ethical approval for this work (protocol no. 43066). I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines and uploaded the relevant EQUATOR Network research reporting checklist(s) and other pertinent material as supplementary files, if applicable. Yes The data underlying this article will be shared on reasonable request to the corresponding author.