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Meta-Analysis
. 2021 Mar;93(3):1449-1458.
doi: 10.1002/jmv.26424. Epub 2020 Aug 25.

Epidemiology of COVID-19: A systematic review and meta-analysis of clinical characteristics, risk factors, and outcomes

Jie Li  1   2 , Daniel Q Huang  3   4 , Biyao Zou  5 , Hongli Yang  2 , Wan Zi Hui  4 , Fajuan Rui  1 , Natasha Tang Sook Yee  4 , Chuanli Liu  1 , Sanjna Nilesh Nerurkar  4 , Justin Chua Ying Kai  4 , Margaret Li Peng Teng  3 , Xiaohe Li  6 , Hua Zeng  7 , John A Borghi  8 , Linda Henry  5 , Ramsey Cheung  5   9 , Mindie H Nguyen  5
Affiliations
Meta-Analysis

Epidemiology of COVID-19: A systematic review and meta-analysis of clinical characteristics, risk factors, and outcomes

Jie Li et al. J Med Virol. 2021 Mar.

Abstract

Coronavirus disease 2019 (COVID-19) has become a pandemic, but its reported characteristics and outcomes vary greatly amongst studies. We determined pooled estimates for clinical characteristics and outcomes in COVID-19 patients including subgroups by disease severity (based on World Health Organization Interim Guidance Report or Infectious Disease Society of America/American Thoracic Society criteria) and by country/region. We searched Pubmed, Embase, Scopus, Cochrane, Chinese Medical Journal, and preprint databases from 1 January 2020 to 6 April 2020. Studies of laboratory-confirmed COVID-19 patients with relevant data were included. Two reviewers independently performed study selection and data extraction. From 6007 articles, 212 studies from 11 countries/regions involving 281 461 individuals were analyzed. Overall, mean age was 46.7 years, 51.8% were male, 22.9% had severe disease, and mortality was 5.6%. Underlying immunosuppression, diabetes, and malignancy were most strongly associated with severe COVID-19 (coefficient = 53.9, 23.4, 23.4, respectively, all P < .0007), while older age, male gender, diabetes, and hypertension were also associated with higher mortality (coefficient = 0.05 per year, 5.1, 8.2, 6.99, respectively; P = .006-.0002). Gastrointestinal (nausea, vomiting, abdominal pain) and respiratory symptoms (shortness of breath, chest pain) were associated with severe COVID-19, while pneumonia and end-organ failure were associated with mortality. COVID-19 is associated with a severe disease course in about 23% and mortality in about 6% of infected persons. Individuals with comorbidities and clinical features associated with severity should be monitored closely, and preventive efforts should especially target those with diabetes, malignancy, and immunosuppression.

Keywords: COVID-19; clinical characteristics; mortality; risk factors; severe.

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Conflict of interest statement

Ramsey Cheung has received research support for Gilead Sciences. Mindie H. Nguyen has received research support from Gilead, BMS, and Janssen, and has served as an advisory board member or consultant for Dynavax, Gilead, Alnylam, BMS, Novartis, Spring Bank, and Janssen. Other authors have no disclosures.

Figures

Figure 1
Figure 1
Flow chart of systematic literature search and screening for studies of COVID‐19. COVID‐19, coronavirus disease 2019
Figure 2
Figure 2
A, Proportion of COVID‐19 patients requiring intensive care unit. B, Proportion of COVID‐19 patients requiring mechanical ventilation. C, Proportion of COVID‐19 patients with severe disease. D, COVID‐19 mortality. COVID‐19, coronavirus disease 2019
See this image and copyright information in PMC

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