Evidence map›Paper›PMID 32813298›Full record

Observational studyJournal of medical virology2021

Anemia is associated with severe illness in COVID-19: A retrospective cohort study.

Zheying Tao, Jing Xu, Wei Chen, Zhitao Yang, Xiaoman Xu, Ling Liu, Ruwu Chen, Jingyuan Xie, Mingyu Liu, Jingyi Wu and 2 more

Open access · bronzeAbstract readObservational Study
PubMed Full text at PMC Publisher
In one paragraph

Observational study in Journal of medical virology, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 98 papers, 5 of them syntheses that pooled it.

0numbers the graph read from it
0cells of the map it votes in
98citing papers in PubMed, 5 pooled it
3.4field-weighted citation impact, top 5% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

98 citing papers in PubMed, 5 syntheses or guidelines pooled it, 174 citations in OpenAlex.

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  10. Kidney involvement and anemia in COVID-19 infection.World journal of nephrology · 2025
    Review
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38 more citing papers are in PubMed but not listed here.

4 · The record

Corrections and comments

5 · Who and what money

Authors and funding

12 authors at 3 institutions in 1 country.

Zheying TaoDepartment of Critical Care Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
Jing XuDepartment of Critical Care Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
Wei ChenDepartment of Pulmonary and Critical Care Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
Zhitao YangEmergency Department, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
Xiaoman XuRenal Department, Wuhan Ninth Hospital, Wuhan, Hubei, China.
Ling LiuOphthalmologic Department of Renmin Hospital, Wuhan University, Wuhan, Hubei, China.
Ruwu ChenRenal Department, Wuhan Ninth Hospital, Wuhan, Hubei, China.
Jingyuan XieRenal Department of Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
Mingyu LiuRenal Department of Wuhan Ninth Hospital, Wuhan, Hubei, China.
Jingyi WuDepartment of Critical Care Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
Huiming WangRenal Department of Renmin Hospital, Wuhan University, Wuhan, Hubei, China.
Jialin LiuDepartment of Critical Care Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.ORCID 0000-0001-8763-7351
Shanghai Jiao Tong University · CNSoochow University · CNWuhan University · CN

Funding

Medical-engineering Cross Fundation of Shanghai Jiao Tong University"2019-nCoV research project" YG2020YQ30National Natural Science Foundation of China 8177010121National Natural Science Foundation of China 8197010190
6 · The paper itself

Abstract

Anemia commonly aggravates the severity of respiratory diseases, whereas thus far, few studies have elucidated the impact of anemia on coronavirus disease 2019 (COVID-19). The aim of this study was to evaluate the clinical characteristics of patients with anemia, and to further explore the relationship between anemia and the severity of COVID-19. In this single-center, retrospective, observational study, a total of 222 confirmed patients admitted to Wuhan Ninth Hospital from 1 December 2019 to 20 March 2020 were recruited, including 79 patients with anemia and 143 patients without anemia. Clinical characteristics, laboratory findings, disease progression and prognosis were collected and analyzed. Risk factors associated with the severe illness in COVID-19 were established by univariable and multivariable logistic regression models. In our cohort, compared to patients without anemia, patients with anemia were more likely to have one or more comorbidities and severe COVID-19 illness. More patients demonstrated elevated levels of C-reactive protein (CRP), procalcitonin (PCT) and creatinine in anemia group. Levels of erythrocyte sedimentation rate, D-dimer, myoglobin, T-pro brain natriuretic peptide (T-pro-BNP) and urea nitrogen in patients with anemia were significantly higher than those without. In addition, the proportion of patients with dyspnea, elevated CRP, and PCT was positively associated with the severity of anemia. The odd ratio of anemia related to the severe condition of COVID-19 was 3.47 (95% confidence interval [CI]: 1.02-11.75; P = .046) and 3.77 (95% CI: 1.33-10.71; P = .013) after adjustment for baseline date and laboratory indices, respectively. Anemia is an independent risk factor associated with the severe illness of COVID-19, and healthcare professionals should be more sensitive to the hemoglobin levels of COVID-19 patients on admission. Awareness of anemia as a risk factor for COVID-19 was of great significance.

Indexed as

AdultAgedAnemiaComorbidityCOVID-19C-Reactive ProteinDisease ProgressionHumansInflammationMiddle AgedProcalcitoninPrognosisRetrospective StudiesRisk FactorsSeverity of Illness IndexC-Reactive ProteinProcalcitoninanemiaCOVID-19hemoglobinrisk factorsevere illness

Identifiers

PMID32813298
PMCPMC7461220
OpenAlexW3049691358

What OpenQuestion holds

Textmetadata
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.