Skip to main content
Oxford University Press - PMC COVID-19 Collection logoLink to Oxford University Press - PMC COVID-19 Collection
. 2021 May 12:afab103. doi: 10.1093/ageing/afab103

Prevalence, incidence and mortality of delirium in patients with COVID-19: A systematic review and meta-analysis

Shih-Chieh Shao 1,2, Chien-Cheng Lai 3, Yi-Hung Chen 4, Yung-Chang Chen 5,6, Ming-Jui Hung 7,8, Shu-Chen Liao 9,10,
PMCID: PMC8247209  PMID: 33984129

Abstract

Background: Attention should be paid to delirium in COVID-19 patients, especially older people, since advanced age poses increased risk of both delirium and COVID-19-related death.

Objective: This study aims to summarize the evidence on prevalence, incidence and mortality of delirium in COVID-19 patients.

Methods: We conducted a comprehensive literature search on Pubmed and Embase from inception to December 1, 2020. Three independent reviewers evaluated study eligibility and data extraction, and assessed study quality. Outcomes were analyzed as proportions with 95% confidence interval (CI). We also compared mortality differences in COVID-19 patients using odds ratio.

Results: In total, we identified 48 studies with 11,553 COVID-19 patients from 13 countries. Pooled prevalence, incidence and mortality rates for delirium in COVID-19 patients were 24.3% (95% CI: 19.4–29.6%), 32.4% (95% CI: 20.8–45.2%) and 44.5% (95% CI: 36.1–53.0%), respectively. For patients aged over 65 yrs, prevalence, incidence and mortality rates for delirium in COVID-19 patients were 28.2% (95% CI: 23.5–33.1%), 25.2% (95% CI: 16.0–35.6%) and 48.4% (95% CI: 40.6–56.1%), respectively. For patients under 65 yrs, prevalence, incidence and mortality rates for delirium in COVID-19 patients were 15.7% (95% CI: 9.2–23.6%), 71.4% (95% CI: 58.5–82.7%) and 21.2% (95% CI: 15.4–27.6%), respectively. Overall, COVID-19 patients with delirium suffered higher risk of mortality, compared to those without delirium (OR: 3.2, 95% CI: 2.1–4.8).

Conclusion: Delirium developed in almost 1 out of 3 COVID-19 patients, and was associated with 3-fold overall mortality. Our findings suggest that first-line healthcare providers should systematically assess delirium and monitor related symptoms among COVID-19 patients.

Keywords: COVID-19, delirium, prevalence, incidence, mortality, meta-analysis

Contributor Information

Shih-Chieh Shao, Department of Pharmacy, Keelung Chang Gung Memorial Hospital, Keelung, Taiwan; School of Pharmacy, Institute of Clinical Pharmacy and Pharmaceutical Sciences, College of Medicine, National Cheng Kung University.

Chien-Cheng Lai, Department of Traditional Chinese Medicine, Keelung Chang Gung Memorial Hospital, Taiwan.

Yi-Hung Chen, Department of Pharmacy, Keelung Chang Gung Memorial Hospital, Keelung, Taiwan.

Yung-Chang Chen, Section of Nephrology, Department of Internal Medicine, Linkou Chang Gung Memorial Hospital, Taoyuan, Taiwan; College of Medicine, Chang Gung University, Taoyuan, Taiwan.

Ming-Jui Hung, College of Medicine, Chang Gung University, Taoyuan, Taiwan; Section of Cardiology, Department of Internal Medicine, Keelung Chang Gung Memorial Hospital, Keelung, Taiwan.

Shu-Chen Liao, College of Medicine, Chang Gung University, Taoyuan, Taiwan; Department of Emergency Medicine, Keelung Chang Gung Memorial Hospital, Keelung, Taiwan.

Supplementary Material

aa-21-0108-File002_afab103

Associated Data

This section collects any data citations, data availability statements, or supplementary materials included in this article.

Supplementary Materials

aa-21-0108-File002_afab103

Articles from Age and Ageing are provided here courtesy of Oxford University Press

RESOURCES