Evidence map›Paper›PMID 35451721›Full record

ArticleInfection2023

Clustering analysis reveals different profiles associating long-term post-COVID symptoms, COVID-19 symptoms at hospital admission and previous medical co-morbidities in previously hospitalized COVID-19 survivors.

César Fernández-de-Las-Peñas, José D Martín-Guerrero, Lidiane L Florencio, Esperanza Navarro-Pardo, Jorge Rodríguez-Jiménez, Juan Torres-Macho, Oscar J Pellicer-Valero

Open access · hybridAbstract read
In one paragraph

Article in Infection, 2023. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 34 papers, 2 of them syntheses that pooled it.

0numbers the graph read from it
0cells of the map it votes in
34citing papers in PubMed, 2 pooled it
6.7field-weighted citation impact, top 2% 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

34 citing papers in PubMed, 2 syntheses or guidelines pooled it, 57 citations in OpenAlex.

  1. Global prevalence of post-COVID-19 condition: a systematic review and meta-analysis of prospective evidence.Health promotion and chronic disease prevention in Canada : research, policy and practice · 2025
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  9. Post-COVID-19 physical and mental quality of life: a latent profile analysis and predictive factors.Quality of life research : an international journal of quality of life aspects of treatment, care and rehabilitation · 2026
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4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

7 authors at 3 institutions in 1 country.

César Fernández-de-Las-PeñasDepartment of Physical Therapy, Occupational Therapy, Physical Medicine and Rehabilitation, Facultad de Ciencias de la Salud, Universidad Rey Juan Carlos (URJC), Avenida de Atenas s/n, Alcorcón, 28922, Madrid, Spain. cesar.fernandez@urjc.es.ORCID http://orcid.org/0000-0003-3772-9690
José D Martín-GuerreroIntelligent Data Analysis Laboratory, Department of Electronic Engineering, ETSE (Engineering School), Universitat de València (UV), Valencia, Spain.
Lidiane L FlorencioDepartment of Physical Therapy, Occupational Therapy, Physical Medicine and Rehabilitation, Facultad de Ciencias de la Salud, Universidad Rey Juan Carlos (URJC), Avenida de Atenas s/n, Alcorcón, 28922, Madrid, Spain.
Esperanza Navarro-PardoDepartment of Developmental and Educational Psychology, Universitat de València (UV), Valencia, Spain.
Jorge Rodríguez-JiménezDepartment of Physical Therapy, Occupational Therapy, Physical Medicine and Rehabilitation, Facultad de Ciencias de la Salud, Universidad Rey Juan Carlos (URJC), Avenida de Atenas s/n, Alcorcón, 28922, Madrid, Spain.
Juan Torres-MachoDepartment of Medicine, Universidad Complutense de Madrid (UCM), Madrid, Spain.
Oscar J Pellicer-ValeroIntelligent Data Analysis Laboratory, Department of Electronic Engineering, ETSE (Engineering School), Universitat de València (UV), Valencia, Spain.
Universidad Rey Juan Carlos · ESUniversitat de València · ESUniversidad Complutense de Madrid · ES

Funding

Comunidad de Madrid LONG-COVID-EXP-CM
6 · The paper itself

Abstract

purposeTo identify subgroups of COVID-19 survivors exhibiting long-term post-COVID symptoms according to clinical/hospitalization data by using cluster analysis in order to foresee the illness progress and facilitate subsequent prognosis.

methodsAge, gender, height, weight, pre-existing medical comorbidities, Internal Care Unit (ICU) admission, days at hospital, and presence of COVID-19 symptoms at hospital admission were collected from hospital records in a sample of patients recovered from COVID-19 at five hospitals in Madrid (Spain). A predefined list of post-COVID symptoms was systematically assessed a mean of 8.4 months (SD 15.5) after hospital discharge. Anxiety/depressive levels and sleep quality were assessed with the Hospital Anxiety and Depression Scale and Pittsburgh Sleep Quality Index, respectively. Cluster analysis was used to identify groupings of COVID-19 patients without introducing any previous assumptions, yielding three different clusters associating post-COVID symptoms with acute COVID-19 symptoms at hospital admission.

resultsCluster 2 grouped subjects with lower prevalence of medical co-morbidities, lower number of COVID-19 symptoms at hospital admission, lower number of post-COVID symptoms, and almost no limitations with daily living activities when compared to the others. In contrast, individuals in cluster 0 and 1 exhibited higher number of pre-existing medical co-morbidities, higher number of COVID-19 symptoms at hospital admission, higher number of long-term post-COVID symptoms (particularly fatigue, dyspnea and pain), more limitations on daily living activities, higher anxiety and depressive levels, and worse sleep quality than those in cluster 2.

conclusionsThe identified subgrouping may reflect different mechanisms which should be considered in therapeutic interventions.

Indexed as

COVID-19Cluster AnalysisHospitalizationHospitalsHumansMorbidityPost-Acute COVID-19 SyndromeSurvivorsCOVID-19GroupsK-means clusteringLong COVIDPost-COVID

Identifiers

PMID35451721
PMCPMC9028890
OpenAlexW4224218963

What OpenQuestion holds

Textmetadata
LicenceCC BY
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.