Retrospective Study
Copyright ©The Author(s) 2023. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Infect Dis. Nov 22, 2023; 13(4): 37-48
Published online Nov 22, 2023. doi: 10.5495/wjcid.v13.i4.37
Analysis of clinical characteristics and risk factors between elderly patients with severe and nonsevere Omicron variant infection
Xiao-Qin Liu, Guan-Zhu Lu, Dong-Lin Yin, Yao-Yue Kang, Yuan-Yuan Zhou, Yu-Huan Wang, Jie Xu
Xiao-Qin Liu, Guan-Zhu Lu, Dong-Lin Yin, Yao-Yue Kang, Yuan-Yuan Zhou, Yu-Huan Wang, Jie Xu, Department of Infectious Disease, Shanghai Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011, China
Author contributions: Liu XQ designed the research study, analysed the data, and wrote the manuscript; Lu GZ, Yin DL, Kang YY, Zhou YY, and Wang YH collected and analysed the data; Xu J designed the research study and reviewed and revised the paper.
Institutional review board statement: This study was reviewed and approved by the Ethics Committee of the Ninth People’s Hospital Affiliated to Shanghai Jiao Tong University School of Medicine (Ethics Approval No.: SH9H-2022-T139-1).
Informed consent statement: As the study used anonymous and pre-existing data, the requirement for the informed consent from patients was waived.
Conflict-of-interest statement: We have no financial relationships to disclose.
Data sharing statement: No additional data are available.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Jie Xu, MD, Chief Physician, Department of Infectious Disease, Shanghai Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, No. 639 Manufacturing Bureau Road, Huangpu District, Shanghai 200011, China. xujie@shsmu.edu.cn
Received: October 3, 2023
Peer-review started: October 3, 2023
First decision: October 24, 2023
Revised: November 2, 2023
Accepted: November 13, 2023
Article in press: November 13, 2023
Published online: November 22, 2023
Processing time: 49 Days and 16 Hours
Abstract
BACKGROUND

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has led to millions of confirmed cases and deaths worldwide. Elderly patients are at high risk of developing and dying from COVID-19 due to advanced age, decreased immune function, intense inflammatory response, and comorbidities. Shanghai has experienced a wave of infection with Omicron, a new variant of SARS-CoV-2, since March 2022. There is a pressing need to identify clinical features and risk factors for disease progression among elderly patients with Omicron infection to provide solid evidence for clinical policy-makers, public health officials, researchers, and the general public.

AIM

To investigate clinical characteristic differences and risk factors between elderly patients with severe and nonsevere Omicron SARS-CoV-2 variant infection.

METHODS

A total of 328 elderly patients with COVID-19 admitted to the Ninth People’s Hospital Affiliated to Shanghai Jiao Tong University School of Medicine from April 2022 to June 2022 were enrolled and divided into a severe group (82 patients) and a nonsevere group (246 patients) according to the diagnosis and treatment protocol of COVID-19 (version 7). The clinical data and laboratory results of both groups were collected and compared. A chi-square test, t test, Mann-Whitney U test, hierarchical log-rank test, univariate and multivariate logistic regression, and hierarchical analyses were used to determine significant differences.

RESULTS

The severe group was older (84 vs 74 years, P < 0.001), included more males (57.3% vs 43.9%, P = 0.037), had a lower vaccination rate (P < 0.001), and had a higher proportion of comorbidities, including chronic respiratory disease (P = 0.001), cerebral infarction (P < 0.001), chronic kidney disease (P = 0.002), and neurodegenerative disease (P < 0.001), than the nonsevere group. In addition, severe disease patients had a higher inflammatory index (P < 0.001), greater need for symptomatic treatment (P < 0.001), longer hospital stay (P = 0.011), extended viral shedding time (P = 0.014), and higher mortality than nonsevere disease patients (P < 0.001). No difference was observed in the application of Paxlovid in the severe and nonsevere groups (P = 0.817). Oxygen saturation, cerebral infarction, and D-dimer were predictive factors for developing severe disease in patients with COVID-19, with D-dimer having an excellent role (area under the curve: 90.1%, 95%CI: 86.1-94.0%). In addition, D-dimer was a risk factor for developing severe COVID-19 according to multivariate stratified analysis.

CONCLUSION

The clinical course of severe COVID-19 is complex, with a higher need for symptomatic treatment. D-dimer is a suitable biomarker for identifying patients at risk for developing severe COVID-19.

Keywords: Coronavirus disease 2019; Omicron; Severe infection; Elderly patients; Clinical features; Risk factor

Core Tip: Since March 2022, the Omicron wave has affected Shanghai, China. Many elderly patients with severe and nonsevere Omicron severe acute respiratory syndrome coronavirus 2 variant infections have been admitted to our hospital. These patients have a precise diagnosis, complete examination, and clear treatment results. After China adjusts its coronavirus prevention and control policies in 2023, findings such as those in this article will no longer be available.